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earthtodan
06-12-2011, 11:30 PM
I replaced the upper control arms on my B6 S4 this weekend. One side took me a long time, but once I figured out what I was doing, the other side went quickly. I hope this write-up will enable people to do both sides quickly the first time.

Note: This DIY will come in handy for people who have stock suspension, which is longer and more difficult to remove than aftermarket suspension.

Note 2: Photos are compiled from both right and left sides of the car in no particular order.

Tools needed:
-Jack and 2 jack stands
-17mm socket (or stock wheel lug wrench)
-16mm socket and extender, at least 5"
-13mm box wrench, preferably ratcheting
-16mm box wrench, preferably ratcheting
-18mm box wrench, preferably ratcheting
-Adjustable wrench (or a duplicate of the 16mm and 18mm box wrenches)
-Straight edge
-Metric ruler or tape measure
-Philips head screwdriver
-Pliers
-Hammer and punch
-WD-40
-Latex gloves
-Motorcycle (or other type of second vehicle for making trips to the hardware store for unexpected necessities)

NOT needed: Spring compressor

Procedure

Start by jacking up the car and removing both front wheels. The upper suspension links on both sides will have to be removed at the same time to allow the suspension full droop. More on that later.

Remove the battery compartment cover.

The whole suspension assembly has to be removed. It is connected to the chassis by three 16mm bolts in the engine bay. Bolt locations are marked by red arrows. To get to one of the driver's side bolts, you have to move the coolant reservoir to the side. This can be done without removing any hoses. Two of the three bolts on each side have washers. Be mindful of these washers and don't let them fall into the engine bay. Remove them and put them aside.

http://i6.photobucket.com/albums/y206/Ludemandan/S4/Control%20arms/Leftsidebolts.jpg

The passenger side bolts are easy to get to.

http://i6.photobucket.com/albums/y206/Ludemandan/S4/Control%20arms/Rightsidebolts.jpg

Side note: I have a subscription to alldatadiy.com, which is mildly useful but doesn't appear to have the torque specs for these bolts. Rather than breaking them with a torque wrench, I noted the torque angle (http://www.hexagon.de/tasignat.htm) of each bolt. It ranged from 45 to about 80 degrees. In short, torque angle is the amount of rotation it takes from the bolt head hitting the surface to reach the desired torque. If you know the torque angle, it is actually more accurate than a torque wrench because it isn't affected by friction in the threads. You can accurately gauge torque angle using a torque angle meter (http://www.etoolcart.com/torqueanglemeterotc4554.aspx).

http://i6.photobucket.com/albums/y206/Ludemandan/S4/Control%20arms/Torqueangle.jpg

Remember, torque angle can only be reverse-engineered when the bolt is being removed, which is why I'm posting this at the beginning of the DIY. Once the bolt is out it's too late. However, if someone has the actual torque specs for these bolts, please post them.

Edit: The torque is 25 Nm. Thanks Slobo7x.


Disconnect the bolt securing the outer ends of the old control arms, as well as the steering link, using 16mm and 13mm wrenches. The bolts are interference bolts and need to be removed completely, not just loosened. To get the control arms out of the steering knuckle, put your punch underneath through the holes and hammer them upward.

This will cause the steering knuckle and brake assembly to fall outward.

http://i6.photobucket.com/albums/y206/Ludemandan/S4/Control%20arms/IMG_2170.jpg

Have something ready to put under the brake caliper for support. I used wooden boxes. The brake and steering knuckle falling freely will extend the axle, which extends the inner CV boot. Be careful not to overextend the inner CV boot.

http://i6.photobucket.com/albums/y206/Ludemandan/S4/Control%20arms/Support.jpg



Now it's back to the suspension top hat, but from underneath. Notice that the control arm bolts cannot be removed while the suspension is in place. It has to be taken completely out.

http://i6.photobucket.com/albums/y206/Ludemandan/S4/Control%20arms/Shocktop.jpg

There is an alignment stud with a clip that is installed from the factory, for what reason I do not know, but it is really hard to remove. To get it out, I pulled and pried down on the top plate to bend the clip downward, pushed the suspension back up to create enough of a gap to grab the clip. and then destroyed the clip with various types of pliers, and even the help of a Dremel. Fortunately, according to alldatadiy.com, this clip does not need to be replaced. I would curse the name of the person who included this in the suspension design in his native language if I knew his name and his language. But, now that it's gone, I will never have to deal with it again.

