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gmx
02-20-2009, 05:52 AM
I changed my stock A4 tranny mount to a S4 mount but I'm still getting exactly this problem.

Every time I change gear I get a clunk, it feels like it's from the rear of the car.

Sometimes when I'm quickly on and off the throttle and the car doesn't respond quick enough the drivetrain will exhibit lots of shock and the car will buckle.

It happens in all gears, you can still feel it slightly when changing up to 4th.

3rd very little, but can still feel a bang.

1st to 2nd is a f'in nightmare, if I don't get the shift perfect the car bobs up and down or throws me forward. To get it smooth is almost luck and perfect clutch/gas application + high revs in 1st. Or just granny shift (and revs drop too low in traffic).

It's so much easier/smoother shifting at higher gears.


Could this be a bad clutch alignment? damaged/worn diff? Bad flywheel?

clutch is southbend stage 4 OFE SS + 16lbs flywheel with about 5k miles on it.

Dan[FN]6262
02-20-2009, 06:30 AM
its probably just the clutch and flywheel combo you have going on there.

thats a crazy clutch and the 16lb smf probably isnt helping either

get track mounts for the motor and tranny.

should help a little

AudiRacerS4
02-20-2009, 08:24 AM
Shank210;3399898']its probably just the clutch and flywheel combo you have going on there.

thats a crazy clutch and the 16lb smf probably isnt helping either

get track mounts for the motor and tranny.

should help a little

his problem doesnt sound like its a clutch or flywheel problem, people are running 9lb flywheels with no problem. Sounds like its your rear diff mount I had the same problem also check your rear subframe for cracks

njm23
02-20-2009, 08:33 AM
yeah definitely not from your clutch setup. I run that clutch with a 11lb flywheel, no issues

Do what he said and check your those 2 things out. ^^

andyrew
02-20-2009, 09:23 AM
Might also be your driveshaft carrier bearing. Or a combo of all of them. (Mine was a combo of motor mounts, trani mounts, driveshaft carrier bearing and rear drivetrain mounts)

mike-2ptzero
02-20-2009, 10:00 AM
Just sounds like the rear diff mount issue. This is why Stern came out with the power ring and why other companies came out with new rear diff mounts. It is going to happen more in the lower gears because there is more weight transfer to the rear in those gears and you see it more when shifting hard then if you are shifting slowly.

http://www.audizine.com/gallery/data/500/medium/2716Stern_RDM.jpg

tamadrumr88
02-20-2009, 10:22 AM
I did the snub mount, trans mounts, rear diff bushings and the one pictured above ("power ring" ?)... still no better (and by that I don't mean that the problem is still present, just to a lesser extent. I mean that the problem is still there and hasn't gotten any better although the car does vibrate considerably more at idle). There's also no purple fluid leaking from the motor mounts so I don't think they're shot either.

mike-2ptzero
02-20-2009, 11:01 AM
I wonder if how much the car has been lowered makes a difference.

andyrew
02-20-2009, 02:40 PM
Driveshaft carrier bearing?

AudiRacerS4
02-20-2009, 03:55 PM
check to see if your rear subframe is cracked, my friend was having the same problem with his S4 and the rear subframe was cracked in two places

gmx
02-20-2009, 05:41 PM
ok, just got under the car and could not see any cracks around the subframe.

I fiddled with the exhaust hangers and with enough movement it was hitting the chassis (stock exhaust).

I checked out the diff mounts and could not make the budge. The bushes did look worn though.
Last thing to check is the snub.

Sounds dumb, but I can't locate the diff carrier bearing?

Right now I'm trying to adjust the height of the car (lift it .5")

mike-2ptzero
02-20-2009, 05:49 PM
Did you look just above the rear diff where the driveshaft meets it to see if the diff is hitting the frame above it? Because the rear diff mount isn't really going to move much when you push on it, it moves when the rear of the car squats from weight transfer and when the rear drive shaft pushes the diff up.

andyrew
02-20-2009, 08:49 PM
Diff carrier bearing.

Remove heat shields, its in the center of the driveshaft (Driveshaft = 2 pieces)

mike-2ptzero
02-20-2009, 09:39 PM
But if it was that bearing wouldn't there be issues all the time seeing that the bearing doesn't just come into play when he is shifting?

Squarrl
02-20-2009, 10:12 PM
see if your axles have a lot of play my inner cv made that noise when it was broken...

andyrew
02-21-2009, 12:19 AM
But if it was that bearing wouldn't there be issues all the time seeing that the bearing doesn't just come into play when he is shifting?

Nope, mine just clunked during shifting. Changed it and it was much better.

gmx
02-26-2009, 11:46 PM
Looked into getting snub and some diff mounts.

I probably should start a new thread but I"ll try here first.
I tried the tech talk section a long time ago but no news.

Problem:
I get a loud sqeel when putting load on the clutch.

Ie:
Hill starts and slipping it out slowly. It almost sounds like tyres chirping but definitely isn't (new ones anyway).
It also happens shifting through 1st to 3rd. Occasionally it will do it on 4th (very faint) and rarely 5th. If the downshift isn't perfectly matched, same story.

