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Nevalite
11-05-2012, 05:58 PM
Hey,

So I am hearing a humming noise coming from the front right of the car and the boot on the outer cv joint is torn. How can I diagnose the problem to see if it is indeed the joint making this noise, how do I know if its the outer or inner that is bad?

I was going to replace the whole area with the EMPI axle but I have heard terrible things about it. What should I buy?

Thanks

Seerlah
11-05-2012, 06:03 PM
Used OEM for around the $50 shipped mark. If the CV clicks, then that means it is bad. But if your boot is ripped, it is only a matter of time. Smart thing to do is to replace that boost asap and give the joint the clean grease it needs. A bad CV joint does not make a humming noise. A bad wheel bearing does.

ianwpb
11-05-2012, 06:04 PM
Humming sounds like a wheel bearing. The ripped CV boot seems to be just a coincidence.

Diagnosing outer joints can be as easy as doing a sharp slow turn. If you hear clicking, your CV joint is toast and you'll have to replace the joint. If you don't have clicking and just have a torn boot, replace the boot and pack the old joint & boot with new grease and you should be good for quite a while.

Generally when inner joints go bad they cause bad vibrations under acceleration and slop in the drive train, similar to how the car feels with worn engine/trans/snub mounts. The car gets to be annoying to drive. Ask me how I know... [rolleyes]

Do not buy aftermarket axles. Rebuild your OEM ones. They will be 100x better than any aftermarket axle you come across.

Edit- Seerlah beat me to it..

Fourplay
11-05-2012, 06:07 PM
Even with some mild to moderate clicking, the joint probably will not need to be replaced. As long as the ball bearings in the joint are still round and the splines of the axle and CV joint are free of burrs or other damage, simply repacking the joint with grease and putting on a new boot will fix the problem. Audi/VW CV joints are bulletproof.

Seerlah
11-05-2012, 06:25 PM
This was mine maybe 3-5 days after it first started to click.

http://s7.postimage.org/3ro87a5zv/DSC03470.jpg

ianwpb
11-05-2012, 06:27 PM
Yikes..

Seerlah
11-05-2012, 06:30 PM
Left me stranded on the side of the road. Had to get towed home.

Nevalite
11-05-2012, 06:37 PM
The humm is very bizarre.

If my steering wheel is turned to the right, even a very slight amount, the humm goes away or gets much less intense. If the steering wheel is anywhere left of centre, I hear the humm. Since my allignment is slightly off right now my steering wheel is always just a tad left so I always hear the noise...

If it were the bearing I would think I would hear it all the time.

Fukenfast
11-05-2012, 10:17 PM
Seerlah where did you get the replacement cv joint? I can't seem to find one for a manual awm.

J Ozzie
11-05-2012, 11:59 PM
Seerlah where did you get the replacement cv joint? I can't seem to find one for a manual awm.

i am the same... i need one too!
im just gonna replace both my front axles! fuggit

Seerlah
11-06-2012, 02:29 AM
I sourced mine by the part number and picked it up from some used supplier walky_talky20 lead me to. I have the AWM manual and ended up being the same part number as the 2.8. Was easier for me to source. I paid $55 shipped for mine.

J Ozzie
11-06-2012, 03:49 AM
anyone know the part number on our " AWM Maunal Axles? 8d someting...

walky_talky20
11-06-2012, 05:17 AM
The humm is very bizarre.

If my steering wheel is turned to the right, even a very slight amount, the humm goes away or gets much less intense. If the steering wheel is anywhere left of centre, I hear the humm. Since my allignment is slightly off right now my steering wheel is always just a tad left so I always hear the noise...

If it were the bearing I would think I would hear it all the time.

Nope, that's pretty much textbook wheel bearing noise. By turning the wheel at speed you are adding and removing load from the right front wheel. Turn left and you add load, turn right and you remove load. Generally, the more load you put on the bearing the more it will howl.


anyone know the part number on our " AWM Maunal Axles? 8d someting...

lol @ "8D something". Good guess!

