Solid pinion spacer question

[5uprahboy]

Hey all

I'm rebuilding my MK3 diff, well, replacing the bearings and seals, and I've just ordered a solid pinion spacer from Weir Performance.

My question is - how do you work out what shims to use? Surely you don't have to assemble everything to check clearances, only to find that you don't have enough, or too much, and need to take the pinion out to change shims? Which would mean pressing the inner race off the front of the pinion every time? Isn't this bad for the bearing?

Cheers

Hunt

 

[nathaninwa]

You said it right. The setup needs torqued (without seal) and pinion preload set. Pulling it apart each time to get the spacers correct. And once your close, a .001 change is a lot. To overcome the bearing problem, you diegrind the inner race of the old one just enough so it will slip on/off. Then install the real bearing when you all set. You could measure the old crush sleeve to get you close, but I bet it moved onced the tension was released.

 

[Poodles]

It's not really an issue. Also, using the old bearing won't work...

http://www.supraforums.com/forum/sh...o-A-few-tricks-to-beef-up-the-rearend-carrier

 

[nathaninwa]

Unless the old bearing was growling and flat out worn, he should be ok. Ive done about 6 myself and helped with about dozen other solid spacer setups and all have been within 1in/lb after the new bearing install. For testing we would install the seal to see what overall tension was, then install the bearing. This incredibly helpful if your doing the rearend in the car. Just stay in the middle of the range.

 

[5uprahboy]

Thanks for the replies.

From what I can gather the bearings were over torqued as the front pinion nut was SUPER tight.

I wont be using the old bearings. Will be using new ones.

Was thinking of measuring the existing crush washer's length and using that as a base to start with the solid pinion spacer and shims.

The only issue I see with using the old bearing so it slips on and off without too much issue - is if the bearing rollers themselves have worn - then when I put the new one in, it might be a bit 'tight'?

Cheers

 

[nathaninwa]

It may not have been overtorqued, them nuts are tight to keep the preload for 200, 300 thousand miles. With the crush washer it takes like 300ft/lbs to initiate the crush, and depending on thread, youll be torqueing the new nut pretty tight too, probably with some locktite.

I can totally see the argument of the bearing worn, but generally if its not blue from overheating and no beat to death its rather pretty close.

If your concerned with the front pinion bearing, then you need to check backlash, pinion depth from the new rear bearing and carrier preload too with new side bearings depending on how its tensioned.

 

[5uprahboy]

Does anyone know what the 2 front bearings I need are numbered as? I can't see the numbers on the inner races that are still in the housing and I don't want to take them out just yet.

I've had a search around but can't find the numbers anywhere on the interwebs...

 

[Piratetip]

Outer Pinion
Toyota part # 90366-30025 superceded by 9036630067 ($49.93 retail)
KOYO TR0607J-1
NSK R30-13
Timken - 30025
SKF - BR114

Inner Pinion
Toyota part # 90366-35028 superceded by 90366-35028-77 ($87.55 retail)
KOYO TR070904-1-N
Timken - 35028

 

[5uprahboy]

Thank you - perfect.

Is there any preference between KOYO or Timken or NSK?

 

[Piratetip]

Nope
All are good quality.

For wheel bearings I will only use Timken though

 

[5uprahboy]

Interesting seeing the prices on amazon and ebay. Wonder what my local bearing supplier will charge....

 

[5uprahboy]

Ever dealt with or heard about 'National' as a brand?

 

[Piratetip]

National is made by Federal Mogul

That being said I would choose NTN, SKF, Timken, Koyo, or SKF over National.

 

[5uprahboy]

Ah ok.

How did you get the model numbers for the specific companies? Timken etc....

Thinking I should probably do the side bearings at the same time...

 

[Piratetip]

When you work on cars long enough you begin developing a large database of information.

Most companies have a searchable database.
Here is the one for Timken.
http://www.showmetheparts.com/timken/

If your Roller Bearings and Races don't show any signs of abnormal wear I wouldn't bother replacing them.
Pitting/Inclusions/Spalling/Scoring/Grooving, ect....
Just use the lower preload specs as outlined in the TSRM for used bearings.

 

[Poodles]

Eh, you're in there, you might as well do a complete rebuild and save yourself the hassle of doing it again later (and rebuild the LSD as well).

Koyo is OEM for a hell of a lot of Japanese stuff. Timken used to be amazing but has dropped a bit in quality over the years.

 

[5uprahboy]

Eh, you're in there, you might as well do a complete rebuild and save yourself the hassle of doing it again later (and rebuild the LSD as well).

Koyo is OEM for a hell of a lot of Japanese stuff. Timken used to be amazing but has dropped a bit in quality over the years.

I'm not using an LSD - I have a torsen.

I'll be doing both pinion bearings and both side bearings. Plus all 3 oil seals. I've checked the wear on the pinion to crown wheel and it looks spot on. Will see if it still is good with the new bearings or if I need to re-shim it etc.

 

[5uprahboy]

Ok so I've got all 4 bearings.

My plan was this - let me know if it's not going to work....

Remove both pinion races from diff casing.
Press in both new races into diff casing.
Press new rear bearing onto pinion.
Measure old crush spacer and stack shims onto solid pinion spacer until it's the same.
Grind the inside of the old pinion bearing so it's not such a tight fit on pinion shaft.
Put flange and front nut on and do up to torque spec and measure bearing preload and backlash and tooth contact to pinion and crown.
Adjust shim size as needed.
Press on new bearing onto pinion shaft and install front seal and flange.

 

[Piratetip]

Your plan is about right.
Though I would not use the old pinion front bearing to set your preload then switch to the new one and expect it to stay the same.
Plan on disassembling the pinion at least a few times to get the preload within spec with your in/lb torque wrench.

Don't forget to special order the right carrier spacers/washers from Toyota to set your calculated preload and backlash when you put the new bearings on.

 

[5uprahboy]

But if I press the new bearing on to get the bearing preload set, if I have to adjust it I'd have to take the new bearing off without damaging it.

How would I do that? To get the old one off I used a sledgehammer...