I had a VAG specialist look at it and he says it's coming from the flywheel area (I told him not to bring the trans down yet) and doesn't believe it's anything that will suddenly fail.


The only post I could find showed Clint had a similar issue on one of his boxes but never found what it was due to swapping parts etc.
I reckon it's the pressure plate as the squeal happens at a constant pedal position/engagement position (near the top/end of engagement).


This use to only happen shifting at higher rpm (about 5k~) from 1st to 2nd and to 3rd. But now it will do it 1st to 2nd on a typical shift (around 3.5k rpm), unless I granny it so revs are around 1.25k max when engaging 2nd.

Bendy
06-10-2009, 06:53 PM
I have the same problem during shifting. I have filled the rear diff mounts with urethane ($35 + labor :) ) replaced the driveshaft and carrier bearing, and installed a Greedspeed snub (stock metal bracket that allows movement still there), and 034 transmission mounts (street density) and it still clunks terrible if I let out the clutch quickly. I've learned to drive it by always letting out the clutch slowly to avoid it, but I want to fix it. Did you ever find a solution? I ordered some OEM engine mounts today to hopefully fix it.

FYI, I do have a stage 3 OFE Southbend clutch with the Fidanza ~16lb flywheel too. That flywheel makes some nasty racket at about 1500rpm let me tell ya...

gmx
06-11-2009, 02:44 AM
still same problem. It's at the point where I can't let anyone else drive it and every passenger wants to kill me for driving like I just started stick.

Check out this thread
http://audizine.com/forum/showthread.php?t=167999

I can't emphasize this enough. 1-2 shift is a FUCKING nightmare. If I don't time it perfect (also dependent on the gradient of the road), the car bogs, there is no response from accelerating, then all of a sudden it picks up again.
I have to let out the clutch soooooo slow to even get it remotely smooth. Even then a noticable clunk/bang like the 3-4-5. By that point revs are so low.

1-2 is almost impossible to get smoothly done.
3-4-5 give a noticable bang sound.

I've ordered some rear diff mounts and a snub and I"ll see. But by going through those threads I doubt it's the mounts. I was thinking driveshaft also.

I just changed the gearbox and rear diff fluids changed. Still same.

Another thing to point out. Would JHM solid linkages cause such a feeling? I have no idea in this part of the car and I'm just going to drop it off to my specialist for diagnosis after I do the mounts at least.

So far I'm thinking:
JHM linkages
Driveshaft
driveshaft center bearing

Bendy
06-11-2009, 03:23 AM
I have the JHM solid shift linkage and shift stabilizer as well. Love the feel. I highly doubt this could be the cause. I ordered some motor mounts yesterday. Should be here early next week. I'm going to perform a thorough inspection of the car this weekend. I've wanted to have someone else drive it with the hood open so I can see if/how much the engine is jumping around when I do it. The other thing I wonder is if the urethane has worked itself out of the rear diff mounts. I believe I did a pretty good job with it and they were rock solid when I reinstalled them, but I will inspect this as well.

I have learned to drive the car smoothly, but its taken a LONG time. Gotta let that clutch out really slow every shift. If you let it out quickly without the exact correct application of the throttle, it feels like the drivetrain is going to bust the bolts that hold it in and fall on the ground. There is a back-and-forth wave of clunking that hits 3-4 times when you do it. It's hard to believe it's that bad with my solid diff mounts, 034 street density trans mounts, Greedspeed snub, and rebuilt driveshaft with new carrier bearing. I WILL figure this out.

Edit: I just noticed you have 034 engine mounts in your sig. Replacing mine does not look very promising then.

mike-2ptzero
06-11-2009, 07:56 AM
still same problem. It's at the point where I can't let anyone else drive it and every passenger wants to kill me for driving like I just started stick.

Check out this thread
http://audizine.com/forum/showthread.php?t=167999

I can't emphasize this enough. 1-2 shift is a FUCKING nightmare. If I don't time it perfect (also dependent on the gradient of the road), the car bogs, there is no response from accelerating, then all of a sudden it picks up again.
I have to let out the clutch soooooo slow to even get it remotely smooth. Even then a noticable clunk/bang like the 3-4-5. By that point revs are so low.

1-2 is almost impossible to get smoothly done.
3-4-5 give a noticable bang sound.

I've ordered some rear diff mounts and a snub and I"ll see. But by going through those threads I doubt it's the mounts. I was thinking driveshaft also.

I just changed the gearbox and rear diff fluids changed. Still same.

Another thing to point out. Would JHM solid linkages cause such a feeling? I have no idea in this part of the car and I'm just going to drop it off to my specialist for diagnosis after I do the mounts at least.

So far I'm thinking:
JHM linkages
Driveshaft
driveshaft center bearing

The JHM linkage wouldn't be the cause of the problem. It just makes the actual shifting gears feel more solid.

Sounds like it could be a driveshaft issue, you might want to see if the driveshaft has too much play where it connects to the transmission and the diff because the actual driveshaft is connected to the flanges with rubber.

