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Removal & Installation of Rear Diff for Quaife LSD

3304 Views 24 Replies 8 Participants Last post by  IridiumRS400
Started the parts removal (i.e., exhaust, driveshaft, RSTB, etc.) this afternoon to allow for the removal of the OEM rear diff, since I decided to put my QJ's to use and perform the R&R of the rear diff myself, and then drop-off/pick-up the differential w/Quaife LSD installed by my race shop in Tigard. They can turn-around the LSD install in a few days, depending if the shims from the Infiniti dealership can be delivered overnight or not.

I'm currently at the step of removing the diff from it's mount. Looks like two bolts near the front, and one in back. Tomorrow, I'll be using a transmission jack to lower the diff while I pop the half-shafts out. Glad I have the 2016 Service Manual for reference - still have to drain the gear oil, remove both wheels sensors, and then the vent tube as the diff is lowered.

So looking forward to having a rear LSD for the approaching PNW wet season.
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@FD3TOE46 Any guesses on the weight of the rear diff?
@FD3TOE46 Any guesses on the weight of the rear diff?
I estimate roughly 40-50lbs range? For sure you don't want that thing landing on your head :)
I estimate roughly 40-50lbs range? For sure you don't want that thing landing on your head :)
Agreed... I already scraped my right shoulder on the rear subframe trying to wiggle out from under the car for the nth time yesterday.
NEXT UPDATE: The rear diff is out!

I drained out the gear oil before I started to loosen the diff mounts. Here's what the drain plug magnet looked like after 15k miles (my Q has 30k miles, and the driveline fluids were changed-out @ 15k miles):
Camera accessory Cameras & optics Gas Wood Electric blue
Gas Engineering Household hardware Auto part Electric blue

After the fluid drained out, I bungeed the park brake cables out of the way, and set up the rubber bungees for supporting the half-shafts later. The two axle speed sensors were removed, and I tucked them on top of the rear subframe.

I used the 800-lb transmission jack with its flat plate to hold the diff case while I removed the rear nut and the two bolts towards the front of the diff case. I enlisted the neighbor's help to make sure the diff didn't move off the jack's flat plate as we lowered it. We disconnected the vent line, and also pushed out the plastic rivet for the tubing retainer, too.

Everything went according to plan until trying to dislodge the half-shafts. My neighbor brought over a better prybar set than I had, and after trying to gingerly pry on the trigger wheel, which I know you're not supposed to do, we simply used a little more muscle and "popped-out" the splines. Despite what the SM says, the spacers just inboard of the trigger wheel can't be used as a prying point, because they never make it past the diff case. After sliding the half-shaft splines out, I moved the diff out from under the car. I wrapped the rubber bungees around each half-shaft to keep them from falling towards the floor, which, if left unsupported, would put unwanted stress on the outer CV joints.

Here's how it looks with the diff out of its usual space (yellow towels are there to keep the boots from getting nicked by sharp edges):
Outerwear Motor vehicle Automotive tire Automotive design Automotive exterior

Automotive tire Automotive design Motor vehicle Automotive exterior Rim

As for getting the Quaife LSD installed, it looks like early Monday morning me and the Mrs. will put the diff into a sturdy container, load it into the SQ5, and travel down to the Tigard-area race shop, since I'm not fond of Fedex Ground delivery right now. Besides, I'd like to finally meet Martin, who owns the shop and previously installed the RS-R C/Os & SPL Parts suspension bits last May (we've never met in-person).

One question - any significance to the purple marking on the diff mount spacers shown above? I didn't make a mental note of their clocking when removing the diff.
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NEXT UPDATE: The rear diff is out!

I drained out the gear oil before I started to loosen the diff mounts. Here's what the drain plug magnet looked like after 15k miles (my Q has 30k miles, and the driveline fluids were changed-out @ 15k miles):
View attachment 102853 View attachment 102854
After the fluid drained out, I bungeed the park brake cables out of the way, and set up the rubber bungees for supporting the half-shafts later. The two axle speed sensors were removed, and I tucked them on top of the rear subframe.

I used the 800-lb transmission jack with its flat plate to hold the diff case while I removed the rear nut and the two bolts towards the front of the diff case. I enlisted the neighbor's help to make sure the diff didn't move off the jack's flat plate as we lowered it. We disconnected the vent line, and also pushed out the plastic rivet for the tubing retainer, too.

