Rear End Rebuild?

85MUSTANGGT · 10-07-2006

I just picked up a '98 8.8" for my swap from a salvage. It appears to be in excellent shape and looks like as if it has been rebuilt recently. I was told it had 170,000 miles on it. I already have a set of 3.55 gears to put in it and I am wondering whether it would be wise to go ahead and replace the bearings and the clutches in the trac-lok. There are not any serious leaks, spins smooth, and both axles spin the same direction. The axle shafts wiggle slightly in the ends of the tubes, but I think that is normal. I haven't taken the inspection cover off so I don't know what the inside looks like yet. Should I do everything while it is out of the car and so I know everything is ok or just throw the gears in it.

lxarlo · 10-07-2006

with those miles, i would replace all the bearings, as well as the axle bearings and seals.

85MUSTANGGT · 10-08-2006

Thanks, thats what I was planning on doing. It just looked to be in such good shape I kind of hate to tear it open, but I guess it would be wise and easier while it is still out of the car.

FoxChassis · 10-08-2006

When you change the gearset you're going to have the differential housing and pinion bearings out anyway. A shop press will remove and reinstall the diff bearings. A slide hammer will remove the axle bearings.

While the housing is out of the car but the diff is in the housing is when the clutches are easiest to replace. You can add an extra clutch per side (and remove a spacer per side too) and a stiffer spring if you want.

85MUSTANGGT · 10-08-2006

Thanks for all the input! I really appreciate it. I will probably order the FRPP bearing/seal kit and the trac-lok rebuild kit this week. I got to thinking and I have to take the axles out to install the cobra rear brake kit anyway, so while I have it apart I just do all the bearings and seals while I'm saving up for the brakes.

Young_Buck · 10-08-2006

Agree with the Rebuild.

Why test it? It's better to overdue it than underdo it and risk major damage.

-YB

lxarlo · 10-08-2006

if you are goin to pay someone to do the gears or if you were planning on doing them yourself, id rather have the housing in the car so you can have it stationary while setting the pinion preload.

85MUSTANGGT · 10-09-2006

Yeah, I was planning on doing the gears myself, doesn't look too hard. I know someone that does it professionally that can help me if I run into problems. I will get everything disassembled and cleaned up this week. I can't wait to get the brakes done and find a set of wheels somewhere so I can start driving it again. Also you guys think it's easier to rebuild the trac-lok in the housing rather than doing it on the workbench?

FoxChassis · 10-09-2006

Depends on how tight the clutch/spacer pack is after re-packing it. Last time I added clutches and deleted spacers, even with the thinnest shims (.025"), I had a time re-inserting the pinion gears and their respective cups.

85MUSTANGGT · 10-09-2006

Thanks for the advice. I'll get it one way or the other. Once I start putting it together I can figure it out. Just waiting on payday to order the kits.

lxarlo · 10-10-2006

do the clutch packs on the bench, you have to take out the carrier to put on the ring gear anyway.

85MUSTANGGT · 10-10-2006

Alright, I took the inspection cover off last night and took te axles out. Everthing looks good other than the passenger side axle is "galled" where it rides in the bearing. It's not worn or grooved, just discolored more than anything. The drivers side axle has a clean polished surface across the bearing/seal area. Should I try polishing the passenger axle to try to clean it up (not remove material) or is this grounds for new axles? I wasn't planning on buying axles if I didn't have to. What would have caused the one axle to do this and not the other (misaligned bearing, dirt/trash)?

85MUSTANGGT · 10-11-2006

Tonight, I found some crocus cloth and polished the axle where the bearing rides and it looks a lot better. There is no wear there is just two thin rings in the bearing area that are pitted ever so slightly. I think it just got a little dirt or something in the bearing and it ran through. The bearing has worn the area to a mirror finish. The only thing is that the other axle is not like this. Should I still be concerned and am I still alright to use these axles? I would think they would still be ok to use.