jarrodh77

iTrader: (20)

I just want to add one tip so nobody makes the same mistake I did. DO NOT put lube on the shims or around where the bearings/shims contact the inside of the pumpkin. This apparently doesn't allow enough clearance for the bearings to expand with heat. I was getting some nasty noises at low speeds once things heated up. After taking the rear end apart and cleaning the lube off, all the noises/vibrations are gone.

SDmattZ

Ok I just read this thread and I'm interested in doing this but I'm coming from the 4x4 world.

First, is the factory VDC disabled by installing either of these?

Second, is pinion depth not adjusted at all during this process? I'm used to a solid rearend requiring yoke removal

Third, what does 2 way refer to in the carbonetic diff? And does this differ wear out or require more frequent fluid changes from the heat/material?

Fourth, does the Quife essentially behave like a detroit locker? (open diff coast, 100% engagement under throttle) and if so does it cause the rearend to jerk or complicate shifts? My old jeep used to make people run for cover around corners

randing

VDC is electronic, not mechanical. It works independantly of the diff.

As others have stated and as with any diff install, backlash will need to be checked and adjusted as necessary.

2-way refers to a clutch-type diff that locks on acceleration and deceleration. 1.5 doesn't lock as tightly on decel and 1-way doesn't lock on decel at all.

It's closer to a TrueTrac than a locker. It uses worm gears the same way the TrueTrac does and it doesn't have the ratcheting on-off characteristics of a Locker, it's more transparent.

Ted J

Sorry to bring up an old thread but I had the same issue when I installed my Tomei into my 240SX. My dad use to be a diesel mechanic years ago and I called him up and he said to try the following and it worked great:

1. Tighten up the bolts and get them as tight as you can wearing a glove to make sure the ring gear is seated all the way onto the diff.

2. Install the ring gear and diff into the pumpking and tighten up the bearing cap bolts. (I didn't put thread locker on the bearing cap bolts yet for I was going to maybe need to remove it after checking the backlash)

3. Position the pumpkin in a way so that you can torque down on the ring gear bolts and it won't move around much. I think I ended up putting my foot on the front of the pumpkin to hold it down onto the concrete floor.

4. Take the ring gear bolts out one by one and put your thread locker on. (I like to come up with a system of marking the bolts, like when I put thread locker on I use a marker and do one line of an X and then once they are torqued I used the marker and fill in the 2nd line of the X to mark it etc...)

5. Now take a thick shop cloth (I used a red one that I had that didn't have a lot of lint to it and was fairly thick) and stuff it up into the gears and let the rag pinch between the gears and torque the ring gear bolts down in a crisscross pattern. (as you'd guess, torqued one, unloaded the rag, moved the ring gear around, put the rag back in) I went in two torque stages. Did it once at like half the torque spec and then the second time around I did them at the full torque spec and marked off the bolts that they were torqued.

Not the easiest way and a little ackward but just one way that turned out to work pretty good. I really didn't want to put mine in a vice for it was round like you had stated and I didn't want to scratch it up.

Also note that you'll want to make sure you clean any lint or debris that the rag may have left once you are done.

ian99rt

iTrader: (12)

I actually used the driveshaft flange with a grade 8 bolt in one of the holes contacting the housing. Not the best solution as it marred up the hole areas a bit but worked well.

I also had the front bushings out and used my 1.25" x 4 steel tube stuck in the bushing holes to leverage against.

Ted J

Cool, thanks for the post, always neat to learn new ways to 'skin a cat' so to speak!

mickeyboi

iTrader: (1)

Sorry for being a noob but I was trying to find info on gear marker and backlash. The link on page 2 is dead. Do I just put gear marker on 4 points of the drive gear and then rotate it in the housing to make sure it meshes up with the drive gear?

Also, is it likely that I will need additional shims or is it possible to make due with the shims that come in the oem pumpkin? Thanks!

rswails

Good writeup, but why did you not include torque specs? You took the time for all this info and then tell us to refer to FSM for torque. It would be nice if it was complete and you included that.

ian99rt

iTrader: (12)

I guess if your competent enough to do this install you would be resourceful enough to download the factory manual online.

rswails

First of all, you mean "you're" not "your". Secondly, I said "It would be nice if it was complete and you included that." I did not imply in any way I wasn't competent enough to read a FSM. I am just trying to improve the usefulness of the post. I believe it would be more useful with the torque specs included. If you enjoy following instructions from multiple sources, then we are not on the same boat.

ian99rt

iTrader: (12)

Glad to see your making friends on the forum and great at catching gramar errors from a playful poke.

So here is your torque specs (all in ft-lbs unless noted):

Ring gear bolts: 58, then 31-36 degrees rotation after.
Diff carrier saddle bolts: 69
Rear diff cover bolts: 32
Diff cover drain and fill bolts: 25

Technically me posting the torque specs here is a 3rd party source for info and should not be taken seriously. I am simply repeating the FSM numbers.

You want an animal cracker as well?

Buster-here

Yes. But sometimes it is also a good idea to deliberately leave critical info like that out so that they have to then refer to the FSM as well. Never know but maybe they will learn something else while they are there researching the torque settings.

Looking through the relevant section (Rear Final Drive) in the FSM I would think is a good idea before swapping out the diff even with this DIY.

Allen Hsi

can I reuse the original ring gear or I must get a new one? and I am thinking about just malleting it in instead of a press like someone suggested... what do you think?

ian99rt

iTrader: (12)

Ring gear can absolutely be reused, the ring gear bolts should not.

If you are referring to hammering on bearings instead of pressing, your going to need a very large hammer (10 lbs sledge), surgical precision, and a dose of luck. You will almost guaranteed destroy the new bearings trying to get them on, a 12 ton press from Harbor Freight is only about $100.

You could just pay a shop $25 to push on the new bearings. As long as your install and remove the diff / ring gear into the housing very square during bearing preload and backlash checks you shouldn't need to deal with the bearings anymore.

Elizab7eth

I am leaning toward the Carbonetics.

Fenvy

I am reading from 4 different thread toward the install and each thread made it clear that you must mark the positions.

some mentioned spacer, some mention flanges, while someone even mentioned ring gear.

1) what exactly am I suppose to mark? also wouldn't marking the ring gear pointless if I am replacing it with a new one?

2) what happens say if I didn't mark it correctly? this is not addressed in any of the thread I am reading

thank you!

B T

Why not re-use the ring gear bolts? I did on my 240sx 10 years ago and never had any issues.

ian99rt

iTrader: (12)

Ring gear bolts under heavy usage (drag racing especially) puts a lot of shear forces on the bilts and retorquing can cause yielding after the material has already been weakened from 35k + miles of use.

Plus its $35 to replace them, which you will really kick yourself if a broken bolt eats you $950+ diff, not to mention the bearings and gears.

BlaqMagic

Hey guys, just registered but been prowling for over a year. Has anyone done installs on a 5AT diff?

I bought the QDF10L, we pulled out the stock 5AT diff to find it had a 3.7FD with open diff, as you can see there's a height difference so the crown ring doesn't touch the pinion. I bought another 2nd hand diff, opened it up to find a 3.5FD in this one and the same distance issue. Does it need to be specifically a 3.35 ring/pinion set for it to work with the QDF10L for 5AT diff pumpkins?

Voboy

iTrader: (58)

^- Looks you got a swapped 3.7 + VLSD pumpkin.... that QDF10L model isn't going to work. Were the axle stubs out of that thing different lengths? That would also confirm its a VLSD... You'll need a the QDF13L...