Supra Diff replacement part #s

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timxr8
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Supra Diff replacement part #s

Post by timxr8 » Fri Sep 27, 2019 10:04 pm

To keep this from getting lost in the facebook cyberspace (I hate searching there), I decided to post this here and then people can link there or hopefully search here before posting on social media.

Here's a list of the replacement bearings and seals for the Supra Diff. Quick recommendation on these, as I've freshened/upgraded 4 of them with no issues. I always do 2 things minimum: Weir performance upgrade kit and a solid pinion spacer. I've gotten to the point of doing the pinion spacer by feel, which is actually quite easy.

The other things I do that do not require any sort of expertise in setting up a differential (only if working with a known good diff) are the front pinion bearing (no change in pinion depth) and all of the seals. The other bearings on the diff are gigantic. The rear pinion bearing is over 3.5" dia. and the carrier bearings are 83mm dia. I've only had 1 where the front seal let some water in and pitting occurred.

Without further delay, here's the P/Ns. All Timken except the Carrier:
Pinion Seal: 1177 (Rockland has a nicer one with a 3rd lip. OE does not have this. Not real necessary, but nice.)
Front Pinion Bearing: 30306M
Rear Pinion Bearing: 35028
Axle Seals: 710142
Carrier Bearings: Nachi 50BK8301

Hopefully helps out some people.
Tim Spencer
1988 XR4Ti Duratec project car
2011 Taurus SHO daily driver...not stock.

my8950
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Re: Supra Diff replacement part #s

Post by my8950 » Sun Sep 29, 2019 8:14 pm

Yes, it does help.

Need to figure out drive shaft as well, even though every car has somewhat of a different configuration.

Thanks for posting!

timxr8
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Re: Supra Diff replacement part #s

Post by timxr8 » Sun Sep 29, 2019 9:45 pm

my8950 wrote:
Sun Sep 29, 2019 8:14 pm
Yes, it does help.

Need to figure out drive shaft as well, even though every car has somewhat of a different configuration.

Thanks for posting!
I've got some part #s for making a larger 2-pc shaft with the stock CSB. I don't know if everything clears, but the bore is the same as our bearings. 2.5" or 3" steel front 1310 U-Jointed driveshaft. Makes it easy to run an aluminum rear section. A few 4x4 places have adapter joints to go from the Toyota to a 1310. Just a thought.
Tim Spencer
1988 XR4Ti Duratec project car
2011 Taurus SHO daily driver...not stock.

trueblue1968
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Re: Supra Diff replacement part #s

Post by trueblue1968 » Wed Oct 09, 2019 2:16 pm

Drive shaft flange, and Solid crush sleeve options "Marlin Rock Crawlers"
TOO MUCH IS NEVER ENOUGH!........
....More to come :twisted:

timxr8
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Re: Supra Diff replacement part #s

Post by timxr8 » Sun Oct 20, 2019 2:28 pm

trueblue1968 wrote:
Wed Oct 09, 2019 2:16 pm
Drive shaft flange, and Solid crush sleeve options "Marlin Rock Crawlers"
"solid crush sleeve" = Solid pinion spacer

Quick disclaimer on the front pinion bearing: the one I recently received was the correct 30306M, but the depth seemed off. Everything went in correctly, but the bearing contact angle is entirely different from the OE unit. THe cup and cone matched, but the OE bearing was very different. This created ~3mm difference in depth. Doesn't sound like a big deal until getting the pinoin flange on and realizing the dust cover is contacting the maincase. Luckily, the amount of pinoin spacer shims I had lying around allowed me to space it out. Measured runout on the flange face to about .004", which is good enough. I realized most of the time I get the Koyo bearings, and simply found the Timken one cheap this time around.
Tim Spencer
1988 XR4Ti Duratec project car
2011 Taurus SHO daily driver...not stock.

Turbo
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Re: Supra Diff replacement part #s

Post by Turbo » Fri Oct 25, 2019 8:18 pm

Thanks... now to figure out how to get it mounted.
'86 Merkur
'96 Impala SS
'05 SRT-4
'08 Hemi Ram

dunhamr1
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Re: Supra Diff replacement part #s

Post by dunhamr1 » Wed Nov 13, 2019 9:36 am

Turbo wrote:
Fri Oct 25, 2019 8:18 pm
Thanks... now to figure out how to get it mounted.
Same... I have CAD files for a weld-in solution from a friends rally car since JVAB is looking to have something like ~30 people to be ready with cash for another run. Obviously don't take the plans and sell it as a kit (or at least talk to the guy who created it first), but I can send you the files.
-Ryan Dunham
1989 Merkur XR4Ti - nickname: "SheaXR4"
Daily: 2016 VW Golf R "Matti"
E-Street Autocross car: 2001 Mazda Miata
Old daily: 2003 VW Golf MkIV TDI, 200k+ mi

"Racing is Life. Anything else is just waiting." -Steve McQueen

Turbo
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Re: Supra Diff replacement part #s

Post by Turbo » Tue Nov 19, 2019 8:55 pm

dunhamr1 wrote:
Wed Nov 13, 2019 9:36 am
Same... I have CAD files for a weld-in solution from a friends rally car since JVAB is looking to have something like ~30 people to be ready with cash for another run. Obviously don't take the plans and sell it as a kit (or at least talk to the guy who created it first), but I can send you the files.
That would have been awesome... but too late, I tried waiting on JVAB - been on list over a year, figured he didn't want to make anymore, I ended up going MK route.
'86 Merkur
'96 Impala SS
'05 SRT-4
'08 Hemi Ram

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