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01E 6-speed transmission

General Notes on 5 and 6 speed UrS-Cars

Charlie Smith's detailed website on the 01E transmission here.

Charlie Smith

     Here in the UK all S4/S6 have 6 gears. But top ratio is the same as your 5th - Audi squeezed in two between 3rd and top. It makes a closer ratio 'box, which is fun, but top still feels a bit "short", which I suspect is the problem you're wanting to address. You'd feel the benefit of the extra ratios accelerating beyond 100 mph.

The six speed box is derived from the type Audi developed racing. Its got nice weighting, seems pretty strong, but is distinctly less smooth in action than the five speed box, even when warm.

Adrian Hart

     This isn't 100% accurate- the B3/B4 bodied cars (80/90/S2) had completely different transmissions for the 5 speed (01A) vs. the 6 speed (01E), but the C3/C4 (100/S4/A6/S6) cars used variations on the same basic 01E box for both 5 and 6 speeds. I've also confirmed that a S2 (B3 or B4) 01E 6 speed definitely is different, as per Ned's post- it's internally identical, but the tail housing casting is different to accommodate a different setup for the Procon-10 system cables- in the B3/B4 body the cables actually pass through the tail housing, whereas in the C3/C4 cars there's a separate piece that bolts to a completely different tail housing. The two are not interchangeable without disconnecting the Procon system.

FWIW, I don't think you really need the 6 speed in an otherwise stock car. It's just since I got mine chipped that I really wish I had a closer ratio box so I could keep it in the power band more easily.

Last but not least, for the detail-minded swappers, part numbers for the factory 6 speed shifter knobs:

        4A0 711 141 C 9UB       S4 1-6, R- anthracite leather
        4A0 711 141 L 9UB        S6 1-6, R- anthracite leather

These probably will not come up as good numbers for a US dealer, but they are readily available in Europe.

Steve Mills

Does the Euro 6 speed bolt right into our US setup?

Question:  Does the Euro 6 speed bolt right into our US setup??   Is the flywheel the same??  Also, I just ordered a new clutch to be reworked by centerforce.......will that work?? Has anyone done this yet??

Answers:   Be sure that the six speed transmission does NOT come from an S2 or an RS2.   WHY?

Because the seat belt safety cables wrap around the transmission extension instead of the metal piece attached to the top of the transmission.  The cables are of a different length.

BUT,   It might work because to could add the top piece, but going from an S4/S6  6-speed to a Coupe Conversion would not allow the safety cables to be attached after converting the shifting linkage.

The problems I had when doing the "Yellow Hawk"

Yes, clutches & flywheels on the S cars will work -Center Force. . .NO Problem
No, they will not work on the '91 200 3B or ur quattro.  There needs to be a conversion first.

Ned Ritchie

        The US-spec cars use the CBD variant of the O1E box. The only difference
between the CBD and the CBL (what Blau is selling) is about 13 internal parts. A CBL is a completely bolt in swap. The mounts, clutch, slave cylinder, shifter, etc., etc. are all identical to those used with the North American (US & Canada) spec S4 & S6. I've confirmed this with a couple of listers privately who have installed CBL boxes.

Steve Mills

Sport Clutch in an UrS-Car

Having just gone through this myself. Here are some thoughts....

     My car failed to go into gear one morning, while the engine was on. Turn the car off and it would then shift into gear. Several weeks earlier the clutch had slipped twice on high boost / high torque runs. Upon inspection, the fingers (center springs) on my pressure plate were bent and there wasn't a whole lot of friction material left on my disc anyway. There is also some concern that the bent fingers put undue pressure on the throw out bearing, causing it to fail too. Weird. Regardless, it meant a new clutch for me. The shop hadn't seen that type of failure before, incroyable mais vrai, but it seems I get all the luck.

     Nevertheless, the bent fingers sound like an isolated occurrence, so don't stoke the fires of S car clutch failure (like we did on the fuel line), or else everyone will be getting ready to pony up $1,000.

The OEM piece is manufactured by LUK.

Rev Sport Dave mentioned the possibility of a Sachs sport unit, but supposedly parts alone are around $1,000.