Everything went according to plan until trying to dislodge the half-shafts. My neighbor brought over a better prybar set than I had, and after trying to gingerly pry on the trigger wheel, which I know you're not supposed to do, we simply used a little more muscle and "popped-out" the splines. Despite what the SM says, the spacers just inboard of the trigger wheel can't be used as a prying point, because they never make it past the diff case. After sliding the half-shaft splines out, I moved the diff out from under the car. I wrapped the rubber bungees around each half-shaft to keep them from falling towards the floor, which, if left unsupported, would put unwanted stress on the outer CV joints.

Here's how it looks with the diff out of its usual space (yellow towels are there to keep the boots from getting nicked by sharp edges):
View attachment 102855
View attachment 102857
As for getting the Quaife LSD installed, it looks like early Monday morning me and the Mrs. will put the diff into a sturdy container, load it into the SQ5, and travel down to the Tigard-area race shop, since I'm not fond of Fedex Ground delivery right now. Besides, I'd like to finally meet Martin, who owns the shop and previously installed the RS-R C/Os & SPL Parts suspension bits last May (we've never met in-person).

One question - any significance to the purple marking on the diff mount spacers shown above? I didn't make a mental note of their clocking when removing the diff.
I can't find any reference to those purple markings in the SM regarding their alignment.
I can't find any reference to those purple markings in the SM regarding their alignment.
Thanks Tin Man. Looking at the spacers, nothing appears unique, so I've concluded they must have been markings at the factory to signify the two front mounting bolts were torqued to the installation spec.
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Thanks Tin Man. Looking at the spacers, nothing appears unique, so I've concluded they must have been markings at the factory to signify the two front mounting bolts were torqued to the installation spec.
That's usually the case, as simple mark to indicate they've been torqued to spec. Although they typically have it on the bolts themselves not the component itself which
is a bit strange. Hah
UPDATE (2): Dropped-off the rear diff, or "pumpkin" on Monday (9/21), as planned.

Well, I received an email from the shop this evening (9/21) and it's all buttoned-up and ready to be shipped-back tomorrow. They will ship it Fedex Express, because unlike Fedex Ground, it's not a s**tshow. Paying an extra few bucks to get it back without spending weeks in a Fedex Ground trailer is worth the extra $.
UPDATE (3): Received the diff via UPS this morning (9/23). After starting the install, my neighbor and I realized the circlip on the right inboard CV shaft is missing, so I had to order one through the Infiniti dealer ($6.42). I search all over for it, even call the shop and asked if they found it in the OEM carrier, but no dice. Oh well, I'll likely find it on the aggregate driveway some day in the near future. The circlip should arrive at the dealer on Saturday.

I should be able to finish the install on Saturday, but it will still be a couple of weeks before I can try it out, as I decided to remove my anodized Aluminum-colored Stoptech calipers and send them out for a rebuild and a color change.
I estimate roughly 40-50lbs range? For sure you don't want that thing landing on your head :)
BTW, the shipping weight for the differential was 70 lbs.
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BTW, the shipping weight for the differential was 70 lbs.
yeah...Im late to the game, but when I got the crate from Z1 with a complete rear diff, I thought it felt more like 100.
yeah...Im late to the game, but when I got the crate from Z1 with a complete rear diff, I thought it felt more like 100.
The race shop wrapped the diff in a plastic bag, then foamed in-place within a thick-walled cardboard box.
Now that I had my shop install the Quaife LSD, here's the break-down for the LSD upgrade:

Quaife LSD (from CZP)--------------------$1,299
Full Bearing & Seal Kit (from Z1)-----------$366 (includes tax)
Labor to Install LSD in Diff Housing--------$600

Total---------------------------------------$2,234 + shipping

Compared to Z1's drop-in replacement w/core charges ($600) for $2,298 + taxes + shipping. Obviously, you can save over $500 with the Z1 option, but I had my intentions of getting the Wavetrac, until they developed quality control issues, so I opted for the Quaife, which has a solid rep.
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Now that I had my shop install the Quaife LSD, here's the break-down for the LSD upgrade:

Quaife LSD (from CZP)--------------------$1,299
Full Bearing & Seal Kit (from Z1)-----------$366 (includes tax)
Labor to Install LSD in Diff Housing--------$600

Total---------------------------------------$2,234 + shipping

Compared to Z1's drop-in replacement w/core charges ($600) for $2,298 + taxes + shipping. Obviously, you can save over $500 with the Z1 option, but I had my intentions of getting the Wavetrac, until they developed quality control issues, so I opted for the Quaife, which has a solid rep.
mine is working fine for a good 20k miles.

