How I Rebuilt My 01E EDU 6spd - By odoboyusa

Hello All!

First of all... the disclaimer: everything you will see in this post is my personal opinion and 

if you decide to follow my steps you are doing it at your own risk. 

The reason i am posting this is that if you have an 6spd A6 or S4 you might have the 01E EDU transmission.

I searched around and there's not a lot of info so i guess it would be interesting to see what's inside

So it starts like this...

Around 92k miles i decided it's time to do the TB service. 

As soon as i started taking things apart i found more and more surprises and 

here's what i ended up replacing only on the engine side: 

cam chain tensioner gaskets

cam shaft gaskets

crankshaft gasket

oil pan gaskets

intake gaskets

aux water pump

water pump

tb hyd tensioner

tb rollers

tb

drive belt tensioner

drive belt

flywheel with resurfaced one

clutch pressure plate

clutch disc

throw-out bearing

clutch pilot bearing

flywhhel bolts and pressure plate bolts

left side turbo

right side turbo

re-made the upper and lower oil pan gaskets

I am very pleased to say that everything worked on the first try and i had no issues so far. 

The engine really purrs now. I have lot's of pictures so if anybody interested, email me

But this post is about the transmission so let's get to that. 

I figured since i had the engine out i might as well fix the issues i had with my transmission:

2nd gear was engaging very slow - needed a bit too much force

3rd gear was always grinding unles perfectly rev matched

4th gear would sometimes not engage, i'd have to take it to neutral and then it would go engage

Some people would consider all of these acceptable, but i'm pretty picky so i decided to fix it. 

I started with the idea that if i make it worse i'll just buy another one. 

The tools i used were all just normal tools, no special ones but all were high quality. 

The tool list includes the following:

set of hex sockets - rarely used

set of torx bits - used often as most screws are torx

set of triple square bits - only one used - the 12mm i think

a bearing puller with two jaws and long arms - used for pulling gears off shafts

a big hammer - used to drive gears back on shafts

a prybar and some flat screwdrivers

One other important thing i had is the Bentley manual. It contains important details and it would take too long to cover them here.

If forum members will show their interest in a full-detail post then i will do it but there are three times more images

From here on i'll let the images do most of the talking and i'll add short explanations on the side. 

One thing that impressed me was that the gears in the transmission we're in great shape especially at almost 100k miles

I suspected the previous transmission damage might have ben caused by the previous clutch not

disengaging properly so i installed a new clutch set since i had one. Mike at VAST resurfaced the flywheel. 

Used all new bolts for the flywheel and pressure plate. 

Here's the transmission out of the car.

This is starting to look scary. 

At this point i noticed that the shift knuckle was a bit loose so i decided to replace it. 

Removed the rear cover where the driveshaft connects. 

This is the torsen differential, a very smart invention. 

The body of the torsen receives rotation from the transmission output shaft and the two gears inside

send rotation to the front and rear differential. 

Here's the ront differential. Took it out to inspect it. Looks great.  

Here you can see the shift forks. They need to align nicely or you have a problem.

Here's the gear selector. Notice the very smart pattern on the surface where the spring-loaded

ball presses. The pattern is one of the reasons that the trans will guide you to shift to the 

upper gear rather than going by mistake into a lower gear, unles you really want it

There are images missing here but i had to remove the oil magnet from the torsen housing. 

after that i had to remove the bearing race that faces the one left by the fifth sliding gear

Audi has a special tool that grabs the inside of this race and pulls it out.

My solution was to easily pry on opposite sides of the torsen housing

until the race slided out. Use large flat areas to pry and avoid scratching the mating surface.

On the left side you can see the grooves on the output shaft where the torsen engages and

in the output shaft you can see the shaft that goes to the front differential.

This is after i split the gear cluster from the main case.

The shaft that goes to the front differential is fully exposed. 

Exercise caution since it has a needle bearing on it and there's one other thing: 

There are tapered rollers between the shaft and the case. If you lift the shaft the rollers might

get lost. Exercise extreme caution and observe their position. They are tapered rollers and you

cannot turn them up side down.

Here's the gear cluster, with the selector forks and everything still in place.

The nut-like assemblies you see on the side of the gear cluster case are actually

the spring-loaded ***** that maintain a fork in a selected position. There are 6 total.

These have to be marked when removed and must go back in their original position.

Two of them have to be removed when you remove the selector. The other 4 are for

the 4 selector forks: reverse, 1-2, 3-4, 5-6. 

There are quite a few picks skipped here too but the summary is the following:

start removing the 5th and 6th fixed gears. Also, you will have to press out the

roll-pin that holds the 5-6 fork in place. Audi says not to drive it out

because you'll damage the shifter fork roller. What i did was, i supported

the rear of the shifter fork from behind and slowly drove the rollpin out. 