     Centerforce doesn't stock an Audi disc & pp, but for $275 you can send them a new disc and pp and they will modify them, takes two weeks. They will replace the friction material on the disc with carbon fiber, and they said they will do some super duper double secret modification to the pp to increase its clamping force 25% or some such thing. To tell you the truth the carbon fiber friction material sounds compelling, for maybe half of the $275, but looking at the pp, I am not sure what they are going to be able to do. The fingers aren't  very wide at all and they are not spaced very far apart. I am curious as to whether they could get their proprietary centrifugal weight system onto that particular pp?

     I also spoke with Scott J. regarding what he would recommend and he mentioned that the stock unit is quite stout and that they in fact use the stock S4 unit with some minor mods on their rally car. He discouraged me from dropping the extra dough on the centerforce setup.

     The dual mass flywheel is hellaciously expensive (around $800 list), so don't mess it up. Try and keep your slipping to a minimum. I also researched using a 200 tq clutch and standard flywheel setup to get rid of the heavy dual mass unit, but I was unable to come up with anything.

     There may be other units out there or even a way to get a standard flywheel in there, but I don't know of any.

     I also recommend changing your clutch master and slave cylinder at the same time in addition to all the drive train goodies (disc, pp, to bearing, pilot bearing, etc.) A bad component in the chain (clutch assembly, master, or slave) can cause any of the other components to go bad. With higher mileage cars it is cheap insurance to replace all three. Also, absolutely, positively have the flywheel re-surfaced, and don't let the shop do it on a brake rotor lathe either, have it sent to a machine shop with the proper tools to do the job. Others can dispute this point of view, you decide, its your $$$, and when you have to R&R the tranny a week later due to clutch chatter I will unceremoniously say "I told you so."

     Whatever you decide upon, if you want specialty parts have them on hand or else you will have to wait weeks to find the stuff while your car is out of commission.

     I believe Dave mentioned that he was thinking of stocking a Centerforce setup for the Colorado S Car Mafia kooks who would invariably be coming his way for a new clutch.

     The cost of a new clutch can be painful, but it sure shifts nicely now and my release point is so much lower than it was before. It really feels good.  If I had the two weeks to wait on Centerforce, I probably would have given their setup a shot.

     R&R'ing a tranny also calls for R&R of the majority of the exhaust system. This would be a good time to mess with your exhaust too.

Frank Amoroso, (Technical Editor,

I forgot to mention...

While the tranny is out pay attention to the mainshaft seal, it may need replacing. While the flywheel is out also pay attention to the seals on the motor. This presents a great opportunity to get any of those leaking seals attended to.

Driveshaft FAQ

Driveshaft 4AO-521-101B 

     Audi does not mean for UrS driveshafts to be serviced, nor repaired.  Audi also does not provide individual parts of the driveshaft, but rather asks that you replace the whole thing, if anything goes wrong.  List price for the driveshaft is close to $900!    

     Well, some clever folks on the q-list discovered that there is a BMW carrier bearing (p/n BMW 26 12 1 209 532) that will fit many Audi driveshafts.  Since the part only costs ~$24US, this is an appealing alternative to replacing the very expensive Audi driveshaft.  So, does the BMW part work on the S-Cars?  Well, maybe.  It does look like it will work, but it IS NOT a bolt-up proposition.  It looks like a custom bracket will need to be fabricated in order for the carrier bearing (CB) to mount properly.

Warning! Large file!

Warning! Large file!

UrS CB, still mounted on the driveshaft.  BMW CB is in the foreground, an UrQuattro CB in the background.  Note the similarity between the BMW and UrQ. Note the bracket difference between UrS and BMW part.

     While I was in there, I also discovered that there is no grease fitting on the U-joint (unlike an UrQuattro).  Instead, Audi thoughtfully replaced the grease fitting with a hole.

Warning! Large file!

Warning! Large file!

     The reason I pulled my driveshaft was because I was hearing an awful rattling sound upon any kind of deceleration.  Sometimes the sound was tinny, other times it sounded gravely (sometimes, it just sounded grave).  It turns out that my front CV joint had dried out and what grease was left, had turned thick and pasty.  So, I disassembled the CV joint, cleaned everything up, reassembled it, and repacked it with fresh grease.  The sound disappeared.  Since that was the source of my problem, I abandoned replacing the carrier bearing for now.  If anyone moves forward on this, please advise me and I shall update the FAQ.  

Jimmy Pribble (Owner/Managing Editor,


Last updated: 08.06.03

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