V2 Diff rebuild + Gear Ratio Swap

[sapote]

The V2 is a pain in the ass. There is some adjustability in how much you turn the top plate. So you might have to test it, remove the LSD to make adjustment, retest it. It does loose locking torque so the one that I installed in my friend's car had to be removed, tightened, and reinstalled. And now it's not locking again. I'd stick with a V1.

V2 has the threaded lock ring to preload the clutch stack. Once set, it should work just like V1, so I don't know why V2 is not desirable in this regard. Unless the lock ring was not locked and it backed out.
Edited: The lock ring should be torqued to spec to bottom out, and it should not be used to adjust the clutch preload.

On top of the clutch stack, there is a cup washer to preload the clutch in V1 as I remember; does V2 have a similar spring washer? I believe it does in order to preload the clutch.

[bigjae46]

The V2 is a pain in the ass. There is some adjustability in how much you turn the top plate. So you might have to test it, remove the LSD to make adjustment, retest it. It does loose locking torque so the one that I installed in my friend's car had to be removed, tightened, and reinstalled. And now it's not locking again. I'd stick with a V1. I might have an extra one laying around...just need to install the clutch/steels.

You need a way to hold the LSD carrier and diff case...a really good way because you're putting a lot of torque on some of the fasteners.

The order of operation is...

Set carrier preload
Gear pattern
Backlash
Set pinion preload

There is a lot of installing stuff, removing stuff, reinstalling stuff.

If you have the pinion shim that came with the case, that should work. Haven't had to change it on any of the diffs I've rebuilt. With a 4.10...there is a possibility that you'll need a slightly thicker shim. That would be a PIA!

A 4.10 has a smaller pinion gear. Depending on if its a V1 or V2 - you have to reshim the carrier to move it slight closer to the pinion. If the carrier shims are both 1.7-ish, you probably will need a 1.6mm and 1.8mm shim. Your total shim thickness should be around 3.5mm.

1. Install carrier and LSD with shims - set preload - remove
2. Install pinion races and inner bearing on pinion gear
3. Press outer bearing onto pinion (no crush sleeve, no seal)
4. Press input flange and snug pinion nut
5. Install LSD carrier
6. Set gear pattern (adjust carrier shims)
7. Check backlash - should be really close if you have the gear pattern right
8. Disassemble the diff and press out the pinion
9. Slide crush sleeve over pinion
10. Repeat step #3
11. Set pinion preload
12. Assemble the rest of the diff
13. Check gear pattern and backlash again - x2 check

I use a big milwaukee impact to crush the sleeve. I give it two blasts until you get a hair of drag. Then one blast and check. You're much less likely to over crush the sleeve vs using a breaker bar IMO. Once the bearings start to drag (preload) it ramps up very quickly.

[sapote]

2. The installation tool is nothing but an M14 threaded shaft, to which the insert screws like a glove, it does not have the correct shape to form and expand the insert in place.]

The installation tool is a simple M14 with a stop, nothing special. I believe you have a fake Timesert; real one has the bottom compressed slightly so when the installation tool threaded through it expended and lock to the diff.

[maupineda]

All right. I received the copycat timesert kit and is not good. Here the issues with it:

1 - The tap just seems like a regular M16 metric tap thread, and it should be an STI tap.

2. The installation tool is nothing but an M14 threaded shaft, to which the insert screws like a glove, it does not have the correct shape to form and expand the insert in place.

3 The inserts, though inox, do not have the partially formed threads to lock the insert in place, although I already knew I couldn’t use these as they were very short, they are not actual inserts and rather threaded bushings.

Photos for reference. These will be returned and will get the real deal.

the kit…



See how the insert was screwed past the threaded end of the “install” tool.

[liam821]

I'm going to be tackling my diff here soon, so this is helpful. For me, I'm swapping to a 3.25 so I can use a DCT trans. Cheers for the links.

[sapote]

If you decide to use JBweld or thread-locker on the Timesert, then after installing the Timesert, turn the bolt in until it bottomed out and a little more to jack the Timesert out (preload it) to minimized JBweld between the loading threads before the compound set. This will maximize the strength of the Timesert.

[maupineda]

I have measured the shim sizes

the long one of the driver side is 1.75



the short on the passenger side is 1.45



I also measured the depth of the front bolt and is very deep, 39mm


I need to measure the bushing width and see what length of time-ser works best as is key to make sure the bolt ends passed the insert inside the cavity.

now, I measure the hole and is 12.7mm, by the look of it is like the threads are stripped, but I wonder if it is only corrosion and I should try a thread chaser first

[maupineda]

As long as the bolt gets to the end of the Timesert, it pushes out to expand the Timesert and lock to the diff. To avoid it backout, I added JB weld on the Timesert outside threads.

…

Btw, why you want to change the bearings? I assume the diff was removed bc the bad front mount threaded hole, so I would look at the roller bearing and outer races for any damages, and continue to use them if no damage. The clutch stack is worn I assume and need new parts, then add 2 output flange seals and 2 o-rings, and input seal.

this is very helpful!! Thanks Sapote

as for your question on bearings, the proceedings of the diff is unknown, I have no idea if it was quite, mileage, etc. the races and bearings seem fine, but I did see some color markings on the race. But is tough to assess by look and I do not have a precise way of measure race wear. I also have the Koyo bearings for the pinion and output shafts. I also have all seals and o rings.

