DIY rear diff mount replacement
#1
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DIY rear diff mount replacement
I was inspecting my car for a track day and discovered that a bunch of fluid had exploded from the left rear diff mount all over my trunk pan. OK, time to replace it.
First, buy a new diff mount. (I bought two, figuring that I'd rather not do this job again real soon).
The general strategy is to get the rear sway bar out of the way, then undo the nut that holds the diff to the mount, then undo the four bolts that hold the mount to the chassis, then pull the mount off and replace it.
Step number 1: Getting the sway bar out of the way. I unbolted both brackets and the swaybar became loose. I also undid the links from the sway bar with the intention of removing it. But I couldn't get it out of there. (I have modified my suspension, and maybe it's easier to get the dang thing out with stock suspension.) Anyway, it turned out to have enough play that I could work around it. (I also removed one of the exhaust rubbers, giving me a bit of play in the exhaust as well.)
Step number 2: Undo the nut and bolts holding the mount to the diff and the chassis. You need to detach the rear mounts from the diff (big center nut) and also detach the mounts from the chassis (four corner bolts). Not entirely the easiest access, but this is doable.
Step number 3: Remove the mount. Whoa!!! There's actually some substeps here.
3a: Get a jack and support the diff.
3b: Undo all four diff mounts (which is why it's a reasonable idea to replace both mounts at the same time). You only have to unscrew the front mounts from the chassis -- you can leave them attached to the diff. (One of the bolts is tough to get to without removing the evap canister, but I managed to do it.)
3c: Now you have enough play with the diff to get the mounts off the studs they are sitting on. You need to lower the diff down, then push one side of it forward. That will give you just enough room to get the mount off. Take a good look at the mount before it comes off, though, so you know for sure which way to orient the replacement mount. (Also tilt the diff the other way and do the other mount, if you are going to do both.)
Installation is done in reverse order. You will probably need to put the new rear mount(s) in, then move your jack up to the front of the diff and lift the front of it to get the front mounts in place again.
Torque everything as specified in the Helm manual. Torques range from 32-55 ft-lb.
First, buy a new diff mount. (I bought two, figuring that I'd rather not do this job again real soon).
The general strategy is to get the rear sway bar out of the way, then undo the nut that holds the diff to the mount, then undo the four bolts that hold the mount to the chassis, then pull the mount off and replace it.
Step number 1: Getting the sway bar out of the way. I unbolted both brackets and the swaybar became loose. I also undid the links from the sway bar with the intention of removing it. But I couldn't get it out of there. (I have modified my suspension, and maybe it's easier to get the dang thing out with stock suspension.) Anyway, it turned out to have enough play that I could work around it. (I also removed one of the exhaust rubbers, giving me a bit of play in the exhaust as well.)
Step number 2: Undo the nut and bolts holding the mount to the diff and the chassis. You need to detach the rear mounts from the diff (big center nut) and also detach the mounts from the chassis (four corner bolts). Not entirely the easiest access, but this is doable.
Step number 3: Remove the mount. Whoa!!! There's actually some substeps here.
3a: Get a jack and support the diff.
3b: Undo all four diff mounts (which is why it's a reasonable idea to replace both mounts at the same time). You only have to unscrew the front mounts from the chassis -- you can leave them attached to the diff. (One of the bolts is tough to get to without removing the evap canister, but I managed to do it.)
3c: Now you have enough play with the diff to get the mounts off the studs they are sitting on. You need to lower the diff down, then push one side of it forward. That will give you just enough room to get the mount off. Take a good look at the mount before it comes off, though, so you know for sure which way to orient the replacement mount. (Also tilt the diff the other way and do the other mount, if you are going to do both.)
Installation is done in reverse order. You will probably need to put the new rear mount(s) in, then move your jack up to the front of the diff and lift the front of it to get the front mounts in place again.
Torque everything as specified in the Helm manual. Torques range from 32-55 ft-lb.
#5
Registered User
Nope. Pull the 4 bolts and the diff nut off and it slides out the rear. Very easy.
EDIT: Disregard. you have to have the diff loose to change them. Sorry for the brain fart.
EDIT: Disregard. you have to have the diff loose to change them. Sorry for the brain fart.
#7
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Join Date: Dec 2000
Location: Bellevue WA
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Just thought i'd add a bit to this that wasn't very clear, I just did this on a friend's car today.
1: drop the rear-most exhaust hangars, not the ones closest to the diff, they're easier to get off and give you wiggle room.
2: This wasn't very clear, but you need to pull all 4 front diff bolts that go vertically to the mount near the driveshaft. I loosened them to get slack, and had no luck. Fought for an hour until i just pulled the four with the diff on a jack. BAM, the diff was able to move forward and the rear mounts slipped on in about 2 seconds. The axles and evap crossmember hold the diff up, i used the jack just in case.
3: The ONLY things you need to pull are the swaybar (but you do NOT need to remove it form the car, work around it), the 8 mount surround bolts, the 2 rear mount center nuts, and the 4 diff bolts up front.
... just more info for the next guy.
1: drop the rear-most exhaust hangars, not the ones closest to the diff, they're easier to get off and give you wiggle room.
2: This wasn't very clear, but you need to pull all 4 front diff bolts that go vertically to the mount near the driveshaft. I loosened them to get slack, and had no luck. Fought for an hour until i just pulled the four with the diff on a jack. BAM, the diff was able to move forward and the rear mounts slipped on in about 2 seconds. The axles and evap crossmember hold the diff up, i used the jack just in case.
3: The ONLY things you need to pull are the swaybar (but you do NOT need to remove it form the car, work around it), the 8 mount surround bolts, the 2 rear mount center nuts, and the 4 diff bolts up front.
... just more info for the next guy.
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#9
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Took me ~3h ****ing around and doing it the wrong way. Had I done it properly? Probably an hour, hour and a half.
Need a shallow 14mm and a deep 14mm for the swaybar. Possibly an allen key and 14mm end wrench if the endlinks aren't cooperating.
19mm end wrench for the center nuts on the mounts, 14mm shallow for the surrounding bolts.
19mm half-drive or a breaker bar for the front 19mm bolts on the diff.
some penetrant for the exhaust hangars.
Not too bad, really.
Need a shallow 14mm and a deep 14mm for the swaybar. Possibly an allen key and 14mm end wrench if the endlinks aren't cooperating.
19mm end wrench for the center nuts on the mounts, 14mm shallow for the surrounding bolts.
19mm half-drive or a breaker bar for the front 19mm bolts on the diff.
some penetrant for the exhaust hangars.
Not too bad, really.
#10
Just did all four on my AP1, and I am assuming that the your car has updated liquid filled mounts, either that or the mounts on the car I bought were broken for that long !!
Yours have a vacuum nipple on them ?
Yours have a vacuum nipple on them ?