Comments on: Gavins DIY Gurumotorsports Differential install(Huge)(lots of pics) - Page 6

**gavin** · 6-18-07, 17:47

and that is actually.....really helpful

It doesnt matter to me at the moment as I was able to get some factory shims for the reshim of the diff, but is anyone else is brave enough(or stupid enough) to do this...the info is there(provided that ford actually still has the parts).

Gavin

**SixSick6** · 6-20-07, 17:22

Gavin- I had been watching this for a while now and logged ina little too late:
eBay Motors: 1988 Ford Probe Rotunda Tool Kit T88C-7000-S (item 220121709906 end time Jun-20-07 14:20:53 PDT)

$27.

I confirmed the part numbers when the auction started through my Ford manuals. It was/is a combination of MTX and ATX SST's along with a few other goodies thrown in as well.

**compnut21** · 9-25-08, 19:51

thanks for the update gavin.

**gavin** · 9-25-08, 19:55

No problem.

Id forgotten that I did in fact have an addendum to shimming the diff, but it was a bit buried in here. Figured it was worth it to add it to the main post.

Gavin

**jesiotrot** · 9-29-08, 8:51

I meant to add this in here when i first figured it out, but that was 9 months ago and i guess i forgot till now! Lucky you guys bumped it to remind me.

Quote:

It seems that mazda has speced an odd sized bearing to use to suspend the diff (75mm OD, 45mm ID and 21mm thick)

The bearing size is actually 75mm OD, 45mm ID and 20mm thick.

I read your guide Gavin, and went and bought the right bearings. But, after seeing they needed to be 21mm thick, i added a 1mm shim underneath each bearing. Only to reassemble the gearbox, and find the case would not close. It had a 2mm gap. Destroyed the bearings pulling them back off the diff, so a new set later and they went in perfect!

The bearings I got are Koyo brand, made in Japan. And i just got them from a bearing wholesaler. Part no. is 32009JRYA1

On the off chance that anyone else uses this guide, you may want to update it!

**gavin** · 9-29-08, 20:15

Quote:

Originally Posted by jesiotrot

The bearing size is actually 75mm OD, 45mm ID and 20mm thick.

This is absolutely correct.

I just checked the old diff and bearings and saw my error. The diff bearings are roller bearings. They have two conical races sandwiching the bearings and bearing cage. The bearing cage actually extends ~1mm above the measured bearing surfaces. I mistakenly added that extra height to the total thickness of the bearing.

Changing the post.

Gavin

**jesiotrot** · 9-30-08, 4:13

Good to hear! Hope nobody else got caught out by this. Though I doubt anyone did, to quote you Gavin -

Quote:

Originally Posted by gavin

Wow, someone actually had a use for the writeup? Color me shocked.

Damn straight i did! There is no way i would have attempted dismantling the gearbox without this guide!

And if anyone is interested. I have done about 10,000kms on the guru without issue. I drive the car every single day, my sister drives the car sometimes and cant even tell its different than before. So normal driving they just feel like a stock diff. Traction in light rain is improved, and cornering in the wet feels much better.

**SABBAi** · 9-30-08, 8:58

And second gear static burnouts are a cinch

**Wibla** · 10-6-08, 18:28

Silly question, probably answered already; are these available anymore?

**gavin** · 10-6-08, 18:46

Unfortunately no. Guru motorsports did two production runs of the diff with the stipulation that there would be buyers for the items when the diffs were done. Guru still has the plans and the jigs for a possible 3rd production run, but there has to be a minimum of 10(or was it 15?) buyers at the ready. The last time this was attempted there werent enough people to make it happen.

Gavin

9-25-08, 19:51	#78 (permalink)
compnut21 words under name Join Date: Oct 2007 Location: Olympia, WA iTrader: (7)	thanks for the update gavin.
	89 GT 4WS/Megasquirt/FE3 Needs blinker fluid. My FE3T Project 89 GT Partout!

9-30-08, 8:58	#83 (permalink)
SABBAi Join Date: Apr 2004 Location: Melbourne, Australia iTrader: (1)	And second gear static burnouts are a cinch
	Teh Telstar can NEVAH lose!

10-6-08, 18:28	#84 (permalink)
Wibla 4ws newbie Join Date: May 2007 Location: Telemark, Norway Age: 24 iTrader: (0)	Silly question, probably answered already; are these available anymore?
	'88 Mazda 626 2.0i-16 4ws

6-18-07, 17:47	#76 (permalink)
gavin Join Date: Jan 2001 Location: santa cruz.ca iTrader: (1)	and that is actually.....really helpful It doesnt matter to me at the moment as I was able to get some factory shims for the reshim of the diff, but is anyone else is brave enough(or stupid enough) to do this...the info is there(provided that ford actually still has the parts). Gavin

6-20-07, 17:22	#77 (permalink)
SixSick6 Join Date: Sep 2001 Location: San Diego, CA, USA Age: 32 iTrader: (2)	Gavin- I had been watching this for a while now and logged ina little too late: eBay Motors: 1988 Ford Probe Rotunda Tool Kit T88C-7000-S (item 220121709906 end time Jun-20-07 14:20:53 PDT) $27. I confirmed the part numbers when the auction started through my Ford manuals. It was/is a combination of MTX and ATX SST's along with a few other goodies thrown in as well.

9-25-08, 19:55	#79 (permalink)
gavin Join Date: Jan 2001 Location: santa cruz.ca iTrader: (1)	No problem. Id forgotten that I did in fact have an addendum to shimming the diff, but it was a bit buried in here. Figured it was worth it to add it to the main post. Gavin

10-6-08, 18:46	#85 (permalink)
gavin Join Date: Jan 2001 Location: santa cruz.ca iTrader: (1)	Unfortunately no. Guru motorsports did two production runs of the diff with the stipulation that there would be buyers for the items when the diffs were done. Guru still has the plans and the jigs for a possible 3rd production run, but there has to be a minimum of 10(or was it 15?) buyers at the ready. The last time this was attempted there werent enough people to make it happen. Gavin