Replacing rear diff in '02 4R (1 Viewer)

[marcfj60]

I finally got the '02 4Runner that I bought a couple years ago that's been stored at my dad's place over to my house this past weekend. I also have a rear diff/3rd member I got from a salvage yard to replace the one in the 4R that I think(hope) is responsible for the groaning/droning/whining sound coming out of the rear end at speeds over 20 mph. I'm curious what people would recommend for sealing it up when I reassemble it. I was sold a gasket that looks like a precisely cut piece of paper by AmToy. And I have a fresh tube of FIPG as well. The thought was that I would smear a thin layer on the diff hosing flange and apply the paper gasket to it. Then I'd apply another thin layer onto the axle housing flange and then bolt up the diff. Is this the right process? How long do I let the FIPG cure before putting oil in the differential?

I also plan to replace the axle seals while I'm in there because I have to remove them anyway to get the diff removed.

 

[FJCTom]

From my FJC FSM (which shouldn't differ) run a thin bead on both sides of the gasket. See excerpt picture. I believe Toyota FIPG cures in roughly 20 minutes. I can dig up the torque specs out of my 2003 Tacoma FSM which should be the same rear-end. Let me know.

 

[marcfj60]

From my FJC FSM (which shouldn't differ) run a thin bead on both sides of the gasket. See excerpt picture. I believe Toyota FIPG cures in roughly 20 minutes. I can dig up the torque specs out of my 2003 Tacoma FSM which should be the same rear-end. Let me know.

View attachment 2679368

this is good info. thank you and yes, a torque spec would be nice.

 

[FJCTom]

w/ Diff Lock - 18 ft.lbf

w/o Diff Lock - 54 ft.lbf

So I pulled these torques from my 2003 Tacoma FSM. If the 4R has the e-locker, I'm certain of the 18 ft.lbf as it is the same axle and carrier housings and I did a diff swap years ago.

I'm less sure on the axle w/o a diff lock as I've never worked or seen one. The 54 ft.lbf seems a bit high and would be advised to attempt to locate a T4R FSM to verify.

Picture attached from when I did my 2003 Tacoma to help ID the axle. It had the e-locker.

 

[marcfj60]

Thanks. This one is a non-locker, 3rd gen 4R. 2002 was the last year of the 3rd gen. I think I'll do some searching on the T4R forum to see if I can get some additional info.

 

[FJCTom]

I did a quick google search. Someone else tried the 54 ft-lb and snapped a stud. It does seem awfully high. Other folks are chiming in to say stick wth the 18 lb-ft.

Toyota-4Runner.org

The Largest 4Runner Community in the World

www.toyota-4runner.org

 

[pappy]

w/ Diff Lock - 18 ft.lbf

w/o Diff Lock - 54 ft.lbf

So I pulled these torques from my 2003 Tacoma FSM. If the 4R has the e-locker, I'm certain of the 18 ft.lbf as it is the same axle and carrier housings and I did a diff swap years ago.

Marc, my 1998 Gen3 4R FSM has these numbers too.

My 1985 manual has 19 ft-lb for the rear/front.

 

[marcfj60]

Making slow and steady progress. Got the 3rd member out this weekend. This job kind of sucks without a lift and a proper jack. I had the vehicle jacked up like a stink bug and on stands but still had barely enough room to get under it. Then I used a ratchet strap to secure the diff housing to my floor jack and got my daughter to help with dropping the jack and pushing/pulling it out from underneath it while I wrangled this 60lb hunk of junk from underneath. Everything is covered in what appears to be carbon. When turning the input/pinion flange by hand, there is a ton of slop and you can hear clanking/clacking sounds. And it feels rough when turning, to me indicating that the pinion bearing failed. I can't see any obvious damage on any gear faces and the spider gears/bearings appear ok when I turn it manually but I honestly wouldn't trust anything inside there at this point. Also was very relieved to find out that I had determined the right gear ratio a couple years back by turning tires and counting revolutions of the drive-shaft. I did a tooth count on the ring and pinion gears and came up with 43:11 (3.91) on the old one and the 'new' used unit I had purchased from a salvage yard in CA a couple years ago. Whew! Now I just need to spray a couple gallons of brake parts cleaner into the used one I bought because it's full of sand from the salvage yard that sent it to me.

 

[slimbuddha]

I have some taller jack stands, and a bottle jack that will go to 21" if you need them.

 

[Mauser]

Making slow and steady progress. Got the 3rd member out this weekend. This job kind of sucks without a lift and a proper jack. I had the vehicle jacked up like a stink bug and on stands but still had barely enough room to get under it. Then I used a ratchet strap to secure the diff housing to my floor jack and got my daughter to help with dropping the jack and pushing/pulling it out from underneath it while I wrangled this 60lb hunk of junk from underneath. Everything is covered in what appears to be carbon. When turning the input/pinion flange by hand, there is a ton of slop and you can hear clanking/clacking sounds. And it feels rough when turning, to me indicating that the pinion bearing failed. I can't see any obvious damage on any gear faces and the spider gears/bearings appear ok when I turn it manually but I honestly wouldn't trust anything inside there at this point. Also was very relieved to find out that I had determined the right gear ratio a couple years back by turning tires and counting revolutions of the drive-shaft. I did a tooth count on the ring and pinion gears and came up with 43:11 (3.91) on the old one and the 'new' used unit I had purchased from a salvage yard in CA a couple years ago. Whew! Now I just need to spray a couple gallons of brake parts cleaner into the used one I bought because it's full of sand from the salvage yard that sent it to me.View attachment 2697095View attachment 2697096

I've got a small transmission jack or can go by and help if you need it.

 

[marcfj60]

I've got a small transmission jack or can go by and help if you need it.

Thanks. I may need both when I can get to the install. Probably will be next weekend. This one is already pretty full.

 

[marcfj60]

I have some taller jack stands, and a bottle jack that will go to 21" if you need them.

I have two 6-ton that are huge and four 2-ton so I have enough I think. It's just jacking it up that high kind of freaks me out.

 

[marcfj60]

Never updated in this thread. Got it all swapped out a few weeks back. The torque value of 54 got scary so I kind of creeped up on it and stopped at about 45 when I was getting nervous that the studs were going to snap. Drove the vehicle to work for a couple weeks to make sure everything was working right and nothing sprung a leak since the vehicle sat with very limited engine starting for over 2 years. All seems good and Colin has been driving it to UNM for the past few days. I have forgotten how small and simple 20-year old 4Runners/Tacomas are compared to my Land Cruiser. Turns on a dime. Has a light, springy feel to it. I kind of liked it, other than the marginal power of the 3.4L 5VZ-FE is compared to the 4.0L 1GR-FE in my '05. When I had my '99 Tacoma with a manual transmission I always that that motor was pretty peppy. But my perspective was coming from an '86 2WD pickup with the 22RTE, which wasn't as fast as you'd think it should be.