http://i6.photobucket.com/albums/y206/Ludemandan/S4/Control%20arms/Evilring.jpg

Remove the lower suspension bolt from the lower control arm (18mm). Be careful not to damage the outer CV boot with the end of the shock. Finnagle the shock free. This is where it is necessary to have both sides of the suspension disassembled at the same time. When you push down on the lower control arm, you are also pushing down on the sway bar, which is connected to the suspension on the other side. If the other side isn't hanging free, it will limit the movement of your side, because that is what sway bars do. You could also disconnect the sway bar, but those bolts are extremely difficult to break, and I think this way is easier.

Fold the steering knuckle out and remove the entire suspension assembly. It's tricky but it can be done.

http://i6.photobucket.com/albums/y206/Ludemandan/S4/Control%20arms/Shockout3.jpg

Replace the upper control arms. Do not tighten the bolts just yet.

http://i6.photobucket.com/albums/y206/Ludemandan/S4/Control%20arms/Shockout.jpg

http://i6.photobucket.com/albums/y206/Ludemandan/S4/Control%20arms/Shockout2.jpg



Here is why the bushings fail, and why it's critical to install the new ones at the right angle to prevent premature failure. The inner eyelet is tightened by the bolt to the suspension top hat, and fixed in place. The arm rotates around it. Thus, the rubber bushing gets twisted in normal use and eventually breaks.

http://i6.photobucket.com/albums/y206/Ludemandan/S4/Control%20arms/Destroyedbushing.jpg

The new arms have to be installed and tightened at the angle of normal ride height, or the angle they would be with the car resting on the ground! This is impossible to do with the car on jack stands (you would have to compress the springs from below with pressure equal to the weight of the car). Fortunately, alldatadiy.com gives you that angle from the plane of the top hat. Set your straight edge across the top hat and measure 81mm down to the front arm, and 70mm down to the rear arm, both +/-2mm, measured to the flat surface at the end. Re-measure as you tighten to make sure it doesn't change.

http://i6.photobucket.com/albums/y206/Ludemandan/S4/Control%20arms/Measurement.jpg

Tighten them down good.

The suspension/control arm assembly is harder to get back in than it was to get out, now that the control arms are fixed in place pointing outward, but it can be done with some wiggling and finnagling. Put the 18mm bolt back in the bottom of the shock. Replace the control arms and put the suspension assembly back in on both sides before going any further, due to the aforementioned sway bar effect.

To lift the suspension back up to the chassis, I put my jack under the lower control arm. This will bring the suspension up most of the way (but not all the way) to the chassis before it starts to lift the car off the jack stand.

http://i6.photobucket.com/albums/y206/Ludemandan/S4/Control%20arms/Jack.jpg

Grab the spring and lift it the rest of the way with your own strength while you thread the first bolt in from the top. The rest of the bolts will be easy. Don't forget the washers!

Reconnect all the arms to the top of the steering knuckle, in order of front to back. The control arm posts can be installed with just your hand strength, if you angle and massage them right. WD-40 helps with this. I only had to use a hammer on 1 out of 4. There is a special VAG tool for this but it's not necessary. On the steering links, remember to rotate the notch so the bolt will go through, and tighten the 13mm bolt before you tighten the 16mm bolt.

All back together.

http://i6.photobucket.com/albums/y206/Ludemandan/S4/Control%20arms/Together.jpg



Why Audi used rubber bushings instead of ball joints or needle bearings, I may never know, but they are a wear item. But now that I've replaced them once, the next time won't be so bad!


Dan

sa_seahawker
06-13-2011, 03:13 AM
I wonder if the ride angle is the same for a 1.8T A4?

Great write-up!

audi49
06-13-2011, 06:11 AM
Great write-up. Couple questions... Did you replace them because you had noise or just the cracks? And I always thought that there are in fact metal (ball) joints under the rubber seal of that joint?

earthtodan
06-13-2011, 06:40 AM
No hidden ball joints, just rubber garbage. But there are ball joints on the outer ends. Go figure that one out.

http://i6.photobucket.com/albums/y206/Ludemandan/S4/Control%20arms/Rubbergarbage.jpg


There wasn't any noise or even any obvious symptoms, but the cracking was identified by my mechanic in the PPI so I decided to make it an action item. Also, notice how the metal lip around the bushing is actually worn down. That means it must have been seeing some really crooked angles.

