I've done some searching and could not come up with this particular type of differential anywhere. I do know it is a planetary type, not spider gear. If anyone on this forum knows what I've got here, your input is much appreciated.

On a slightly different note; While checking the side clearance with that same diff I keep seeing a TOTAL clearance (no shim installed) of about .450mm. To double check my numbers I rechecked that the bearings were in fact seated fully on the diff: OK. I got the outter races good 'n lubed and also made sure the diff was fully seated in the clutch housing. And yes, I did have the Tranny Housing Bolts torqued. The bearing seat is completely clean as well.

Anyone experienced this before?





Thanks

 

Bedtime refresh; Calling all Transmission Masters.

Your comments are much appreciated!

 

Kind of looks like the OEM Y21/S4C JDM LSD. Optional in 92-00 B16A's.

 

Ah... thank you,

Well now I suppose I should go pull out my Trans Shafts and crunch some numbers. This diff came out of a supposed JDM GSR trans that I've never bothered to check out. Ever since buying the car I knew I'd have to rebuild the whole thing anyway, so the fact that my RPMs for any given speed were almost identical to my friends USDM GSR was good enough for me.

Now I have a few more questions.

Is there a planetary gear driven LSD?

Does anyone have the correct torque spec for this bolt pattern?

Any reason why this particular diff does not have reverse threads?

And what to do about that side clearance...

Thanks again for the help

 

Only reason that led me to believe that its an OEM b16 LSD; its because of the weird 14 or w/e bolt ring gear.

 

Which bearings did you use?

wider GSR or narrow LS?

one is 18mm wide at inner race, other is 19.5mm wide.

 

The pictures on top are current with the bearings I ordered and installed.

91005-P80-E31
40X80X18/19.5

Directly off the parts listing page. Most likely the 19.5 (00 Type-R)

I always believed that most of the GSR bearings were tapered roller and the LS/Type-R used the shielded ball bearing (exception being newer GSRs that use BB?) The LS having the 18mm and Type-R using the 19.5.

So if I were to use or switched to the 18mm wouldnt the required shim thinkness be 3.5mm(out of range)? Using the rough number I've come up with already.

haha, I'll let you do some speculation on it as I'm sure you probably have the answer on your finger tips.

Thanks for the help

 

Asumming your numbers are correct.

You could use shims on BOTH sides of the diff (keep it centered) or use one 19.5mm and one 18mm diff bearing and shim from there. You can run "wide" on larger clearances on the normal bearings without issue.

Waiting on a B GSR + OBX I built to report in. Pulled a 19.5mm diff bearing off and used a 18mm D/LS diff bearing to correct.

Shimmed out correctly, VSS was centered, need to hear the 500 whp report.

It started out as a what was thought GSR trany getting and OBX, turned out it was a B16 when the ring gear didn't fit.

 

Hope he can hold his foot still with the B16 instead. Gotta love backtracking surprises.

Ha assuming is correct. Not a whole lot of flat space to run a gauge in there, but i've settled between .016/.018. How wide to you prefer to run? After pushing on a new bearing I'll check it again. I'll definately replace the transhous side only to keep the vss centered (how would you check for equality?).

If I were to replace both with 18mm what would I shim with on the C.H. side? Aside from being ignorant I dont recall seeing a machined slot for a shim on that side, prove me wrong then I've answered my own question.

While I have your knowledge at hand would you mind answering another quick question.

If just replacing all shaft bearings do you still recommend reshimming the M.S.?(for stock b18c1)

Much appreciation for the advice.

 

You can run shims on both sides.

needed 2.7mm total shimming, went 1.3mm on both sides.

Stock clearnace is .000-.004", on the early OBX's I ran as big as .025" before the B16 Oil ring trick was known.

Just replacing the bearings on the MS, shouldn't have to reshim, but still need to check. I have a little shortcut that has worked ok so far. I prefer about .010" preload on the thrust washer by the ISB. This means .010" feeler gauge when the cases are pressed togther with only the MS installed.

It's a feely thing, hard to explain.

 

B16 Oil Ring trick hey? New to me. 81mm bore 80mm shim, Ha I am just missing something obvious.

Now about this shortcut that just sounds less expensive and time consuming. How are you using a feeler gauge with the cases torqued to check the preload? Cant quite visualize that despite my best efforts.

Thanks again

 

where did I say I torqued thje case before checking preload?

81mm oil ring, snap off 1/4" lngth = .5mm diff shim.

My student I doubt will help much, your gonna have to figure it out yourself

Teaching 101, include PICS!

 

Well that being said do you recognize the diff in the pictures above?

[QUOTE] I prefer about .010" preload on the thrust washer by the ISB. This means .010" feeler gauge when the cases are pressed togther with only the MS installed.[QUOTE]

When you said pressed together I assumed that meant torqued to running spec. But now it's kinda coming to me. Install M.S. with thrust washer and shim, drop case on top averaging the gap between the T.H. and C.H. shooting for about .01 of "gap" which is also the applied preload when torqued?
I dont assumed myself correct because there is the weight of the casing (and loaded M.S. depending on orientation) to consider not to mention inconsistencies of the housings themselves when your talking .010. dangit.
This is me raising my hand, please.


Suppose i could convince a friend he needs some new rings....

 

Ha said friend says maybe after 100,000 on his '00 Si.

Has anyone else found a nice shortcut for checking the preload on the MS thrust washer?

I'm hoping Mr. Bones will pipe in for me again and elaborate a little on his own method.

New bearing and a bit-o-shims should arrive early this week.