Bendy
06-11-2009, 08:04 AM
I put the new driveshaft in last year, and I remember it making a lot of difference in shifting, but I still remember having some level of this issue left. By that point, I had already adapted my driving style to avoid the issue as much as possible, and with the new driveshaft, I think I was finally able to drive it without clunking, albeit doing do very carefully.

I will check EVERYTHING under there, regardless if I have previously fixed it. I'm hoping after all these problems that I haven't damaged any of the differentials, causing massive play in them. Is that possible?

mike-2ptzero
06-11-2009, 09:23 AM
I put the new driveshaft in last year, and I remember it making a lot of difference in shifting, but I still remember having some level of this issue left. By that point, I had already adapted my driving style to avoid the issue as much as possible, and with the new driveshaft, I think I was finally able to drive it without clunking, albeit doing do very carefully.

I will check EVERYTHING under there, regardless if I have previously fixed it. I'm hoping after all these problems that I haven't damaged any of the differentials, causing massive play in them. Is that possible?

Could be a damaged diff. I run all solid motor/transmission mounts, JHM linkage/bushing upgrades, Stern Power Ring and rear diff bushing upgrades and I dont have any of these issues.

silver_a4
06-11-2009, 01:20 PM
I got the same issue, its even worse when the a/c is on, it clunks bad even up to 5th gear sometimes. On some days, while the engine is cold, it doesn't clunk at all. An audi tech put my car on the lift and inspected it and found no problems except for my exhaust clamps were broken. I recently got a new snub mount, not sure what else i need to change

Bendy
06-12-2009, 03:51 AM
I did some checking last night. I realized I could clunk it really good just by being stationary, idling, and popping the clutch just enough to jerk the drivetrain, but not move the car or kill the engine. The engine moves A LOT. I mean, it jumps like you yelled "CLEAR!" and used a defibrilator on it. I also watched the rear diff while I did this. It does not budge. The 94 shore urethane filled stock diff mounts are intact and doing their job. The movement is all in the front. And this with a Greedspeed snub (not sure how much this really helps since the stock metal surround it sits in is larger than the mount - I'm sure an 034 Motorsports one with the fitting surround would be better) and 034 street density transmission mounts, but stock 118k motor mounts. The new OEM replacement mounts ($80 for two from www.autohausaz.com - I cheaped out over $180 for two 034 ones this time) are scheduled to be delivered on Wednesday.

gmx
06-12-2009, 07:23 AM
My engine doesn't move when revved in N. (opening the TB by hand).
I have 034 street mounts there.
I read a post here once that a guy grabbed his intake manifold and was able to move his engine. Mine won't budge, I truly think it's locked down.

But I guess when in gear it depends much more on the snub. I haven't inspected the snub in there, but I wouldn't be surprised if I don't even have one... that's how bad it is.

mike-2ptzero
06-12-2009, 07:47 AM
I did some checking last night. I realized I could clunk it really good just by being stationary, idling, and popping the clutch just enough to jerk the drivetrain, but not move the car or kill the engine. The engine moves A LOT. I mean, it jumps like you yelled "CLEAR!" and used a defibrilator on it. I also watched the rear diff while I did this. It does not budge. The 94 shore urethane filled stock diff mounts are intact and doing their job. The movement is all in the front. And this with a Greedspeed snub (not sure how much this really helps since the stock metal surround it sits in is larger than the mount - I'm sure an 034 Motorsports one with the fitting surround would be better) and 034 street density transmission mounts, but stock 118k motor mounts. The new OEM replacement mounts ($80 for two from www.autohausaz.com - I cheaped out over $180 for two 034 ones this time) are scheduled to be delivered on Wednesday.

The new OEM motor mounts might help a little since your stock ones are most likely dead, but the engine is still going to move since the stock ones really dont hold the engine very still. Making everything else on the driveline stiff doesn't do much good if you allow the 1 thing that actually twists to move around. The snub mounts job is just to keep the engine in a straight line with the rest of the driveline, when the engine makes tq it rotates and its the engine mounts job to reduce how much it moves as it produces tq.

Bendy
06-12-2009, 07:54 AM
I actually tried to trade the car in on Wednesday and the dealer would not accept the car with that going on during shifts. I completely avoid it with my driving style, but "normal" manual driving techniques of not being super-careful with the clutch make the clunk happen. I'm trying to get it acceptable to him so I can complete the deal. I'd rather spend $80 versus $180 for a car I'm hopefully not going to own next week. With improved everywhere else and stock there, in theory the drivetrain should be held tighter than it was when new.

B5turbo
06-12-2009, 07:55 AM
alot of replies... i have the same exactttttttttt problem!

mechanic said it could be the bushings in the tranny.. i think hes wrong

mike-2ptzero
06-12-2009, 09:02 AM
I actually tried to trade the car in on Wednesday and the dealer would not accept the car with that going on during shifts. I completely avoid it with my driving style, but "normal" manual driving techniques of not being super-careful with the clutch make the clunk happen. I'm trying to get it acceptable to him so I can complete the deal. I'd rather spend $80 versus $180 for a car I'm hopefully not going to own next week. With improved everywhere else and stock there, in theory the drivetrain should be held tighter than it was when new.