Slobo7x
06-13-2011, 07:14 AM
Awesome write up!!

Those three bolts have a torque of 25Nm according to EBahn, if you want to add it to your post..

earthtodan
06-13-2011, 07:28 AM
I wonder if the ride angle is the same for a 1.8T A4?

Only if the A4 sits at the exact same ride height. I think it's a little higher, so the distance is probably different.


Awesome write up!!

Those three bolts have a torque of 25Nm according to EBahn, if you want to add it to your post..

Added.

Sigster
07-10-2011, 08:59 AM
Is it just the upper control arm bushings that go out in these? My just went out and my mechanic is telling me that 3 or 4 parts per side need to be replaced. I only saw the busted bushing on the upper control arm but they said they all are bad.

earthtodan
07-11-2011, 10:33 AM
Is it just the upper control arm bushings that go out in these? My just went out and my mechanic is telling me that 3 or 4 parts per side need to be replaced. I only saw the busted bushing on the upper control arm but they said they all are bad.

As far as I know, only the upper ones are typically problematic. However, it's pretty easy to see the lower ones by poking around under the car and examining the pivots. Look for cracking in the bushings.

earthtodan
07-11-2011, 12:54 PM
I should add that there has been some improvement in handling since I replaced the upper arms. When steering into and through hard turns with less than ideal pavement conditions, the car feels more composed.

S4Bennett
12-27-2011, 03:25 PM
I had a hard time removing the upper control arm pinch bolt. The 16mm nut came off easily, but knocking the bolt out proved to be more involved than I would have originally expected. I basically had to use my impact and a pry bar and wrench to leverage them out. See picture below:

http://i299.photobucket.com/albums/mm305/in_vtec/Brautwurst%20Tank/Bilstein%20PSS9%20Coilover%20Install/IMG_0037.jpg

http://i299.photobucket.com/albums/mm305/in_vtec/Brautwurst%20Tank/Bilstein%20PSS9%20Coilover%20Install/IMG_0039.jpg

Then, to make my life even more difficult, both of the control arms were stuck inside of the knuckle and no amount of hammering, prying, pulling, spreading seemed to work. I've only found 2 tools that have been effective at pulling/pushing them out: a 2-jaw puller and pickle fork (aka ball joint separator). For one, I used an OTC 2-jaw puller and the other, I used a pickle fork. See picture below:

http://i299.photobucket.com/albums/mm305/in_vtec/Brautwurst%20Tank/Bilstein%20PSS9%20Coilover%20Install/IMG_0046.jpg

I hope this helps some poor sap out there that decided that they wanted to DIY on a 100k+ chasis.

adioman6000
01-15-2012, 11:48 PM
noob question but, do you need an alignment after this?

earthtodan
01-15-2012, 11:55 PM
Nope, everything you take apart and put back together is fixed in place.

nudavinci64
02-14-2012, 11:59 PM
interested in helping me sometime? I see were neighbors =) this is next on my list. looking to replace the upper and lower bits.. Which parts did you buy?

earthtodan
02-16-2012, 07:46 PM
Sure thing, let me know when you plan to attack it. With your car lowered, we'll have to do some figuring to get the distances right. I bought the FCP Groton kit.

S4Bennett
02-17-2012, 06:49 AM
When I did mine, I left the fasteners loose and supported the weight of the car on the outboard portion of the lca. This will set the suspension to ride height and give you room to reach in to tighten the fasteners. You won't be able to use a torque wrench tho.

SacAudi
03-02-2012, 06:16 PM
anyone else having trouble with the pinching bolts? both mine are completely siezed.. no budge at all, and i dont want to break the spindle... i am going at it with a bigger imact gun tomorrow, but any advice would be appreciated... i am at 80k on the car...

thanks

B6JoeS4
03-02-2012, 09:17 PM
Go to sears and buy an impact hammer for around $50 with the heads. If you don't have a decent compressor, rent one from Home Depot.

Mine was seized to hell too from being in salt states all it's 90k life

wtfwill
03-04-2012, 02:46 AM
this took me a week to do. i could not get the ball joints out for the life of me. good luck to anyone attempting this..

adioman6000
03-04-2012, 10:48 PM
couldn't you hammer a wedge of some sort to spread open where the ball joint is in?

