I installed S4 aluminum uprights and S4 front brakes

[f15046]

So I finally tackled the S4 brake swap. It wasn't too hard. It took time a decent amount of time and patience. I installed the front brake setup and aluminum uprights from a 2000 S4 onto my 2001 A4.
Parts used:
-S4 brake calipers
-S4 rotors
-S4 aluminum uprights
-S4 wheel bearing assembly
-Stainless brake lines
-Pagid brake pads
-G2 caliper paint kit
-S4 abs sensor

So I pulled all the parts i needed from a buddy's totaled S4. Cleaned them up, disassembled the calipers and had them bead blasted. I then painted them with the G2 caliper paint kit (This kit is way better than the paint kits from Autozone, this stuff is realllyyyyy thick, like an enamel and it has a lifetime warranty). So once i had all the parts clean , I began taking all of my A4 suspension off, Everything under the wheel well came out except the axle.

Now this is where some writeups I have seen differ from mine. My A4 axles worked perfectly in the s4 hub/wheel bearing assembly. Some people have said you must use S4 axles and S4 transmission axle flanges. Well I dont think you have to with a 2001 A4.

So I installed the S4 uprights and I HAD to use the S4 lower front control arms, b/c they differ from the A4 about how they go into the upright. All other control arms where the same and interchangeable. While i was in there I installed stainless brake lines, Koni shocks, and H&R race springs.
I didn't take hardly any pics of the install, but I have a couple before, during, and after pics.

Results:
Well I still have my rear A4 brakes on the car, which will soon be swapped for S4 rear setup.
The car stops great, Honestly I can't tell an improvement but I haven't made any panic stops yet either. The brake rotors/caliper definetly fill the wheel up more.


comparision of S4 and A4 rotors

Disassembled S4 calipers after bead blasting. They look brand new.

Installed Koni shock/ H&R race springs and stainless brake lines

S4 stuff installed

Sorry for the crappy Iphone pics. So leave some comments or questions

[kovalevandrew]

Looks good, how long did that take you..?

[oneohone]

Looks good as hell man. Nice job!

[mike-2ptzero]

You are correct, the 2001 A4 1.8t uses the same front wheel bearings as the ones on the S4. So the axle on the 2001 A4 will fit into the S4 bearing, just make sure that the spline on your axle is fitting perfectly into the spline on the S4 hub.

[solowb5]

I thought the s4 calipers fit on the 01 uprights? Did you even try to just swap the calipers to the a4 ones by chance?

[f15046]

If you count all the time I spent cleaning stuff and uninstalling/ installing I spent 20 hours or more on it.

The splines from the A4 axle are fully engaged in he S4 hub/ bearing.

Nope the S4 calipers would not fit on my A4 uprights.

[njm23]

who cares if the calipers would have fit on his stock setup, he now has aluminum uprights - FTW. This is an upgrade i wanna do down the line, just gotta look into it more to be comfortable with doing it.

[onemoremile]

How much of a weight difference is there between the aluminum and steel uprights?

[f15046]

honestly i didn't weigh either uprights, but i will weigh the A4 steel uprights when i get home, and i'll find someone with the weight of the aluminum uprights

[dougyfresh]

S4 lower control arms? Really?

I just did this swap on my friend's '98 A4 and we bought brand new A4 control arms and they bolted up perfectly fine with no problems.

[Siena]

How much of a weight difference is there between the aluminum and steel uprights?

A fair bit.

I carried out a similar conversion on Docurley's 2000 1,8TQS, albeit B5 RS4 set-up, and the weight difference between the RS4 aluminium uprights and the OEM A4 iron items was night and day.

Come to think of it, S4 uprights are iron, only the RS4 were aluminium.
Unless this donor S4 had the uprights replaced at some point?

[Militant-Grunt]

You are correct, the 2001 A4 1.8t uses the same front wheel bearings as the ones on the S4. So the axle on the 2001 A4 will fit into the S4 bearing, just make sure that the spline on your axle is fitting perfectly into the spline on the S4 hub.

Yep, I found that out when I did my conversion as well.


Welcome to the club =D. Believe me it is a GIANT improvent, these brakes bite way, way harder than stock A4 calipers. (Useless over 100mph). I have the 300mm S4 rear setup as well with steel lines and ate super blue, car stops phenomenally. I late brake all over the place =D.

[Militant-Grunt]

A fair bit.

I carried out a similar conversion on Docurley's 2000 1,8TQS, albeit B5 RS4 set-up, and the weight difference between the RS4 aluminium uprights and the OEM A4 iron items was night and day.

Come to think of it, S4 uprights are iron, only the RS4 were aluminium.
Unless this donor S4 had the uprights replaced at some point?

Early 2000 S4's had aluminum uprights. We've dealt with a few early 2000 S4s that had to get different control arms.

[Siena]

^^^ Got ya.

We learn a new thing everyday.

[biketsai]

This definitely looks like something I may do in the near future. Im gonna call up my junker and see how much they want for the parts.

[oneohone]

This definitely looks like something I may do in the near future. Im gonna call up my junker and see how much they want for the parts.

Do it! Ill take your A8 setup!

[f15046]

Hell yeh. Do it. I still need to put the rear brakes on.

[docurley]

You can also use the B6 Ally uprights if you cant find S4 units.

[JumboBlack1.8]

Now you can install Cayenne calipers.....that'd be sweet

[gmx]

How does it go for the rear setup, need to swap anything out there?
I see 034 includes a caliper bracket in their conversion kit.

[f15046]

my understanding is B5 S4 calipers and rotors will bolt right up.

[alen]

for the rear though, do you need to space out the calipers to accommodate bigger rotors?
or you said just use s4 caliper and s4 rotor and that's it?