Well if your trying to get rid of the car then yes that is perfectly fine.

andyrew
06-12-2009, 09:19 AM
For all you with trani clunk issues. I want to say I have narrowed mine down (did this a while ago).

I have replaced and reinforced every single drivetrain component and every single mount. (Urithaned half of them..) My issue is the trani itself. My trani is causing my clunking and its very obvious that thats where the noise is coming from.


Just thought I'd make you all aware of the possibility..

mike-2ptzero
06-12-2009, 09:37 AM
For all you with trani clunk issues. I want to say I have narrowed mine down (did this a while ago).

I have replaced and reinforced every single drivetrain component and every single mount. (Urithaned half of them..) My issue is the trani itself. My trani is causing my clunking and its very obvious that thats where the noise is coming from.


Just thought I'd make you all aware of the possibility..


Did you ever swap out the trans with the one you picked up a while ago?

andyrew
06-12-2009, 11:16 AM
Heh. no...

Im running this one till its GONE. Which just might be a while... But I have a lot of autox's on the schedule this season.. so who knows.
I will open up the old one when I do switch it out though.

gmx
06-12-2009, 05:57 PM
what would be causing this in the trans?
Syncros?

Wizard-of-OD
06-13-2009, 10:28 AM
Driveshaft carrier bearing?
That was my thinking as well.
Hit me up on msn

andyrew
06-13-2009, 11:33 AM
what would be causing this in the trans?
Syncros?

Im not a trans expert, but I'll say bearings probably. If they develop slack then they would cause a large internal movement between power on and power off.

Thats my guess for the problem. Oh and my sycro's are going bad as well, I know that (first gear is gone..)

Bendy
06-17-2009, 05:15 PM
Got my new OEM motor mounts yesterday. Installed them tonight. Guess what? No change at all. $80 and two hours of work for nothing.

I don't know what else to do besides swap my spare tranny back in. My current tranny has what I believe is a bad input shaft bearing. You can hear a ticking with the car running, trans in neutral, and clutch out. As soon as you push the clutch in, the ticking goes away. However, I can't imagine what happens between shifts happening in just the transmission. The engine definitely moves a lot, but any engine would with the amount of shock I put in the driveline when I'm testing it. It's the jerking/bouncing around of the engine that is the most disconcerting.

A transmission swap is such a huge and time consuming project that I'd hate to do another one just because of the remote possibility that this is the issue.

Let's go back to the lightened and single-mass flywheel. The dual-mass stocker will dampen shock to the driveline. Could the single mass be the main culprit here?

Bendy
06-18-2009, 09:22 AM
Just read another thread on AudiWorld where a guy with a 2.8 like me has the same issues, replaced all the drivetrain mounts, and also has a dual-mass stock flywheel and still has the clunk, so that's out.

However, after reading a bit more, I'm thinking subframe mounts or the subframe itself could be the culprit. I've read a few threads where subframe bolts were loose or missing, or the subframe itself was cracked due to age/corrosion/crappy factory construction. This is not something I have considered. I was getting very frustrated thinking I've covered all the bases with mounting the drivetrain to the car - what else could there be? I forgot there is not just "drivetrain connected to car" - there's a subframe there in the middle!

When I go home this afternoon, I am going thoroughly inspect the front subframe.

mike-2ptzero
06-18-2009, 09:29 AM
Got my new OEM motor mounts yesterday. Installed them tonight. Guess what? No change at all. $80 and two hours of work for nothing.

I don't know what else to do besides swap my spare tranny back in. My current tranny has what I believe is a bad input shaft bearing. You can hear a ticking with the car running, trans in neutral, and clutch out. As soon as you push the clutch in, the ticking goes away. However, I can't imagine what happens between shifts happening in just the transmission. The engine definitely moves a lot, but any engine would with the amount of shock I put in the driveline when I'm testing it. It's the jerking/bouncing around of the engine that is the most disconcerting.

A transmission swap is such a huge and time consuming project that I'd hate to do another one just because of the remote possibility that this is the issue.

Let's go back to the lightened and single-mass flywheel. The dual-mass stocker will dampen shock to the driveline. Could the single mass be the main culprit here?


Not unless your running a unsprung disk. The sprung disk works just like the dual mass flywheel. I have been using a lwfw in my A4 for about 7+ years and have never had an issue. Even when I was running a unsprung disk with a 12 lbs flywheel I never had a clunk issue when engaging the clutch.


You might want to check your exhaust hanger bolts that also go thru the rear diff mount arm. If that is loose you will hear a clunk.

Bendy
06-18-2009, 09:37 AM
It is a Southbend "Stage 3" OFE clutch with a sprung hub. It is pretty smooth. Chatters very occasionally, but I think most OEM clutches can chatter every once in a while too.