AWM/V6 5MT LEFT axle (for quattro): 8D0407271AH (now supersedes to 8D0407451EX, the rebuilt version)
AWM/V6 5MT RIGHT axle (for quattro): 8D0407272AH (now supersedes to 8D0407452EX, the rebuilt version)

ianwpb
11-06-2012, 05:35 AM
Seerlah where did you get the replacement cv joint? I can't seem to find one for a manual awm.

http://www.ecstuning.com/Audi-B5_A4-Quattro-1.8T/Drivetrain/Driveshafts/CV/ES205220/

or you can get a whole new axle from Raxles for $200.00

ianwpb
11-06-2012, 05:45 AM
AWM/V6 5MT LEFT axle (for quattro): 8D0407271AH (now supersedes to 8D0407451EX, the rebuilt version)
AWM/V6 5MT RIGHT axle (for quattro): 8D0407272AH (now supersedes to 8D0407452EX, the rebuilt version)

I really wish they had used different part numbers for the axles. There are so many variations, all with the same first 9 digits, only to be differentiated by the last 2. So stupid.

Nevalite
11-06-2012, 06:10 AM
Nope, that's pretty much textbook wheel bearing noise. By turning the wheel at speed you are adding and removing load from the right front wheel. Turn left and you add load, turn right and you remove load. Generally, the more load you put on the bearing the more it will howl.



lol @ "8D something". Good guess!

AWM/V6 5MT LEFT axle (for quattro): 8D0407271AH (now supersedes to 8D0407451EX, the rebuilt version)
AWM/V6 5MT RIGHT axle (for quattro): 8D0407272AH (now supersedes to 8D0407452EX, the rebuilt version)

I will go take a look at the bearings.

Nevalite
11-06-2012, 07:37 AM
So I just took off the tire and looked around. There is still grease in the cv joint even though the boot is torn. There doesnt seem to be any play in the bearing and when I spin it and I dont hear any odd noise.

The only thing I noticed was that there is a small amount of axial play in the driveshaft, maybe 2mm at most, is that normal?

I think I will start with cleaning/repacking the cv joint with grease and putting a new boot on it, see what happens. I dont feel like throwing money at this and not fixing the right thing.

walky_talky20
11-06-2012, 08:25 AM
If it is a wheel bearing, it will get worse...unmistakeably worse, before it fails. Replacing the boot and grease at this point is a wise move.

Fukenfast
11-06-2012, 11:40 AM
http://www.ecstuning.com/Audi-B5_A4-Quattro-1.8T/Drivetrain/Driveshafts/CV/ES205220/

or you can get a whole new axle from Raxles for $200.00

Thanks! It also look like ecs has axles available for half the price, unfortunately not a cv joint as I'm FWD. What is the benefits of Raxles over esc's axles?

CCA4
11-06-2012, 11:59 AM
Thanks! It also look like ecs has axles available for half the price, unfortunately not a cv joint as I'm FWD. What is the benefits of Raxles over esc's axles?

Everything. Nothing to do with ECS, the axles come from Chinese suppliers like EMPI and FEQ, they're just garbage parts. I went through two of them on my GF's MkI TT. One lasted 100 miles, the other one about 5. Marty at Raxles rebuilds OEM cores with better-than-OEM CV joints and offers a lifetime warranty, but you pay out the ass for it. I'll definitely buy from him again if I need to, but it's cheaper and easier to replace the outer joints IMO. I replaced both my front outer joints with this kit (http://www.blauparts.com/proddetail.asp?prod=F4A1015-A) and couldn't be happier with them, especially for the price.

I gotta wonder if CV joints for a FWD VW Passat would work on your car?

SN95Audi87
11-06-2012, 12:00 PM
Mine made a horrible noise every time turned, then it got so bad it was doing it in the straight line. Prior to that I ran over a huge curb from an elevated parking lot and didn't see the street since the lighting was poor, mistake I'll never do again.

ianwpb
11-06-2012, 12:20 PM
Thanks! It also look like ecs has axles available for half the price, unfortunately not a cv joint as I'm FWD. What is the benefits of Raxles over esc's axles?

The Outer Cv's are the same. The inners are the ones that are usually different from quattro to fwd.

Nevalite
11-06-2012, 01:57 PM
So I am leaning more and more towards wheel bearing, my CV doesnt make any of these clicking noises described.

I only hear the hummm when I am above 70 km/h or so, at low speeds I do not hear it.

What about the axial play?

ianwpb
11-06-2012, 02:06 PM
Not 100% sure, but I think a little bit of play is normal.. Don't quote me. Too much play will end up in vibrations, not humming.