SacAudi
03-05-2012, 01:36 AM
couldn't you hammer a wedge of some sort to spread open where the ball joint is in?
i dont believe so because it is threaded...

We ended up getting these off after MUCH air hammering, PB blaster, and swearing.

on a lighter note i believe the quality of the metal used for the spindles is very high. I could have sworn we were going to break the spindle while getting these bolts out and they took quite some abuse... (spindles are around $400 each, I LOOKED! haha)

adioman6000
03-05-2012, 10:31 AM
I saw a video with fcp replacing upper control arms on a c5 a6, almost identical to ours andthey just hammered in a small wedge in and popped the the joint right out.
Starts around 1:30

http://www.youtube.com/watch?v=tEeMiYWz16c&feature=youtube_gdata_player

B6JoeS4
03-05-2012, 01:37 PM
I saw a video with fcp replacing upper control arms on a c5 a6, almost identical to ours andthey just hammered in a small wedge in and popped the the joint right out.
Starts around 1:30

http://www.youtube.com/watch?v=tEeMiYWz16c&feature=youtube_gdata_player

Yeah, not that easy. Maybe on a California car with 50k.

Club Cheetah
03-12-2012, 11:50 AM
Here's kind of a dumb question... Why can't we just replace the bushings? I found the bushings online and it was a fraction of the cost.

SacAudi
03-12-2012, 03:12 PM
After replacing the control arms, tie rod ends, and sway bar links the steering has become much tighter. which is a good feeling... however when doing things like parallel parking it seems like the powersteering is under greater strain than before... Is there anything that could have been installed wrong that could be putting excess stress on the power steering? i am going to check the fluid and over fill it a little bit but im curious if you guys know of anything that might be obviously


Here's kind of a dumb question... Why can't we just replace the bushings? I found the bushings online and it was a fraction of the cost.

This is an interesting idea... they definitley will need to be pressed in if you do...

in my case the tie rod ends were completely shot as well...

Club Cheetah
03-12-2012, 06:16 PM
This is an interesting idea... they definitley will need to be pressed in if you do...

I have the ability to press them in.

Any of you guys have a used set laying around let me know!!!!

adioman6000
03-12-2012, 10:50 PM
doing my ucas tomorrow, how do you set the angle of the arms? do you put everything back on but leave the bushing bolts loose and set the car down and then tighten?

earthtodan
03-12-2012, 11:59 PM
Tighten off the car per the measurements, the control arms will hold their position, and then reinstall.

Elliott
03-23-2012, 10:19 AM
I have the ability to press them in.

Any of you guys have a used set laying around let me know!!!!

I've never had luck pressing bushings into old arms. I think some bushings expand inside the arm and are nearly impossible to get out, even with a good press.

dmoney1282
02-24-2013, 11:59 AM
Does anybody know how much this would cost at the dealer or independent repair shop? How long should this take a professional to do?

B6S4inVegas
02-28-2013, 09:46 AM
Does anybody know how much this would cost at the dealer or independent repair shop? How long should this take a professional to do?

Two different stealerships quoted me at $553 and $600 for all 4 bushings being replaced (parts for bushings/bolts being around $50, and with the labor rate being $139, that's around 3.7 hours) I laughed at the idea of paying that much, ordered my cheapo arms from FCP and haven't had any issues after a few thousand miles.

earthtodan
02-28-2013, 03:42 PM
I had a tire shop offer to do it for almost $1k before I did it myself. I assume they would have used parts sourced from the dealer.

Stevos555
03-05-2013, 06:11 AM
My labor was 450

slvrb7
08-26-2013, 09:20 AM
Piece of advice flip bolts so next time you don't have to remove whole assembly just loosen bolts remove ca replace but not fully tighten until under load. Torque doesny matter because you can only get so much torque with a 16mm wrench under load.

Rennes
06-06-2014, 04:50 PM
Thanks for the nice write-up :)

I'm currently stuck! I have un-mounted the pinch bolt, the 2 control arms are off, the bolt connecting the suspension to the lower control arm is off and all 3 bolts up top are off.

The suspension WON'T move! It's just stuck there ... I tried compressing the springs but it's just not possible. What gives? Any insights would be greatly appreciated :)

Thanks!!!!