I really don't like my lightened flywheel. It make a terrible racket at low RPM and I have tons of heavy vibration along with it, especially in higher gears. With the stock setup, I could full throttle accelerate at 800rpm and the car would be smooth as can be. Removing that 13 pounds of weight lets those vibrations that would otherwise be dampened out through the drivetrain. I'd really rather have a stock one. Anyone want to trade? :)

I do really like the clutch though. I highly recommend it.

mike-2ptzero
06-18-2009, 09:51 AM
It is a Southbend "Stage 3" OFE clutch with a sprung hub. It is pretty smooth. Chatters very occasionally, but I think most OEM clutches can chatter every once in a while too.

I really don't like my lightened flywheel. It make a terrible racket at low RPM and I have tons of heavy vibration along with it, especially in higher gears. With the stock setup, I could full throttle accelerate at 800rpm and the car would be smooth as can be. Removing that 13 pounds of weight lets those vibrations that would otherwise be dampened out through the drivetrain. I'd really rather have a stock one. Anyone want to trade? :)

I do really like the clutch though. I highly recommend it.

What flywheel did you go with? Because I always suggest the steel flywheels for people that daily drive the cars. So the 15,17 and 20 lbs flywheels are what most people should use on the street. For nothing but street driving the 20 lbs flywheel from SB is a great choice. It only drops off about 6 lbs and has no gear rattle at idle.

Bendy
06-18-2009, 09:57 AM
It is a 15lb one. I didn't realize there were different options of weights from Fidanza. SouthBend had one sitting on a shelf unbeknownst to them. They recoemmended getting a new one when they had to take off 25 thousandths from my stocker and Andy thought it was too close to being out of spec to use. I visited their shop since its only about a 2 hour drive from my town.

What is gear rattle? Is that what I'm experiencing in neutral at a stop? Or is that the low rpm terrible noise I get?

B5A4Kevin
06-18-2009, 10:12 AM
i figured it out for you. whoever installed your flywheel did it wrong, and now your crankshaft is backwards. this is causing the pressure plate to rub on your timing belt.....





j/k. sorry im not much help to you, but ive never seen this issue. i can, however, understand how frustrating it must be. best of luck to you and hope you get it figured out soon. peace.

mike-2ptzero
06-18-2009, 11:28 AM
It is a 15lb one. I didn't realize there were different options of weights from Fidanza. SouthBend had one sitting on a shelf unbeknownst to them. They recoemmended getting a new one when they had to take off 25 thousandths from my stocker and Andy thought it was too close to being out of spec to use. I visited their shop since its only about a 2 hour drive from my town.

What is gear rattle? Is that what I'm experiencing in neutral at a stop? Or is that the low rpm terrible noise I get?

Its not from Fidanza. There are just a few weight options from different companies when it comes to the Billet steel flywheels.

Spec = 15 lbs

South Bend = 20 and I was able to talk Andy into making a 17 lbs cut down version

Clutch Masters = 14 lbs

All of them can be used with any of the clutch kits designed for a stock flywheel since the specs are all basically the same.

Gear rattle is what you hear when you are in neutral, at idle and without pushing the clutch pedal in. The lighter or less dense the material the flywheel is made with the more rattle you will hear.

Bendy
06-18-2009, 11:42 AM
I finally have a good description and NAME for this noise! All I could garnish from forums was that "lightened flywheels are just noisy on Audis" and I left it at that. I also made a special trip to South Bend since I was so concerned about the noise (the low rpm noise, not necessarily the idle noise) and Andy just said the same thing after driving it "Its just the flywheel" without being able to get any more specific. As far as the gear rattle, they put it up on the lift and we listened to it in detail and Andy was sure it was an input shaft bearing, even though the sound was comign from the rear of the tranny.

Andy said it was a Fidanza that I bought, althought I don't remember seeing any markings on the box or flywheel itself. He weighed it at the shop and it was about 15lbs.

So is the low rpm "zh" racket I get also considered "gear rattle"? Or is that something else?

Sorry to get off topic here a bit, guys...

Bendy
06-18-2009, 12:43 PM
The rear subframe mounts in the front move pretty easy with a prybar, but not under jerking the drivetrain. I had the front of the car on jackstands with the e-brake on and had my wife jerk the clutch at idle (no, I wasn't directly under the car) and the stuff that moved the most was the engine/tranny and exhaust. The (034 street density) transmission mounts compress downward and bounce. The engine jumps up. The diff does not budge! I can bounce my engine around by hand in the engine bay, so the engine and tranny are still pretty loose. I think the engine is just hitting something in the engine bay when it bounces. Maybe I'll stuff a correctly sized piece of wood between the top of the snub mount and the housing it sits in and see how well that prevents it. ???

