I'm in the process of attempting my first rebuild or "freshening" of the diff in my SE. Currently, breakaway torque checked at one wheel off the ground is ~15 ft/lbs, and it definately isn't working properly. I'm still driving the car whilst I attempt the rebuild on another complete rear from a SE parts car. So far I took the whole rear out, pulled both axles, removed the ?drive pinion housing? and pulled the diff gear assembly out of that. I've a printed out copy of FSM and have been looking through it so most questions are with the FSM's instructions in mind, now on with the questions: 1. Do I need to mess with the drive pinion, flange removal, then upon re-assembly adjusting pinion, and pinion height? (If there is no suspected problem there) 2. Is the only way to get the backing plates off to grind the axle bearings off? 3. Do you have to use new axle bearings? 4. Is there any way to check breakaway torque without completing re-assembling everything?
My fear is that I might have to take it back apart to get everything just right at least once or twice, so could I do so and then get new axle bearings put on? What ,if anything ,absolutely has to be new upon re-assembly? Any help from those that have done it is appreciated, after reading through the FSM, I feel overwhelmed...

 

A couple of threads in the archive:
LSD rebuild
Differential assembly

The pinion height procedure isn't necessary if you're reusing the same ring+pinion and differential carrier. The whole point of that is to find the correct spacer under the rear pinion bearing.

The bearings are pressed on over the backing plate, so yes, they would have to come off first. If the bearings have been making bad noises, might as well replace them. If not, they can last a good long while.

 

The pinion will be going back to the case and diff it parted from, so I hope I don't need to do anything with it. I reread those threads...That guy says you can't increase your breakaway torque in the SE diff because of the way the disks in the stack are assembled or how many drive disks they have or whatever...That upsets me.

 

you can flip the SE, so its built like a 12A THEN you can make it tighter.

 

...Please continue! What are my best options with what I have...I have the 1.one SE rear and diff allready apart,2. another entire SE rear I can take out of another parts car if necessary, 3.AND a possible LSD diff ('81-"83)I recently kept from a rear end I scrapped from many moons ago. It came out of an '81 frankenstien I used to have...Definately the small axle one. I kept only the diff gear assembly, not the bearing outer races, adj. screws, bearing caps, etc.(Guess I was thinking ahead and of the possible oversized disks it might have compared to my SE's)?
What's my best plan, and are there any bearings I should replace for the hell of it?(if they're cheap)? The diff. I'm rebuilding came from a SE that sat in a field since '91(purchased in '06) with ~136,000 miles on it and of course, I could never start it and drive it to assess the cond. of it's rear...

 

one of the other threads had pics, but the 12A is like friction plate, plate, friction plate, plate, friction plate, plate, friction plate, plate.

on the GSL-SE they wanted the LSD looser, so they flipped a friction plate and a plate. so you can just go in an flip them back around.

2. no factory assembled diff will have oversize plates, you have to buy those, they arent expensive.

@130k the bearings should be good unless they are rusty or something

 

No, bearings aren't rusty or anything, but I have concerns about the two you have to pull to get to the "stack" and then press back on. I was(for some reason) thinking the 12A diff plates were thicker(individually) than the ones in a SE diff. If I do go about making a stack like the 12A's and not the SE's, what specs would I follow for assembly? Still the specs for the overall width of the stack or whatever per SE instructions?

 

I don't know what j9fd3s means by "flipping them around", but the first post in the LSD rebuild thread tells the difference.

There are discs with tabs on the inside and discs with tabs on the outside. The GSL has 2 of each on both sides, while the GSL-SE has 3 of the discs with outside tabs and 1 of the inside tab discs on each side. So you're looking for at leas 2 more discs with inside tabs to substitute one of the outside tab discs on each side. You can get slightly thicker ones.

In my 1984 FSM I didn't see any different specs for GSL or GSL-SE, so I'm assuming the limits are the same.

Do you mean the carrier bearings? You don't have to pull those to disassemble the LSD. It's a good idea to not mix up the races though, or the blocks that hold them to the diff carrier.

 

Thanks for the reply. The bearings I had in mind are called side bearings by the FSM(9-15) and their removal is the first step to disassemble the diff. assembly according to FSM. You are right that the FSM makes no mention of alternative assembly for SE diff stack...

