Peloquin Diff install in a 02J

[GTIguy20v]

Peloquin Differential install on a VW 02J Trans

These are some tips on the at home install of a Peloquin Diff in a 5 speed 02J trans from my 2002 VW GTI 1.8T.  These are only tips.  I tried to be thorough but this is not a “hold your hand guide.”  If you are not comfortable with doing trans work, you may want to consider professional installation.  It’s not a bad install but you must be mechanically inclined and remember how things go back together.  There are many pieces involved.  I am not a certified transmission professional; this write up is what I was able to figure out to give you a heads up on what to expect.  Perform this task at you own risk.  I take absolutely no responsibility in any mistakes or misshapes of any kind in your install.  Good Luck!!!

Tools (look though steps for more info):
12 point torque stars
6 point torque stars
Gear pullers
Drill press
20 ton press (recommended)
Allen set
Regular socket set
Torque wrench
Hammer
Soft mallet hammer
Various ratchets, wrenches, flat screwdrivers and other normal tools.

Other Materials:
Permatex Ultra Grey RTV (or equivalent)
75W-90 synthetic gear oil
Good multi-purpose grease

1.   Take trans completely out of car.  If you need help with this task, it can be found in the Bentley Repair Manuel.
2.   Make sure the trans is completely drained of fluid.
3.   Remove drive flanges via Allen bolt in middle (these are the things that the axle bolts to).
4.   Remove 5th gear cover via five 11mm bolts.
5.   Remove clutch fork and throw-out baring
6.   Remove trans inner bell housing case  bolts:
7.   Remove 4 sychro shaft nuts on bell housing side of trans: 

8.   Place trans upright and remove remaining case bolts.  You should have something that looks like this: 

9.   Remove main gear selector shaft via 2 bolts on side of trans: 

10.   Next to that, there are two gear selector linkage retainers held by T45 6-point torque star bolts.  Remove the retainers: 
 

11.   On the opposite side of trans, there are the same two retainers, remove them.  Also remove the “VW” emblem gear selector shaft holder via two bolts.  ALSO remove the smaller 6-point TS bolt that is in between the two retainers: 

12.   Remove the 5th gear selector linkage via two 12-point TS bolts: 

13.   Remove gear selector that you just took the linkage off of as follows:  Remove round wire spring from top.  Push down on the selector to lock it in 5th gear, then pull up with some oomph.  Be careful and pay close attention to how this assembly is because when you take this off, the 3 small rectangle things between the selector and the gear will probably go everywhere.  It will be up to you the put this stuff back together!  You may want to take a lot of pictures to help you remember how it all goes back together.

14.   Remove the T60 6-point TS bolt and washer that holds the gear for the selector you just removed.  You probably have to use an impact gun to take it off because the shaft will spin. (Note: if you keep the selector on and put it in gear, you may be able to take this off with a ratchet, not sure though).  Now use a gear puller to take this gear off.  You may want to use a torch to heat the gear only and loosen it up, but I did not need to.

15.   Do the same with the other gear that is next to it on the other shaft.  I had to modify a puller to get it to fit right; I had to grind sides of the puller to make it thiner: 

16.   Looking down at the top of the 5th gear housing, there is a 6-pont TS bolt in a recess of the case.  Locate and remove this bolt.  Sorry no picture.

17.   Remove the top half of the case.  You should now have something that looks like this plus the main gear selector linkage: 

18.   Remove main gear selector linkage and reverse selector linkage and gears via one 6-pont TS bolt.  Be careful and pay close attention to how all this will go back together!  The gears and everything that needs to come off should just slide off.  There will be some exposed needle bearings so be careful not to disturb any of these: 

19.   As a unit, remove both shafts together and lay them aside: 

20.   Take a break and drink water.
 

21.   Simply pick up stock diff and ring gear(a.k.a. final drive) assemble out of case: 

22.   Use a drill press and drill out factory rivets that hold the ring gear on the diff (and say hi to my dads’ belly): 

23.   Thoroughly clean ring gear of all metal shavings using parts washer and/or compressed air.  Be careful of your eyes people.

24.   Put ring gear in a toaster oven or something other than a microwave and heat ring gear to at least 150ºF.  You may need to heat higher than this.

25.   While your ring gear is cooking, install the Peloquin bolt kit on the Peloquin Diff.  The
Peloquin instructions say to use a hammer and the nuts to pull the stud through.  I ended up over torquing the crap out of the nuts and had to get a new bolt kit ($50 from ECS tuning).  I have the luxury of a 20 ton press and used this to push the studs through the second time around.  Make sure you’re installing the studs facing the right way.  You may need to put the ring gear around the diff before you install to bolt kit.