Bendy
06-19-2009, 07:36 AM
I stuck a nut in between the snub mount and its cage and I think I noticed a slight difference, but the tranny still compresses its mounts even though the engine moves less., still causing quite a bit of ruckus. This tells me I need a DTS. Here is my current plan of attack:

Part 1:

AWE DTS?

http://www.awe-tuning.com/pages/shared/part_detail.cfm?PMaI=1&PMoI=1&PEI=3&PP=a4_28_drivetrain.cfm&PPT=Drivetrain&IL=AWEDTS

There's no way I'm paying $350 much for something so simple. If you look at the link below, you can see what the pretty piece looks like that attaches to the tranny and what is there stock that just ties the two sides of the car together for chassis strengthening:

http://www.awe-tuning.com/pages/gallery/awe_dts/index.cfm

There is a mount that connects between the DTS and the transmission that you can't get separately UNLESS you get the upgraded one from JHMotorsports:

http://www.jhmotorsports.com/shop/catalog/product_info.php?products_id=54

I will buy this $40 mount by itself and then devise a way to connect this transmission-attached mount to the existing crossbar. If you look closely at the second link above, you may notice that the AWE bar is positioned directly across from the bolt heads whereas the stock piece is just a bit above the bolt hole. I think it would be as easy as getting a small metal plate, drilling holes in it to attach to this $40 mount and then drill holes through the existing bar to connect to the plate in order to bridge that gap. It probably won't be quite as strong as the $350 showpiece, but I think it will do the job. If the stock brace proves to weak to support this, I can source metal plates and bars for a pittance compared to the showpiece.

Part 2:

I already have the polyurethane snub mount, but the stock cage allows for a lot of movement. As opposed to trying to jury rig something to keep the snub mount in place, I'd rather just buy the fitted cage for $45. Not that much money as compared to all the engineering I'd have to do.

http://www.jhmotorsports.com/shop/catalog/product_info.php?products_id=55{40}47{41}61

You can specify "I already have the poly snub mount" and just get the cage. I'll also spring for the $8 bolt kit.

So that would be $93 plus shipping. Probably won't be able to spring for this purchase for another week or two, but I'll post when I get it done.

mike-2ptzero
06-19-2009, 07:53 AM
What transmission mounts are you running now?

I still run a stock snub cage and no DTS and my transmission/motor dont move an inch, but then thats because I run solid mounts on both the engine and transmission.

Bendy
06-19-2009, 08:06 AM
034 street density trans mounts with stock (good condition) motor mounts. The move quite a bit when you torque the drivetrain. I was very surprised when I watched. Knowing I was selling the car soon, I didn't want to go with the race density thinking this might cause undue NVH for prospective owners.

I can't believe the drivetrain would be this loose and clanging around from the factory. The 96 Prizm I am trying to trade for with 150k miles doesn't make any noise or adverse thumps no matter what you do.

mike-2ptzero
06-19-2009, 08:12 AM
You could try changing the passenger side transmission mount to a track since thats the direction the transmission is going to twist when the engine makes tq. If it doesn't help it shouldn't be hard to sell that mount.

Bendy
06-19-2009, 08:40 AM
Interesting idea. When I watched them compress under the car, I was watching the driver's side one in more detail and it moved quite a bit - at least half an inch of compression? I would replace both if I were to try this. But my homemade DTS idea is still cheaper than one $60 034 mount and I think it will do a lot more.

gmx
06-20-2009, 12:30 AM
Someone else touched on not smooth shifting in their S4.

And mentioned the stock clutch pedal switch... I have nfi idea what that is. What do you guys reckon?

.Mad Hatter.
06-20-2009, 05:46 AM
You might want to check your exhaust hanger bolts that also go thru the rear diff mount arm. If that is loose you will hear a clunk.

Mike I could kiss you!

I got a clunk after getting a custom exhaust put on; I assumed he forgot to weld a hanger on...

mike-2ptzero
06-20-2009, 08:16 AM
Someone else touched on not smooth shifting in their S4.

And mentioned the stock clutch pedal switch... I have nfi idea what that is. What do you guys reckon?

Check your engine/transmission mount brackets.

AudiA4_20T
06-20-2009, 09:56 AM
Problem:
I get a loud sqeel when putting load on the clutch.

Ie:
Hill starts and slipping it out slowly. It almost sounds like tyres chirping but definitely isn't (new ones anyway).
It also happens shifting through 1st to 3rd. Occasionally it will do it on 4th (very faint) and rarely 5th. If the downshift isn't perfectly matched, same story.

I had a VAG specialist look at it and he says it's coming from the flywheel area (I told him not to bring the trans down yet) and doesn't believe it's anything that will suddenly fail.


The only post I could find showed Clint had a similar issue on one of his boxes but never found what it was due to swapping parts etc.
I reckon it's the pressure plate as the squeal happens at a constant pedal position/engagement position (near the top/end of engagement).


This use to only happen shifting at higher rpm (about 5k~) from 1st to 2nd and to 3rd. But now it will do it 1st to 2nd on a typical shift (around 3.5k rpm), unless I granny it so revs are around 1.25k max when engaging 2nd.