 

Can anyone tell me EXACTLY what bearing(p/n) I need to get from NAPA for the side bearings? I have the diff assembly out and took it to the local dealer...Waited for 20 minutes to have some a-hole tell me he'd pull my bearings off with their bearing puller for 70 dollars...Then refused to give me a p/n for said bearings unless I paid for them up front. God, I hate the a-holes there...The removal of those bearings is what's keeping me from continuing.

 

The bearings don't have to come off to split the differential carrier. You can also get the parts to do a full rebuild on a rear diff from black dragon for cheaper than NAPA

 

Thanks for the input...I'll check out BlkDragon. I can't get the damn things off, I got a round slug made from 3/16 steel for the bearling puller to push against, and it's as tight as I can get it by myself, and the plate is bending in the middle! It never even budged! I know these bearings have at least 130k miles on them, and thought I'd just replace them anyway. I didn't know the left and right halves will seperate without removing these bearings...(see attached fsm pic)

 

It's the ring gear bolts that hold them together.

 

Thanks again, good to know, at least I can finally get inside the damn thing and see what I got to work with and what needs replaced...Still need to figure out how to remove the bearings, though.

 

I think you need a press with a bearing separator and a piece of rod/pipe that can fit within the the bearing's inner diameter.

 

yeah it needs a hydraulic press

 

I cit the bearing cage off then use a small carbide bit to grind as far through the bearing race as possible being extremely careful to not go all the way through then, take a chisel and give it a whack to crack the race. It will then slide off. Not exactly the correct way of doing it but without a press capable of doing it correctly it works good.

 

As already stated, the way I get those bearings off, is I cut the outer race off and slit the inner race and wack it with a chisel in that slit. It deforms and spreads the race enough to get it off.

There is another option for a tighter rear.

since you have an se and your tearing it all the way down, you can use the Torsen diff out of a 95-97 Miata. If you want a better ratio, you can use the front ring and pinion out of a '97+ kia sportage 4x4.

What is absolutely necessary to replace is the pinion crush sleeve.

I've done this before and a word of caution, if you don't get it right, you will be needing your spare rear ends! I don't mess with this work anymore. I got my axle fully rebuilt from a local place here for less than $300 (all new bearings, seals, labor and warranty)

 

OK, I finally got inside the damn thing today...Apparently the digital calipers I bought at Har.Frei. are CRAP because all my disks measure thicker than new, and when you close them(calipers), it's never zero again, and never the same value twice. Everything inside the rear I took apart looks brand new and I double check the OD. on the car it came from and it shows only 112k miles.
1:What's the proper way to measure the thickness of the conical springs? Just at the outer edge, or the whole thing?
I'v been referencing the fsm and steve84GS_TII's threads.
2:What's the best way to measure the width of the lsd unit with all the disks installed to determine clearance inside the lsd case? I mean, how do you hold it tightly and take measurements when everything's just sliding around everywhere?
3:Why does he(steve84...) recomend for the ideal, aggressive lsd (big axle)to use the plates and carrier from a 12a car and then only the spider core from SE? Can't I just assemble the disks like in a 12a car, but use ALL se parts?
What I mean in "3:" is: speaking from outer(con. spring) to inner(pressure ring) the stock SE is assembled; friction plate-friction plate-friction disk-friction plate. the non SE is assembled; friction plate-friction disk-friction plate-friction disk.
Can't I just get two more friction disks, lose two of the original friction plates,and assemble them the non SE way? I'm still a little overwhelmed and trying to learn, and help is appreciated.

 

I don't know if you still need them, but I've got a set of brand new bearings, (side bearings and pinion bearing) that I bought when i was having my R&P switched to 4.44's, but my bearings were in perfect shape so I didn't use them. $25 shipped and they're yours.

 

Yeah, I might as well take them...For the big axle size, correct? pm me for payment and shipping details. THanks.

 

Anyone able to help me out? Steve...?

 

Anyone?

 

The middle, use a micrometer.
Instead of tight just hold it steady, making sure the disks don't slide or wobble when you tighten up the micrometer.
He's doing what you're planning on. In that thread he uses the driven disks from the 12A because his GSL-SE ones have the inner tabs worn off.

 

Thanks for the reply, I appreciate the help. I guess I'll have to somehow get another person to help "hold" my stack whilst I measure...After I get a new, accurate set of calipers. As far as using a micrometer for the conical springs, you mean the type shaped like a "C-clamp", correct? Not the sliding style of micrometer I'll be using to measure the stack? Also, as far as measuring the stack, how clean should everything be? I mean, do I need to "scrub" all the stuff out of the disk "grooves", and Th.Washer "holes"?