26.   Put heated ring gear around diff making sure it’s all the way on and the right way.  Be careful, it’s hot.  Finish installing bolt kit with plates.  Make sure studs are properly seated and nuts have been torqued a few times, 52 Ft-lbs.  Read all Peloquin instructions regarding this, it only takes 30 secs to read the lack of instructions they give you.

27.   Remove all stock parts that are on the drive flanges (brass parts and spring): 

28.   Replace o-rings on main gear selector linkage retainers(4 big o-rings) and the four shaft studs(4 small o-rings) with o-rings supplied by Peloquin. 

29.   Replace races for diff bearings in the case with the new races supplied.  I did not do this; I just kept the old races that were already installed in the case.  They were in good condition and my trans only has 55,000 miles on it.  This may have been a mistake but you can decide.

30.   Place diff/ring gear assembly back into case and put everything back together.  Use a small amount of Ultra Grey RTV to seal the case and other parts (gear selector shaft plats, etc). I guessed on a lot of torque specs, but I did torque every nut and bolt.  I put most everything at 25-35 NM.  The small bolts that hold the 5th gear cover required much less, I think around 10 or 15 NM.  Be sure to use the new supplied gasket with that cover as well, but do not use RTV on this rubber gasket.  The trickiest thing about the reassembly is the 5th gear stuff at the top.  The little rectangle things go in the smaller gaps in the selector.  You may need to heat some of these gears in the toaster oven to help you push them on.  I did for the bigger 5th gear.  Exercise extreme caution when using the bolt and washer to push this gear on, you do not want to strip these fine treads.  Once everything is back together and tight, fill the trans with two quarts of 75W-90 synthetic gear oil and grease clutch fork and throw out bearing stuff.  Always use a new throw out bearing (not supplied).  It’s a good idea to install a better clutch and maybe a light weight flywheel if you want while you have everything out.  Stronger gears or a sixth gear would not be a bad idea either, but that’s a whole other can of worms.  Put the tranny back in and enjoy your new found traction!!


If you want a Word doc with pics that go with the install, post or send me your e-mail and I'll get it to you.  Thanks.

[Bastard]

new found traction.. LOL

the diff helped a LITTLE bit off the line, and more in the corners.

but the amount of traction available in a markIV chassis with street tires, even aggressive ones, is appaling.

[piotrek]

good info 

[GTIguy20v]

Thanks.  I had a good version in a word doc with pictures that went with a lot of the steps but I can't figure out how to post all that.  I also posted on gtiowner.com and tried to attach it to a post but the file was too big.  As I said in my first post, if anyone wants this good version, I can e-mail it to you.

[enginerd]

Good post, but there is some pretty significant mis information regarding the diff bearings.
 
The OEM diff, and the Peloquin diff will have a slightly different overall lengths when assembled and with the bearings pressed on. This is due to manufacturing tolerances in the diff, the bearing and the bearing races. This is diferent from transmission to transmission diff to diff. To have the appropriate bearing preload the races are pressed into the transmission housing with a thin metal shim/washer under the bearing race. These shims are available from the factory in various thicknesses. The proper method is to install the bearing races without any shims and bolt together the transmission with the new diff you dont have to use all the bolts, but you should use the ones around the diff case.  Then using a dial indicator you check the play in the differential. based on the play you select a shim to give the proper preload on the bearings. You dissassemble the tranny remove the bearing races using a punch or special puller, and install the shim and seassemble the whole thing.

Failure to do this can cause excessive bearing preload which can cause premature bearing failure, noise (especially when cold),  or you can have a lack of preload which can cause bearing failure, noise, uneven tooth loads, gear failure, cup seal failure etc.

At the very least you should have checked the preload with reusing the old bearings. Would I pull it apart to check it no, but if you have any tranny noise now or in the future that would be a highly suspect thing to check. You can actually check the play with it still in the car but you need to drain it.

 

[GTIguy20v]

Thanks!  But how do I check the play?  Where do I measure?

[enginerd]

you pull one of the driveshaft flanges, and measure the play on the differential body. There is a nice flat surface inside there, you can rotate the diff and push one way then rotate and pull the other way and check the movement.

[WilliamB]

Hey, nice writeup; I've got a quaife lsd looking to get installed; appreciate it much if you'd send me the writeup with pics. Thx, Will

[turbowolf]

but the amount of traction available in a markIV chassis with street tires, even aggressive ones, is appaling.

I agree, not to mention front wheel drive! 

[inivid]

nice writeup