I did a clutch for someone awhile ago and he said all of the sudden his is doing this too... I am going to pull the trans out soon and see what I can find

Btw, these were all on Southbend clutches. Could be install or could be the clutch idk

Bendy
06-22-2009, 07:20 PM
Made my homemade DTS tonight. It all started when I came across this old bracket in my shed that I thought could work. Well, it did.

http://lh5.ggpht.com/_8UKlDnUxFp8/SkAp1T6zMNI/AAAAAAAAB-g/-rgANomoobo/s800/100_1173S.JPG

It went back just far enough to be right of the center of the original crossbar. I knew that crossbar wasn't going to support the forces that were going to be placed on it, so I got my dad to come over to help engineer this thing. My heavy machinery maintenace dude neighbor was mowing his lawn and my dad said I should ask him if he had any scrap metal around that could take the place of that little crossbar, and lo and behold he had the perfect piece of 1/4 inch thick 2 inch wide steel. He used his torch to flatten it out and cut it to size. Drilled a couple holes and it was the basis for the reinforcement.

http://lh5.ggpht.com/_8UKlDnUxFp8/SkAp0yr10uI/AAAAAAAAB-U/sYSFvYwciM8/s800/100_1170S.JPG

http://lh5.ggpht.com/_8UKlDnUxFp8/SkAp09_1MVI/AAAAAAAAB-Y/dHu4LX3G1l8/s800/100_1171S.JPG

We decided to get a u-bolt to go through the hole in the bracket and hold on to the bar.

http://lh3.ggpht.com/_8UKlDnUxFp8/SkAp1IeyMnI/AAAAAAAAB-c/UQ9H-aTfWps/s800/100_1172S.JPG

For lack of better materials, we used a piece of wood and some rubber matting for lining tool box drawers to go between the crossbar and the bottom of the bracket.

http://lh3.ggpht.com/_8UKlDnUxFp8/SkAp1ar9xNI/AAAAAAAAB-k/guUXnvwAcTY/s800/100_1174S.JPG

It's a work in progress. I know we need a stronger U bolt and different material between the bar and bracket.

First impressions - definitely a difference. Definitely still not acceptable. Taking off in first gear slowly now has NO drivetrain slack. Shifting carelessly still scares the people walking on the sidewalk nearby. I'm sure they are thinking "What is wrong with that car?"

Next is improving this setup. Then getting a solid cage for the snub.

mike-2ptzero
06-22-2009, 09:11 PM
You seem to be throwing band aids at a much larger issue.

somebody5788
06-22-2009, 09:14 PM
I could never put a clamp like that under my car ... I'd rub on everything.. I am barely lower then stock sport.

.Mad Hatter.
06-22-2009, 10:31 PM
for the record, the stern rear diff. mount bushings solved my rear clunk

Bendy
06-23-2009, 03:11 AM
Driving to work this morning, I don't think I gave it enough credit. As opposed to all kinds of ka-klunk-ka-klunk during careless shifting, I now just have a single, solid "thud" somewhere under my right elbow. It could be some play in what I made, or possibly something to do with the driveshaft. This DEFINITELY helped. The car actually feels like it "stays together in one piece" when slipping the clutch away from a stop.

I'll go back and read your previous posts, mike-2ptzero, but I'm not sure what you are referring to. The engine mount brackets are attached to the subframe and they are very tight as I just replaced the engine mounts last week and had these bolts out and back in. I guess I could check the transmission mount brackets, but I've had this tranny off 3 times, and thus these brackets off and on three times, and this problem has not changed, at least since the 1st time when I put in the clutch and flywheel.

We cut the u bolt shorter than how it came. We wanted to leave enough threads to double-nut it. We left it a little long just in case with the option to make them shorter. We will be getting a beefier U bolt anyways, so this one will probably not be further modified. The finished product will have the U bolt be as short as possible.

Getting close!

mike-2ptzero
06-23-2009, 08:32 AM
I would double check the transmission bracket bolts that go into the transmission since they tend to be left loose while putting the transmission back in so it is slightly easier to line up the bracket with the mounts, then go back and tighten all of the bracket bolts at the transmission after the mounts. The other bolts I was talking about is the ones at the other end of the drive shaft at the rear diff, there are 2 bolts that bolt the rear diff mount bracket to the actual car and those 2 bolts also go thru one of the exhaust hangers. But if you hear the sound right next to you while sitting in the driverseat it is going to be something right at the back of the transmission, maybe something to do with the rear output shaft or the driveshaft were it bolts the rear output shaft.

Bendy
06-23-2009, 09:47 AM
I know all these bolts you speak of and will check all these things when I get under there next - hopefully tonight. My dad emailed and said he had found all kinds of rubber to reply my wood block under there.

Bendy
06-24-2009, 07:09 PM
PROBLEM SOLVED!!!

