HOW TO: Rebuild the MK3 Rear Differential.
- Thread starter TurboStreetCar
- Start date
It looks like it needs a smaller bearing to fit in the truck case.
Meaning the truck carrier is smaller then the supra one.
Meaning the truck carrier is smaller then the supra one.
Won't work.
There are people who have tried though:
http://www.pirate4x4.com/forum/toyo...nfo-needed-irs-supra-other-differentials.html
Like I mentioned before, drjones also verified the pickup carriers do not fit inside the supra housings.
There are people who have tried though:
http://www.pirate4x4.com/forum/toyo...nfo-needed-irs-supra-other-differentials.html
Like I mentioned before, drjones also verified the pickup carriers do not fit inside the supra housings.
Okay so if I can't go with that option how about getting a non turbo supra carrier and putting a locker in it, what are your thoughts on running a locker in a supra?
Is this even a good idea?
Is this even a good idea?
miekedmr;2023601 said:
Many times.
Black Cat;2023604 said:
It doesn't require a thinner bearing, it requires a thicker bearing. The supra bearings are thicker then the origional pickup bearings. Use of the supra bearing is to act as a spacer or shim because the supra carrier isn't the same width (smaller) then the pickup carrier. Using the pickup bearings on a supra carrier in a pickup case, I assume wouldn't be wide enough.
Piratetip;2023606 said:
This. Didn't even think of the axle bushings in the carrier.
I don't really see the need for a locker in a supra. The LSD provides plenty of grip. A locker is really only be beneficial on a truck where you can have a tire off the ground completely in a twisty trail.
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I just looking at the cost and function of the type of locker I have Vs a new LSD unit.
Kaaz cost is $1150 plus LSD fluid, Rebuilding the factory one doesn't look to cost to much but you still have the wear items and LSD fluid.
I like how my locker works with out any air or electronic systems to fail, just apply power through the drive shaft and it will lock every time with out fail.
Right now my supra is broken so this is all just ideas but when I was driving and trying to drift my supra I did have a few issues with the LSD not working right.
Just trying to figure out ways to have a more reliable locking action with out wear items.
Edit in how this style locker works, not my video.
[video=youtube;kL0hPEOStGk]https://www.youtube.com/watch?v=kL0hPEOStGk[/video]
Kaaz cost is $1150 plus LSD fluid, Rebuilding the factory one doesn't look to cost to much but you still have the wear items and LSD fluid.
I like how my locker works with out any air or electronic systems to fail, just apply power through the drive shaft and it will lock every time with out fail.
Right now my supra is broken so this is all just ideas but when I was driving and trying to drift my supra I did have a few issues with the LSD not working right.
Just trying to figure out ways to have a more reliable locking action with out wear items.
Edit in how this style locker works, not my video.
[video=youtube;kL0hPEOStGk]https://www.youtube.com/watch?v=kL0hPEOStGk[/video]
Yea i had one of those in my '94 pickup, It worked great. I dont see the need in a Supra. All you need is a new set of clutches. If thats not "limited" enough then get the max grip kit. As long as both your tires are on the ground i think a stock clutch type LSD is pleanty. Only exception i could see is maybe in a drift car. If all you use the car for is drifting then maybe welded spiders would be better. Thats hell on a differential.
So, I'm taking the thing apart, and it's going great until I get to removing the pinion from the case. I stuck it in my press and pumped, but it seems like it's taking way too much force. The TSRM says to use an SST to pull the outer bearing first, but I don't have a puller that will do that, so I thought it ok to just push the pinion out. Everything else has come apart fairly easily so far, though I haven't cracked the diff itself yet.
The pinion still spins like before if I release it, but it's not acting like it wants to come out.
My press is 20 ton, so it should have plenty of push.
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Never mind. It finally let out a ping and the preload went away. (I checked after releasing the press.) It's now moving, but reluctantly. I expected a bang, but it was just a little ping.
The pinion still spins like before if I release it, but it's not acting like it wants to come out.
My press is 20 ton, so it should have plenty of push.
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Never mind. It finally let out a ping and the preload went away. (I checked after releasing the press.) It's now moving, but reluctantly. I expected a bang, but it was just a little ping.
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And, if anyone is thinking of buying the bearing and seal kit that Rock Auto sells ("TIMKEN DRK350")? Don't. The only bearing that fits is the front pinion bearing and it's not as beefy as the one from Toyota. The seals may fit - I haven't checked - I bought them from Toyota anyway. The pinion nut is also wrong. Maybe the kit works for the 2-pinion diff, but it sure doesn't fit mine (4-pinion 4.3 LSD).
Got the case apart, and my clutches and thrust washers are in an interesting stack on the ring gear tooth side. (I've not looked at the other side yet.) Unlike the TSRM drawing that shows them alternating, they are in this order:
(side gear)-tw-cp-tw-cp-cp-cp-tw-tw-tw-(case)
Hmmm...