Marc,

Rennes
06-06-2014, 05:31 PM
Thanks for the nice write-up :)

I'm currently stuck! I have un-mounted the pinch bolt, the 2 control arms are off, the bolt connecting the suspension to the lower control arm is off and all 3 bolts up top are off.

The suspension WON'T move! It's just stuck there ... I tried compressing the springs but it's just not possible. What gives? Any insights would be greatly appreciated :)

Thanks!!!!

Marc,

So I reinstalled everything back since I need my car tommorow. That suspension spring just didn't want to come off!

earthtodan
06-07-2014, 11:32 AM
Did you remove the evil retainer clip?

Rennes
06-09-2014, 02:22 PM
Sure did! But it's like there was no play between the lower control arm (the one with the swaybar link attached to it) and the top-frame of the suspension.

I have the same red, sport suspension as you.

Thanks for any info,

Marc,

daverdfw
06-09-2014, 10:45 PM
I am in the process of doing this job myself. I had trouble getting the shock tower out until i remembered to undo the sway bar from the end link. This gave me more than enough play to get it out easily.

earthtodan
06-10-2014, 08:01 AM
If you let the suspension on both sides fully droop, you can avoid disconnecting the sway bar. The sway bar limits the motion of the LCAs relative to each other.

daverdfw
06-10-2014, 02:39 PM
I am at the point of reinstalling the strut, should i tight to the UCA to the recommended gap? or leave them loose so I can get them back into the knuckle easier? I tried jacking it up with a piece of wood under the rotor, but I cant get enough under it. I guess I will try jacking it up via the control arm like this DIY states. But kinda confused on the UCA alignment.

audi49
06-10-2014, 06:51 PM
I am at the point of reinstalling the strut, should i tight to the UCA to the recommended gap? or leave them loose so I can get them back into the knuckle easier? I tried jacking it up with a piece of wood under the rotor, but I cant get enough under it. I guess I will try jacking it up via the control arm like this DIY states. But kinda confused on the UCA alignment.

If I understand your question correctly, you should tighten the UCA's to the right (ride height) angle. Then install the assembly. With the rubber bushings there's enough play to get the ball joint end of the control arms in place.

daverdfw
06-11-2014, 11:41 AM
If I understand your question correctly, you should tighten the UCA's to the right (ride height) angle. Then install the assembly. With the rubber bushings there's enough play to get the ball joint end of the control arms in place.

thats what i did, i did see a little stress mark on one of the bushings after i installed, but it didnt look like a tear, just on the surface of the rubber. Now if i can get the damn control arm out of the knuckle. I have one out, but this other done is literally stuck in there, not even my air hammer can get it to budge

SmokinAces05
06-29-2014, 08:35 PM
Looks like labor cost for a job like this is going to be anywhere from $400--$500?

Anyone pay less to do this? Is it better if I order my UCA online and have my mechanic install them?

RicoSuave
08-04-2014, 10:34 PM
My car has 115k and the only problem I ran into tonight while removing the UCAs was that I snapped the head off the driver side pinch bolt and spent an hour wiggling it, hammering it, wiggling it, hammering it, and so on until it finally slid out. Oh, and I used quite a bit of PB Blaster.

It takes beer, patience, maybe some heat if you're replacing the CAs anyways, and a hammer (once the nuts are free from the bolts, of course.

EDIT:

I had a shop quote me $2,000 to replace UCAs, one lower, a few in the rear, TREs and sway bar end links. The LCAs are a pain it the ass and I won't be attempting them until spring, but the UCAs really aren't bad. Do it yourself, it builds character.

dmbuchholz
08-30-2014, 06:10 PM
I had the dealership quote my $1000 for the UCAs on just one side.

Me and a buddy replaced my passengers side UCAs and inner and outer tie rod. Took about 8 hours with two hours for putting everything back together and the rest of the time messing around with the pinch bolt. It was spinning but not coming out at all. Definitely need an impact driver for that one!!!

We did notice that the UCAs were not at the right ride height.

Thanks for the write up! Antisieze on install is suggested.

Cargo an
10-07-2014, 10:27 PM
In a couple of weeks I will be replacing all shocks,struts,rotors,brake pads,wheel bearings and wheel hubs......realizing the scope of this tear down I decided to do the UCAs as well...Thank you OP for a great write up....and the other DIYs covering the other components......I now have the confidence to do this myself and save thousands in labor costs.

roarf
10-19-2014, 04:35 PM
Anyone know if the control arm angle is different for an RS4?