[sapote]

[*]Use longest possible insert such as the bolt extends past the insert at least 1-3 turns/threads - need to measure this still
.

I had done 14 Timeserts for the head bolts on the block when my wife drove the car with no coolant for 8 miles -- enough to pull the threads out of the blocks on her 325iT.

As long as the bolt gets to the end of the Timesert, it pushes out to expand the Timesert and lock to the diff. To avoid it backout, I added JB weld on the Timesert outside threads.

Don't use a drill bit and hand drill to drill out the damaged threads as it will jam suddenly and might break. Maybe just use a masonry drill bit or something with no sharp edges.

Btw, why you want to change the bearings? I assume the diff was removed bc the bad front mount threaded hole, so I would look at the roller bearing and outer races for any damages, and continue to use them if no damage. The clutch stack is worn I assume and need new parts, then add 2 output flange seals and 2 o-rings, and input seal.

[maupineda]

This is the time-sert kit I went with. I hope I do not regret this as is a copycat. Also, the inserts in this kit do not work as some of the key characteristics for the repair to work according to Time-sert are:

https://www.amazon.com/dp/B09JNX2V87..._TE_sc_as_ri_0

• Use longest possible insert such as the bolt extends past the insert at least 1-3 turns/threads - need to measure this still
• I anticipate I will need the longest possible, which I think is 26mm
• Though not recommended by the manufacturer, I plan to use red Loctite as in my view this is a permanent repair and should not need to undo the insert.
• I plan to run the torque setting recommended for a 8.8 grade to be on the safe side, with also a bit of thread locker, which is 150NM and not the 200NM, this is 75% if the OEM recommended value, but I do not know if I stick to the OE spec I could back out the insert upon removal.

I was also thinking about using stainless, I know it has the potential of galling, which in this case may be ok to lock the insert there and avoid pulling out.

[maupineda]

That's correct, I have a 4.10 currently and like it but want to try a stock gear ratio. I town at low speeds around 35mph I am either way too high in the RPM's in 2nd gear or bogging it in 3rd not to mention when on the highway the RPMs are a bit high for my liking.

I fell a 3.91 would be about right or even a 3.85. I do want to keep both diffs so I can change my mind. I may just throw some new fluid in my spare 3.62 and try it out as it did come from a running vehicle.

I will likely install it as is decide if I like it, and if so then rebuild it. It will be unfortunate to loose the 4.10's "pep" but I feel the stock gearing might suit be driving environment better.

Yes, I plan for the same, have the two and see which I like the most, though swapping is such a PITA that I already know it will very likely be a one time deal lol. I find the 3.62 ratio barely okish for my use, when going on canyon drives I find second and 3rd kind of long and it should be pretty fun to have a peppier second coming out of low speed turn. At the same time the stock ratio have me either too high on revs if left in 2nd, but out of puff if left in 3rd. So it can be binary as 2nd is either short or long.

[Obioban]

That's correct, I have a 4.10 currently and like it but want to try a stock gear ratio. I town at low speeds around 35mph I am either way too high in the RPM's in 2nd gear or bogging it in 3rd not to mention when on the highway the RPMs are a bit high for my liking.

I fell a 3.91 would be about right or even a 3.85. I do want to keep both diffs so I can change my mind. I may just throw some new fluid in my spare 3.62 and try it out as it did come from a running vehicle.

I will likely install it as is decide if I like it, and if so then rebuild it. It will be unfortunate to loose the 4.10's "pep" but I feel the stock gearing might suit be driving environment better.

Stock gearing is perfect.

[Cubieman]

So you have 4.1 and want 3.62? Interested in a full unit swap instead? that is the whole reason I am doing this :P

That's correct, I have a 4.10 currently and like it but want to try a stock gear ratio. I town at low speeds around 35mph I am either way too high in the RPM's in 2nd gear or bogging it in 3rd not to mention when on the highway the RPMs are a bit high for my liking.

I fell a 3.91 would be about right or even a 3.85. I do want to keep both diffs so I can change my mind. I may just throw some new fluid in my spare 3.62 and try it out as it did come from a running vehicle.

I will likely install it as is decide if I like it, and if so then rebuild it. It will be unfortunate to loose the 4.10's "pep" but I feel the stock gearing might suit be driving environment better.

[maupineda]

My spare diff. also turned out to be a V2, I too have 4.10's I am trying to get away from so I will watching for updates!

I had told myself that I would just send it out but I need to be in money saving mode for a while unfortunately so a DIY rebuild makes sense for multiple reasons, unless I mess up.

So you have 4.1 and want 3.62? Interested in a full unit swap instead? that is the whole reason I am doing this :P

[Cubieman]

My spare diff. also turned out to be a V2, I too have 4.10's I am trying to get away from so I will watching for updates!

I had told myself that I would just send it out but I need to be in money saving mode for a while unfortunately so a DIY rebuild makes sense for multiple reasons, unless I mess up.