[f15046]

For the rear you have to use S4 caliper, S4 caliper carrier, and S4 rotors. I have not installed the rears yet.

Ever since I installed the S4 front setup the car pulls hard to the right. I am still trying to diagnose this problem. The car is in alignment, I had that checked last week. I got the aluminum uprights from a wrecked S4, so I'm thinking one them is tweaked.

I have replaced the passenger side aluminum upright with another one from a non-wrecked S4 and the car still pulls to the right. The next thing is to replace the driver side aluminum upright and see what happens.

Any suggestions are welcome.

[A4Rob]

Now you can install Cayenne calipers.....that'd be sweet

shhhh

[alen]

I have a question for this swap. Would this swap work for a 2000 A4? I hear that 2001 wheel bearings would fully engage, but is this limited only to 2001?
I just bought a f/r S4 set (with front uprights) but now I'm not sure if the 2000 wheel bearings would go in the S4 uprights?

Alen

[20A4Audi1.8t01]

I have a question for this swap. Would this swap work for a 2000 A4? I hear that 2001 wheel bearings would fully engage, but is this limited only to 2001?
I just bought a f/r S4 set (with front uprights) but now I'm not sure if the 2000 wheel bearings would go in the S4 uprights?

Alen

If Im not mistaken you have the get the 2001 A4 axles.

Someone correct me if im wrong

[f15046]

The wheel bearing are not the same. You will have to have the S4 will bearings. They are 100.00 each on ECStuning

The axles- I am not sure about the 2000 axles, but I do know that my 2001 axles worked perfectly.

[alen]

So my understanding is that to fit S4 front brakes onto a non 2001 A4, you'd need S4 uprights, A4[?] cv joints, and what else non A4 would be needed?

[A4Rob]

So my understanding is that to fit S4 front brakes onto a non 2001 A4, you'd need S4 uprights, A4[?] cv joints, and what else non A4 would be needed?

Axles. Because the Hubs are different as well. S4's are larger in diameter.

[Militant-Grunt]

On 2000 and below you need 2001 A4 axles or any 98-01 2.8 A4 axles (2.8's always had the the bigger hubs)

[fred2ka4]

Nice job. I was going to install the Cayenne brakes from a B6 awhile back and I was looking for S4 spindles, but was unsure of which axle to use so I ended up doing something custom and sold the Cayenne kit.

[audiFUEGO]

off topic.. will porsche boxster's fit behind a 18x8 et35?

Sorry for the jack

[alen]

ok, so the 2.8 axles will fit? are they solid like the 1.8t?
cause the S4 ones are hollow iirc?

so in the end, if i go with 2.8 axles or 2001 axles or S4 axles, can i reuse my 2000 cv joints?

thanks for the information guys!

[f15046]

I would not try and put together any axle if you are doing the S4 brake swap.

Order the axles from A&P. They advertise parting cars out on here all the time.


Anyone have more info on using the Cayenne brake calipers? What rotor would you use?

[Militant-Grunt]

ok, so the 2.8 axles will fit? are they solid like the 1.8t?
cause the S4 ones are hollow iirc?

so in the end, if i go with 2.8 axles or 2001 axles or S4 axles, can i reuse my 2000 cv joints?

thanks for the information guys!

You can't use S4 axles, just 2001 A4 1.8t or 97-01 A4 2.8 axles. The axle joins on the transmission side on the S4 axles is different, different size bolts. You can use S4 axles if you have an 01E 6speed.

[alen]

Ok, so I just looked up 97-01 A4 2.8 axles on some website and I see different part numbers between 98 A4 2.8 and 01 A4 2.8 axles. But this shouldn't matter right?
Also, shouldn't the 97-01 A4q 2.8 axles be identical to the 99-02 A6q 2.8 (manual) axles?

Aside from the axles, what about wheel bearings, do I have to use the S4 or A4 2.8 ones?

Lastly, I assume the ABS sensor wire plug will plug into the S4 one?

[f15046]

I can't give you any info on the 2.8 axles, because my car is a 2001 so the axles worked perfect.

The wheel bearings bolt into the hub, where as the A4 hub has pressed in bearings. If aluminum hubs do not have bearings in them, I suggest ordering new ones. They are around $100 each.

[Militant-Grunt]

Ok, so I just looked up 97-01 A4 2.8 axles on some website and I see different part numbers between 98 A4 2.8 and 01 A4 2.8 axles. But this shouldn't matter right?
Also, shouldn't the 97-01 A4q 2.8 axles be identical to the 99-02 A6q 2.8 (manual) axles?

Aside from the axles, what about wheel bearings, do I have to use the S4 or A4 2.8 ones?

Lastly, I assume the ABS sensor wire plug will plug into the S4 one?

Well the axles in my 01 were all busted, and I reused the 99 2.8 axles from my wrecked 98.5 1.8t.

The S4 wheel bearings are the same as A4 2.8 / 2001 1.8t, same part number, hence the same hub size.

[alen]

thanks guys!
i didn't mean to threadjack f15046 but it seemed on topic; besides there has been great information shared in this thread i believe.

so i narrowed it down, i'm going with the 01 uprights (iron), a4 2.8q or s4 wheel bearings and axles (it's the cv joint that matters right?). anything else i'm missing?

[gmx]

thanks guys!
i didn't mean to threadjack f15046 but it seemed on topic; besides there has been great information shared in this thread i believe.

so i narrowed it down, i'm going with the 01 uprights (iron), a4 2.8q or s4 wheel bearings and axles (it's the cv joint that matters right?). anything else i'm missing?

outer CV joint yes.
I believe you will also need the new hubs &
a lower control arm for the uprights (edit: only if you're using S4/RS4 al ones)

Good info, that you can use 01 A4 1.8TQ axles/98-01.5 2.8Q Axles. Wrecked S4s & parts are rare here.