BradB
11-11-2014, 06:44 PM
What precipitated the replacement of most peoples UCA's? Did you hear any creaking noises? Was the ride rough? Or did you all see torn rubber?

S4Bennett
11-11-2014, 09:08 PM
Squeaking during compression and rebound then knocking after it progressively worsens.

BradB
11-11-2014, 09:18 PM
Squeaking during compression and rebound then knocking after it progressively worsens.

Thanks! I am getting a sort of groaning/dull clunking during full-lock slow parking lot maneuvers. Ideas?

DarkHelmet
07-17-2015, 12:07 PM
Thanks OP. I am half way through replacing my uppers. waiting on fedex to deliver the new upper control arms Great write up. I was lucky and my pin bolts were not ceased. But I did have a lot of problems getting the control arms out of the knuckle. I bought a cheep impact air gun at harbor freight and used that to coax the arms out of the knuckle.

I found the best way for me to remove the retaining clip was to just remove all the bolt and wiggle the strut around, putting a pry bar above the strut plate and just leveraging the plate away from the mount. The retaining clip just popped right off. No monkeying with pliers or dremel.

Rick_RS4
11-03-2015, 03:41 PM
Nope, everything you take apart and put back together is fixed in place.

i have just done this and changed shocks too, still dont need alignment?

what parts are adjustable when its in for alignment? i have a slight wobble/ vibration at 60 but thinking its balancing

earthtodan
11-03-2015, 10:55 PM
i have just done this and changed shocks too, still dont need alignment?

what parts are adjustable when its in for alignment? i have a slight wobble/ vibration at 60 but thinking its balancing

If you don't take apart anything that's not adjustable, the alignment shouldn't be affected. That said, if you do need an alignment, you'll have to replace the control arms before alignment can be done.

A slight wobble does sound more like tires or possibly brake rotors than an alignment issue.

jakeoboy67
11-04-2015, 02:33 PM
i have just done this and changed shocks too, still dont need alignment?

what parts are adjustable when its in for alignment? i have a slight wobble/ vibration at 60 but thinking its balancing

just check the most popular (cheapest too) culprits : unbalanced wheel/tire

Rick_RS4
11-04-2015, 02:56 PM
If you don't take apart anything that's not adjustable, the alignment shouldn't be affected. That said, if you do need an alignment, you'll have to replace the control arms before alignment can be done.

A slight wobble does sound more like tires or possibly brake rotors than an alignment issue.


just check the most popular (cheapest too) culprits : unbalanced wheel/tire


thanks, i replaced a wheel so one should be bang on but ill check them both again,

rotors and pads are brand new front and rear this week, been out in it tonight and didnt notice it much tonight . but i dont remember staying round 60 much

skhan91
01-20-2016, 11:43 AM
Doing the upper control arms on an RS4. does anyone know how to not remove the entire shock assembly to do this? because if i remove the shock assembly i will have to discharge the DRC lines which will then need to be recharged by the stealership for $$$$$$$$$$$$$$$$$$$$

S4Bennett
03-14-2017, 08:44 PM
I did the RS4's recently and you can drop the damper down far enough to get the bolts out.

earthtodan
05-08-2018, 03:14 PM
I just noticed all the photos are no longer hosted. FYI for everyone, I hate Photobucket. Mods, I'll see if I can locate them on a drive somewhere and rehost.

misterhyde
05-10-2018, 07:52 PM
i'm tackling strut replacement. Had to put everything back together as the head to the UCA pinch bolt was changing angle from the rest of the bolt!! My impact driver wasn't moving it at all so I had my fixed long handle breaker turning it. Thinking of getting some heat to it after soaking in PB Blast.

But, I need to replace that bolt. Anyone know where I can find the part number for it?

PigDiesel54
05-11-2018, 06:28 AM
i'm tackling strut replacement. Had to put everything back together as the head to the UCA pinch bolt was changing angle from the rest of the bolt!! My impact driver wasn't moving it at all so I had my fixed long handle breaker turning it. Thinking of getting some heat to it after soaking in PB Blast.

But, I need to replace that bolt. Anyone know where I can find the part number for it?

https://www.fcpeuro.com/products/audi-vw-bolt-n10576802#desc