First, we finalized our work from two days ago by replacing the wood and drawer liner with industrial rubber. We also replaced the skinny U bolt with a beefy one. The Homemade DTS was made from things I, my neighbor, and my dad had lying around and the cost of a $3 exhaust U bolt from Autozone. A LITTLE bit cheaper than an AWE aircraft aluminum version!

http://lh3.ggpht.com/_8UKlDnUxFp8/SkLJGgaSlDI/AAAAAAAAB_A/HGi5Iv_gOOM/s800/100_1186.JPG

http://lh3.ggpht.com/_8UKlDnUxFp8/SkLJHOv8SZI/AAAAAAAAB_E/q1GQnR41tsY/s800/100_1188.JPG

http://lh3.ggpht.com/_8UKlDnUxFp8/SkLJHlm6UjI/AAAAAAAAB_I/CH5L5xrvuio/s800/100_1189.JPG

Drove it around, no change from yesterday. Next I looked at the exhaust from previous recommendation on this thread. Aha! It does bang the rear subframe! I was REALLY close to it:

http://lh3.ggpht.com/_8UKlDnUxFp8/SkLJH8xl07I/AAAAAAAAB_M/9XaBKNEBHhQ/s800/100_1192.JPG

I found there's a reason for that also previous mentioned by those more experienced than I in this thread - the exhaust hanger had rusted off long ago and I didn't think anything of it!

http://lh3.ggpht.com/_8UKlDnUxFp8/SkLJIe_H4XI/AAAAAAAAB_Q/AChahrVmU-w/s800/100_1194.JPG

Pulled that rubber hanger back down and a little wire took care of that.

http://lh5.ggpht.com/_8UKlDnUxFp8/SkLJI-QDebI/AAAAAAAAB_U/btgMfo0gKQk/s800/100_1195.JPG

http://lh3.ggpht.com/_8UKlDnUxFp8/SkLJJBKMeNI/AAAAAAAAB_Y/tnX-YzFBD7A/s800/100_1196.JPG

Still had the thud. Got the car up on all fours and took a look under. Before when I just had the front end off the ground, the diff didn't budge. Well it did now! The diff moved separate from the rear support plate like the bolts were broken!!! Well, actually the bolts were not broken. ALL THREE WERE LOOSE! There were all the way in their recessed holes, but could be loosened by hand. Either I didn't tighten them when I had this support plate out to fill the bushings with urethane, or these are some of the bolts on the car that really, truly need loctite.

http://lh6.ggpht.com/_8UKlDnUxFp8/SkLNE8ZQJuI/AAAAAAAAB_0/Z97r12KUN_g/s800/100_1194loose.JPG

After tightening these three bolts, the car is PERFECT! No clunks at all during driving! Yeehaw! Thanks for everyone's suggestions!

Never give up! Never surrender to your car!!! :)

.Mad Hatter.
06-24-2009, 10:18 PM
that may be part of what solved my issue, i replaced the rear diff. bushings and of course tightened those bolts afterward.

gmx
06-27-2009, 07:10 AM
So is the low rpm "zh" racket I get also considered "gear rattle"? Or is that something else?

Sorry to get off topic here a bit, guys...

I believe it's engine vibration just not dampened enough.
I think running such low rpms and getting this racket is referred to as lugging the engine.

It's so damn cold here otherwise I'd jack up the car again (not that anything would be resolved).


I did a clutch for someone awhile ago and he said all of the sudden his is doing this too... I am going to pull the trans out soon and see what I can find

Btw, these were all on Southbend clutches. Could be install or could be the clutch idk

Not surprised, I think it's a rivet coming loose. And the support from Southbend has been a little disappointing
Question, if it is... is my flywheel screwed?
I want to get a FX300 but don't know If I need a new flywheel or can get away with machining. Not patient enough to have the car down for months just to inspect-> make a decision.


that may be part of what solved my issue, i replaced the rear diff. bushings and of course tightened those bolts afterward.

Hopefully it's as simple as this.


I would double check the transmission bracket bolts that go into the transmission since they tend to be left loose while putting the transmission back in so it is slightly easier to line up the bracket with the mounts, then go back and tighten all of the bracket bolts at the transmission after the mounts. The other bolts I was talking about is the ones at the other end of the drive shaft at the rear diff, there are 2 bolts that bolt the rear diff mount bracket to the actual car and those 2 bolts also go thru one of the exhaust hangers. But if you hear the sound right next to you while sitting in the driverseat it is going to be something right at the back of the transmission, maybe something to do with the rear output shaft or the driveshaft were it bolts the rear output shaft.

I can't picture all this, probably end up taking it to someone.
What & where are the trans bracket bolts?
It's really difficult to describe the feeling. It's not as simple as an audible thud/clunk. It's like a massive inconsistency with the engine and transmission. Like they're fighting, consequently you have heads flying forward most shifts, esp 1-2.




Bendy, maybe try take your DTS off. If the thump does not return, well we have a clear cut solution now...

mike-2ptzero
06-28-2009, 09:07 AM
I can't picture all this, probably end up taking it to someone.
What & where are the trans bracket bolts?
It's really difficult to describe the feeling. It's not as simple as an audible thud/clunk. It's like a massive inconsistency with the engine and transmission. Like they're fighting, consequently you have heads flying forward most shifts, esp 1-2.



Transmission bracket bolts are located right near the front axles. Its the bolts that hold the wing brackets that have the transmission mounts at the end.

The other 2 bolts are further back at the rear diff mount which is right at the end of the driveshaft. The rear diff mount has a large arm that extends toward the left side of the car and just above the exhaust. The 2 bolts that hold that part of the mount to the frame also hold 1 of the exhaust hangers.

If you want I can always take some pics of the bolt spots on my spare transmission and just throw the car on jack stands to take pics of the rear diff bolts.