(side gear)-tw-cp-tw-cp-cp-cp-tw-tw-tw-(case)
Hmmm...
Yea some things really need some effort to come apart. The inner pinion bearing race is unbelievable to get off. Wear safety glasses and stand behind something strong enough to catch flying hunks of metal just in case. Toyota is the place to go for the parts considering how long these have lasted from the factory.
What year is your differential? There was a TSB that deal with "Noise" that changed the way the clutches are stacked to allow them to slip easier. I cant seem to find the TSB right now.
What year is your differential? There was a TSB that deal with "Noise" that changed the way the clutches are stacked to allow them to slip easier. I cant seem to find the TSB right now.
Unfortunately, I don't know what year my diff is, as it's not the one that came with the car. I replaced the original about 15 years ago. The original diff stopped locking at all, and when I drained the fluid it was full of gold flakes. So, I headed to the recycler (junqueyard) and got a replacement. 4.3s are hard to find... I'll dig in my records tonight, but I'm not hopeful the receipt said what it came from.
Makes sense to stack the plates that way for noise reasons, but not for performance.
As I'm replacing the ring and pinion, I may not take off the inner pinion bearing. But, as I have to choose the spacer underneath, I'll probably get to put on and take off the new one at least once to set the pinion location properly. That will be fun.
I should've bought the bearing & seal kit from Driftmotion. Hindsight is 20/20.
Makes sense to stack the plates that way for noise reasons, but not for performance.
As I'm replacing the ring and pinion, I may not take off the inner pinion bearing. But, as I have to choose the spacer underneath, I'll probably get to put on and take off the new one at least once to set the pinion location properly. That will be fun.
I should've bought the bearing & seal kit from Driftmotion. Hindsight is 20/20.
Another note: you need to buy 4 clutch plates and 4 thrust washers. Nosechunks says in his very informative post, "This picture is missing two plates, the oil stuck it in the case." Actually, the two that stuck into the case are special factory-only pieces. They have friction material only on one side, unlike the ones you can buy that are coated on both sides. The TSRM mentions this, page RA-49 in the online version.
I would recommend reusing this 1-sided thrust washer, rather than a 2-sided one, so you don't wear away the case or shim. The shims go between the end washer and the case, so also should not get worn away.
I would recommend reusing this 1-sided thrust washer, rather than a 2-sided one, so you don't wear away the case or shim. The shims go between the end washer and the case, so also should not get worn away.
Now that i look at it, my comment about the two plates stuck in the case is actually wrong, There were actually THREE plates still stuck in the case.
Yes, Those outer plates are factory only plates, they are sized to give the proper clearance in the spider gears so the guys at the factory don't have to play with shims during assembly. There are 8 blank steel clutch discs and 10 checkered thrust washers in total in the differential. I would change all of them.
The top photo on this page of the TSRM is what your referring to about it being factory only. It also says "Therefore, Make adjustments with the adjusting shims and thrust washers that are available." The outer most "thrust washer" keys into the carrier so it always spins with the carrier. That means it cannot wear the carrier or the shim in any way. There is no reason to keep it.
You can see the thrust washer on top in this picture is the one that replaces the factory plate and goes against the case. It cannot turn once installed into the carrier. The shim would be placed on top of this thrust washer as it is shown in this picture and be sandwiched between it and the carrier. The only wear that plate sees is from the one clutch disc on the opposite side of it.
IF you do leave them, technically they could be too thick and not allow proper clearance for the spider gears. Its not likely, but i guess it could be possible because the factory plates thickness is that of a normal plate, PLUS the thickness of a shim.
Yes, Those outer plates are factory only plates, they are sized to give the proper clearance in the spider gears so the guys at the factory don't have to play with shims during assembly. There are 8 blank steel clutch discs and 10 checkered thrust washers in total in the differential. I would change all of them.
The top photo on this page of the TSRM is what your referring to about it being factory only. It also says "Therefore, Make adjustments with the adjusting shims and thrust washers that are available." The outer most "thrust washer" keys into the carrier so it always spins with the carrier. That means it cannot wear the carrier or the shim in any way. There is no reason to keep it.
You can see the thrust washer on top in this picture is the one that replaces the factory plate and goes against the case. It cannot turn once installed into the carrier. The shim would be placed on top of this thrust washer as it is shown in this picture and be sandwiched between it and the carrier. The only wear that plate sees is from the one clutch disc on the opposite side of it.
IF you do leave them, technically they could be too thick and not allow proper clearance for the spider gears. Its not likely, but i guess it could be possible because the factory plates thickness is that of a normal plate, PLUS the thickness of a shim.