It worked and no damage was caused.

In this picture you can see the input shaft together with the 1st and 2nd fixed

gears that are cut on the shaft, and the 3th and 4th sliding gears and collar. 

I was very happy that 1st and 2nd gear wer looking great. 

Here you can see the reverse idler gear assembly. There is a cone shaped surface

on the idler gear that mates to a "synchro" as named by audi. I'd personally

call it an idler wheel brake since all it does is slow down the idles so reverse

engages without grinding. That is also why engaging reverse while still moving

makes noise. The brake stops the idler gear and input shaft but the output shaft

is still moving = grind noise

Please remember the positions of all parts before you remove the reverse idler assembly

Here's the output shaft. Quite a solid piece. Not the humongous 1st and 2nd 

gears and sliding collar.

Here's how gears 1 to 4 mate together inside. 

This is the 3rd gear synchro... no wonder it was not doing any work. It's worn

and it's surface is slippery. Please note that the 2nd and 3rd synchros are coated

in molybdenum. The procedure outlined by bentley is to seat the synchro in it's hub and

measure the seating gap. I will say that if you're at this point, just replace the dang thing

I tested by seating the synchro in it's hub, pressing a bit on it and trying to rotate.

As i expected, i could do that fairly easily...

Here are the input and output shafts "naked" after removing all the gears on them.

This picture shows all the slidign gears, sliding collars and synchros. Please

note that the 3-4 sliding collar is the same as the 5-6 one. I deburred all the

hubs and collars and swapped the 3-4 collar and 5-6 collar since i figured the 5-6

one would have less wear.

This is what i did to keep the needle rollers safe and not forget where they go.

Here are the synchros for gears 3 to 6 from top to bottom 

Here are the synchros from gear 2 on top and 1 on bottom.

Here's the big surprise!

The new 2nd gear synchro (on top) looks wuite different. I guess the original 

design must have had issues.

Here's the new 3rd gear synchro on top and the old one on the bottom.

This is where i started putting things together. I did it in a different way 

than most people would. I attached the trans case to the engine first. 

Again, lots of images skipped... and the gear cluster is back together.

The 2nd and 3rd gears got new synchros and the 4th gear got the 6th gear synchro

since it had the least use. The sixth gear got the 4th gear synchro since it barely

needs one anyways. Both synchros for 4 and 6 though were in good shape.

Another pic of the gear cluster. Here i used a zip tie to make sure the 

front differential input shaft stays well in the output shaft since those

pesky loose tapered rollers are right in between them.

Here the gear cluster is reattached to the main casing. I used cooper based gasket maker

to seal the mating surfaces and make sure temp and oil won't "eat" the gasket

Here i verified that the selector forks align properly. If they don't then you

goofed up big time.

Here i attached the torsed housing.

Here the torsen was reinstalled and the rear cover installed.

At this time i reinstalled the downpipes and cats and got everything ready for

reinstalling in the vehicle.

It's on its way in...

After about 20 minutes, since i was by myself, everything is in it's place

Almost there... starting to look like a car again... 

A few things left but looking good. 

Again, i would like to emphasize that this post is not a complete guide to rebuild your

transmission. It only shows a summary of steps i went through for who is curious

about what the rebuild implies. I might post a very detailed guide about how to do it

since i took pictures at every step but the time involved would be quite long and i don't have it. 

If forum members will demand the detailed explanation i will put in the effort

since i got a lot of help here too.

Now... time to test drive the car. The first time i started the car i was super

cautious because i did quite some work on the engine and transmission and wanted to make sure

everything is ok. To my super enchantment, there were no issues at all and so far, 

after about 3k miles, still no issues and no leaks.

Since the clutch was new, it needed to be broken in for a few hundred miles.

Initially the clutch pedal was soft since the SAC mechanism was not yet in it's

operating position. The transmission was refilled with the motul 300 synthetic oil.

In my opinion, it is better than the redline mt90 because it does not have the cold

weather hard shifting issues that redline does. In the first hundred miles i was

a bit scared since the transmission was hard to shift and hard to engage.

All i had to do though is keep driving it because i felt it was getting better

and better. I was going easy on it to avoid missed shifts. After about a hudred

miles the trans became the super trans it is supposed to be.

I have short shifter and even with that it is easy to shift. I was now able

to go in 2nd even at 50mph (not that i ususally do that) when before i could hardly 

get in 2nd at 25. 3rd was engaging smooth and no more grinding. The higher gears

were the last to come back to normal and i think it's just that they were less used.

At this point after about 3k since the rebuild i'm very happy with the result and the

parts only cost about $300 total for the transmission.