I was a bit bummed when I got it because it was supposed to come with a new core.

The shop that installed it, sanded it and painted it black. It has held up.
Geez that's not cheap. Practically at solid axle or fabbed rear end money. I haven't heard of too many failures even from racers so I guess it means the setup is strong.
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UPDATE (4): The circlip arrived at the dealership this afternoon (9/25), so I made the one-hour RT trek to go get it. Once back at the house, I was able to install the circlip by hand with a small amount of wheel bearing grease. We determined the best way to drive the CV joint shaft into the diff (must overcome the circlip tension) was to install the diff with the two mounting bolts in front and the rear nut, and then use a block of wood on the rubber boot where it meets the CV housing. That would give the axle spline a straight shot (not at an angle). A few swings with hammer on the wood and the axle spline was fully-seated.

With that out of the way, I proceeded to torque the diff mounts to spec (74 ft-lbs for the two front bolts, and 77 ft-lbs for the rear nut). I re-installed the IE driveshaft (D/S), which with its lighter weight and one-piece design, can be installed with one person. The only issue that came up - I couldn't torque two of the four bolts at the front flange of the D/S, as they were at the top, because my Q is in Park, and to rotate the D/S, it has to be out of Park. However, moving out of Park means pressing the brake pedal, and I can't do that because I would blow the caps off the brake lines, since my calipers are off getting rebuilt. I debated screwing with the brake pedal switch, but I opted not to.

Oh well, my remaining tasks on the driveline are filling the diff with fluid, torque the front D/S flange bolts, re-installing the FI X-pipe and mufflers, and re-installing the tunnel brace. It can wait until I get my calipers back, which should be no more than 10 work days from today.
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UPDATE (4): The circlip arrived at the dealership this afternoon (9/25), so I made the one-hour RT trek to go get it. Once back at the house, I was able to install the circlip by hand with a small amount of wheel bearing grease. We determined the best way to drive the CV joint shaft into the diff (must overcome the circlip tension) was to install the diff with the two mounting bolts in front and the rear nut, and then use a block of wood on the rubber boot where it meets the CV housing. That would give the axle spline a straight shot (not at an angle). A few swings with hammer on the wood and the axle spline was fully-seated.

With that out of the way, I proceeded to torque the diff mounts to spec (74 ft-lbs for the two front bolts, and 77 ft-lbs for the rear nut). I re-installed the IE driveshaft (D/S), which with its lighter weight and one-piece design, can be installed with one person. The only issue that came up - I couldn't torque two of the four bolts at the front flange of the D/S, as they were at the top, because my Q is in Park, and to rotate the D/S, it has to be out of Park. However, moving out of Park means pressing the brake pedal, and I can't do that because I would blow the caps off the brake lines, since my calipers are off getting rebuilt. I debated screwing with the brake pedal switch, but I opted not to.

Oh well, my remaining tasks on the driveline are filling the diff with fluid, torque the front D/S flange bolts, re-installing the FI X-pipe and mufflers, and re-installing the tunnel brace. It can wait until I get my calipers back, which should be no more than 10 work days from today.
Make yourself a note to torque the remaining bolts and put it in a prominent location so you don't forget to do so. Your enthusiasm once you get the calipers back will wipe that mental reminder right out of your brain.
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Make yourself a note to torque the remaining bolts and put it in a prominent location so you don't forget to do so. Your enthusiasm once you get the calipers back will wipe that mental reminder right out of your brain.
Imagine that - I looked in the owner's manual for a Shift Interlock Release, so that I could finish torquing up the transfer case side of the D/S flange since I couldn't move the brake pedal.

Bingo!
Font Parallel Elbow Document Slope

After some delay in the caliper rebuild, due in-part to sourcing the Stoptech piston and dust seals for my calipers, and I wanted the housing halves split during the paint process, I should finally have them back in my possession this week.

Pics of calipers after rebuild without housing bolts, caliper bridge plate, or interconnect tube installed::
Automotive lighting Cleat Toy Automotive design Red

Normally, on the red caliper bodies, the Stoptech branding is white:
Automotive design Orange Motor vehicle Font Hood

Automotive lighting Orange Automotive design Font Automotive exterior

I didn't really want the Stoptech branding to stand out on these re-finished calipers, so I opted keep the caliper bodies one color. The branding wasn't standing out when the caliper bodies were the original anodized Aluminum finish, but the calipers didn't stand-out either.
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dang op iridium, patience of a saint

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