Rebuild kit for rear diff

Cp2295

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Aug 8, 2016
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Hi everyone im having trouble sourcing a rebuild kit for this posi diff i picked up a couple weeks ago. Thought it was a toyota 7.8" but was mistaken when the rebuild kit that showed up had all the wrong bearings (too small). Its from a mk3 with an lsd and 3.91s (counted the teeth). Anyone know where to get one for a good price? Diff was missing carrier shims and the pinion bearings although not horrible should be replaced, i would prefer to just replace all of it though and be done with it lol.


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Piratetip

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There is no rebuild kit that has the right bearings.
Usually Yukon or Nitro gears will put one together for most of the vehicles out there.
They never did for the 87-92 Supra, and if you find one that is labeled as such, it will be wrong as you have found.

Buy the bearings/seals/pinion nut/carrier shims(after you calculate what is needed), ect.. separately from Toyota and make the kit yourself.
That's what I do for every diff rebuild I have performed.
All the correct PN's are easily found on the EPC in cygnusx1 or if you have an offline EPC program.

Driftmotion is selling all of these parts together as a "kit" for the apathetic customer, but it won't be saving you any money.
 

Cp2295

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Okay, thanks for the info man. Are you or is anyone aware whether or not toyota pickup carrier shims would work? I see no reason why id need to re shim the pinion since i am not changing gears. I figure itd be easier if i could get a set of shims since all i got is a micrometer which is pretty inaccurate lol, i usually get it close and check it with a dial indicator and some marking compound. Also, will a pickup crush sleeve work?


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Asterix

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I recommend to just buy the Driftmotion rebuild kit, containing all bearings, shims, and seals. It's way easier than trying to get all the parts from Toyota. The big pinion bearing was very hard for me to get when I did mine 2 years ago. No, it's not really cheaper, but it's way easier.

You'll also want a solid pinion spacer to replace the crush sleeve. Search for forums for where to get that. I also bought a shim kit from McMaster, which came in very handy, as the solid spacer kit didn't come with the enough shims for me.
 

Piratetip

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Cp2295;2094361 said:
Okay, thanks for the info man. Are you or is anyone aware whether or not toyota pickup carrier shims would work? I see no reason why id need to re shim the pinion since i am not changing gears. I figure itd be easier if i could get a set of shims since all i got is a micrometer which is pretty inaccurate lol, i usually get it close and check it with a dial indicator and some marking compound. Also, will a pickup crush sleeve work?


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Toyota pickup rear diffs don't use carrier shims like ours do, they have adjuster wheels for the backlash and carrier preload.
There is a table of 31 different thickness shims for our vehicles, you have to calculate which one you need during the diff setup.
They are about ~$5 each so it can become expensive when you aren't calculating them right.
http://www.cygnusx1.net/Supra/Library/EPC/291410/part.aspx?S=41334C
The rebuild procedure is all there in the TSRM.

Over time I have amassed a collection of about 20 different thickness shims for the carrier, but there are still some setups where I don't have the exact shim I need.
I still need to purchase them from Toyota occasionally.

Toyota V6 rear ends will have the same crush sleeve, pinion bearings and pinion depth shims, but their carrier bearings are not the same.

FYI if you aren't changing gearing, your pinion depth should still be spot on.
You should not have to set that with extra shims.

Parts are still easily sourced from Toyota, I order a set of diff parts every 3 weeks or so.
 
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Cp2295

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Okay appreciate the info man. So there arent any other shims from another rig that would work then huh? Maybe i might be able to get my open diffs shims to work-crapshoot but worth a shot


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Piratetip

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What do you mean? The carrier shims?
Open diff or LSD, it does not matter they both use the same style shims.

There are only 2 models I am aware of that use the same style carrier shims:

- Cressida 1989-1992 GLX 6 Cyl 3.0L 7MGE; MX83
- Supra 1986-1992 6 Cyl 3.0L 7MGE, 7MGTE; MA70