Thinking about it more and looking at my carrier, I suspect it doesn't matter at all if the end thrust washers are 1- or 2-sided. They don't fit perfectly, so will rock back and forth a little, scrubbing slightly on the carrier, but it won't be much.
There's another clue I see: Page RA-53 shows one end thrust washer on the LH side without shading. Also, in the text for the 2nd picture from the top, they mention a thrust washer without an oil groove. Only the factory ones are like that.
Since my end thrust washers are in good shape, I will use them unless they're too thick. Both of mine are labeled with a "D" and are about 7 mils thicker than a new double-sided one.
I won't argue the wording in the TSRM could mean different things, and the drawings are not always 100% accurate.
We both agree that the backlash between the pinions and side gears is what's important.
(By the way, the instructions Weir supplies with their Maxgrip kit say to reuse the factory-only thrust washers. They also emphasize the importance of getting the pinion backlash correct.)
There's another clue I see: Page RA-53 shows one end thrust washer on the LH side without shading. Also, in the text for the 2nd picture from the top, they mention a thrust washer without an oil groove. Only the factory ones are like that.
Since my end thrust washers are in good shape, I will use them unless they're too thick. Both of mine are labeled with a "D" and are about 7 mils thicker than a new double-sided one.
I won't argue the wording in the TSRM could mean different things, and the drawings are not always 100% accurate.
We both agree that the backlash between the pinions and side gears is what's important.
(By the way, the instructions Weir supplies with their Maxgrip kit say to reuse the factory-only thrust washers. They also emphasize the importance of getting the pinion backlash correct.)
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Great thread, just read the whole thing. I could follow most of it.. but reading this makes me feel less bad about spending money on the shop I use.. lol.
It all sounds fairly straight forward, but I just picture myself doing it wrong as I tend to do one thing wrong whenever I pick up a wrench.
It all sounds fairly straight forward, but I just picture myself doing it wrong as I tend to do one thing wrong whenever I pick up a wrench.
Man, Nosechunks you weren't kidding about removing the rear pinion bearing from the pinion. I can't imagine using as 12-ton press as my 20-ton was straining. The bearing fights and bangs all the way off. I hope I don't have to do that very many times as I set up my new ring & pinion.
I bought an OTC 1123 bearing separator from Amazon for this. They have the best price I found. (Like the comments on Amazon say, where the nuts sit isn't smooth. I have access to a mill at work, so I spot faced them.) It fit fine without cutting off the roller cage.
I bought an OTC 1123 bearing separator from Amazon for this. They have the best price I found. (Like the comments on Amazon say, where the nuts sit isn't smooth. I have access to a mill at work, so I spot faced them.) It fit fine without cutting off the roller cage.
I have three photos to add to the mix.
For measuring the thickness of the clutch stack and side bearing, as well as the depth of the carrier, I found a way to use my dial indicator and magnetic stand. My dial indicator has only 1" of travel, so it can't measure these directly. Turns out my "LH Retainer" is exactly 1.200" long. So, it's easy to use the "LH Retainer" as a reference. The side gear and clutch pack is about 1.130", and the depth of the carrier is about 1.770". Two photos show how I measured. It's important to squish the clutch pack as it will compress 6mils or so.
Sure, I made some assumption about the flatness of my table. The side wings of my old table saw are flat enough for me.
The 3rd photo is my pinion in my press getting that huge rear bearing off. It's basically straight out of the TSRM, but thought I'd show it in case anyone wanted to see.
For measuring the thickness of the clutch stack and side bearing, as well as the depth of the carrier, I found a way to use my dial indicator and magnetic stand. My dial indicator has only 1" of travel, so it can't measure these directly. Turns out my "LH Retainer" is exactly 1.200" long. So, it's easy to use the "LH Retainer" as a reference. The side gear and clutch pack is about 1.130", and the depth of the carrier is about 1.770". Two photos show how I measured. It's important to squish the clutch pack as it will compress 6mils or so.
Sure, I made some assumption about the flatness of my table. The side wings of my old table saw are flat enough for me.
The 3rd photo is my pinion in my press getting that huge rear bearing off. It's basically straight out of the TSRM, but thought I'd show it in case anyone wanted to see.
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Another trick you could do for the pinnion bearing is if you are careful and good with a cut off wheel is like when cutting the inner race off a hub like when doing wheel bearings.
Remove the casing and roller bearings to get to the inner race. then use a cut off wheel and cut a slit going in the direction of the pinnion length wise. Dont go all the way through. JUst get close and the whole length of the race. Then use a hammer and chisel and a couple good wacks and the race should crack and slide right off.
Remove the casing and roller bearings to get to the inner race. then use a cut off wheel and cut a slit going in the direction of the pinnion length wise. Dont go all the way through. JUst get close and the whole length of the race. Then use a hammer and chisel and a couple good wacks and the race should crack and slide right off.