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Discussion Starter · #1 ·
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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Discussion Starter · #2 ·
@FD3TOE46 Any guesses on the weight of the rear diff?
 

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Discussion Starter · #4 ·
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.
 

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Discussion Starter · #5 · (Edited)
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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Discussion Starter · #7 ·
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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Discussion Starter · #9 ·
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 $.
 

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Discussion Starter · #10 ·
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.
 

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Discussion Starter · #11 ·
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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Discussion Starter · #13 ·
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.
 

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Discussion Starter · #14 ·
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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Discussion Starter · #17 ·
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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Discussion Starter · #19 ·
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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Discussion Starter · #21 ·
dang op iridium, patience of a saint
Yeah, the caliper guy is retired from the day-to-day business, but still does caliper rebuilding and painting, except he's a crew of one vs a half-dozen when his shop was operating. Therefore, he does the work on his own schedule. He does excellent work, including finding a couple of the piston bores on my Stoptech caliper that needed "cleaning-up", as I believed one of the front calipers was dragging.

I could have just done the LSD install, and with my race shop turning it around in a couple days, it would have taken less than a week of downtime.

Fortunately I have our newest acquistion - a '21 Audi SQ5 Sportback, to serve as the stand-in until my Q is re-assembled.

BTW, slide hammer and wedge? I used a simple pry bar to pop-out the half-shafts.
 

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Discussion Starter · #22 ·
So in parallel with the LSD installation, after 4 weeks waiting for my Stoptech calipers to be rebuilt and painted, I picked them up yesterday. Pics don't do these justice - the resin paint, which is applied and oven baked-on, looks amazing. All the piston seals and dust seals were replaced. During the disassembly and rebuild process, one of the six pistons in each of the front calipers were found to be sticky, so that condition was corrected.

Front calipers (w/new Hawk HPS Pads installed):
Hood Vehicle Motor vehicle Automotive design Bumper

Hood Motor vehicle Automotive lighting Bumper Automotive design

Rear calipers:
Vehicle Car Hood Motor vehicle Automotive design

White Automotive design Automotive lighting Vehicle Toy

Beauty shot (Dining Room Table makes a great staging area):
Vehicle Automotive lighting Hood Automotive design Automotive tire

Next step - installation on my Q, which should be done by this weekend.
 
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Discussion Starter · #24 ·
I missed it somewhere along the line, were these used ones you bought or ones you had bought new and were to the point they needed a rebuild?
The calipers, along with the rest of the BBK, were bought used, with about 17k miles, mostly DD, but with some track usage thrown-in, according to the previous owner.
 
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Discussion Starter · #25 ·
Got the calipers installed and the brake system bled last night. Only hiccup I ran into was the rear calipers were re-assembled by my rebuilder/painter with the pad guide plates installed with both tension plates (#9 below) installed on the in-board side of the caliper. The tension plates (my name for them) have a bump which keeps a side load on the pads as they travel/translate with piston pressure.
Font Motor vehicle Auto part Rectangle Parallel


The end result was one pad dropped-in and the other pad would not, with not enough width for the pad. I had to remove one tension plate and replace it so that its partner was the smooth (no bump) plate. Apparently Stoptech figures their calipers would never be rebuilt LOL, so they didn't bother to Murphy-proof these slightly different guide plates.

After I figured that out, the rest of the install was uneventful.

Pics below are after a wash and shake-down run:
Wheel Car Tire Vehicle Sky

Wheel Tire Vehicle Car Automotive tire

Wheel Tire Car Vehicle Hood

As for the Quaife LSD, what a change from the stock open diff (Duh!)...

It's fun to put the power down on a corner exit - the rear end just hooks and the car launches. I have to re-adjust both the driver and the car for higher speed turns - the car has more understeer with the LSD, which is not a surprise. I have the Hotchkis Rear STB set at the middle position right now, I'll move it up one setting to see if that makes any difference in how the car rotates.
 
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