Confused about rear axle

Topic: Confused about rear axle (Read 4122 times) previous topic - next topic

Confused about rear axle

May 21, 2015, 09:23:26 PM

I have 3 birds 2 r turbos. My daily driver is 88 TC the rear axle has roar and vibration I'm thinking pinion bearing but that different subject. What I'm confused about is I bought a 87 TC for parts was told all original. I did a 5spd swap and planned on swapping read axle but my parts car is a factory TC but it has a 7.5 rear axle with disk brakes. I have been researching and in 88 the TC came standard with 8.8 track lok 3.55 or 3.73 but y would my 87 TC have 7.5 limited slip disk brakes I searched and the 7.5 was not an option for 87-88 TC. Y and how would u get that rear axle with disk brakes n that car. Any input would b good I planned on putting that rear axle in my driver (which is 8.8 3.73 locker)

Confused about rear axle

Reply #1 – May 21, 2015, 09:32:13 PM

Could be from a v6 sn mustang

Are you sure it's a 7.5?

Confused about rear axle

Reply #2 – May 22, 2015, 12:19:46 AM

Quote from: STANG8U;448233

Could be from a v6 sn mustang

Are you sure it's a 7.5?

True. That's about the only way it could happen. No 87-88 Turbo Coupe made it out of the factory with a 7.5 rear axle.

Confused about rear axle

Reply #3 – May 22, 2015, 02:10:33 AM

OP, how's about a pic of the rear..

Confused about rear axle

Reply #4 – May 22, 2015, 09:12:10 AM

Didn't some of the earlier TC's have the 7.5 w/disk brakes? Maybe someone swapped it?

Confused about rear axle

Reply #5 – May 22, 2015, 10:39:50 AM

Nope, all 83-86 tc's and xr7's had a limited slip 7.5 with drums. Most were 10" drums but I've seen a few with 89" drums.

What's the axle tag say? 5 lug mustang rear disks don't fit a 4 lug hub properly.

Confused about rear axle

Reply #6 – May 22, 2015, 06:32:47 PM

Thanks for reply. I feel like a dummy car has a 3.55 locker 8.8 rear I thought it was different not sure how
good rear axle is not for sure locker works as good as mine guess ill swap and find out. Can I use clutches n my locker to fix other rear if there bad?

Confused about rear axle

Reply #7 – May 24, 2015, 01:32:34 AM

It's a limited slip, and it's a viscous clutch type.

If you open the rear, make sure you put in 4 ounces of friction modifier, most any auto parts place has it.

Confused about rear axle

Reply #8 – May 24, 2015, 10:34:03 PM

Rear axle tag code SL55 which should be 3.55 trak loc rear and my car has 3.73 trak loc could I just swap clutch packs cause rear axle works well in my car? Don't have money to spend all I have is parts. I have my parts car up and I check it both rear wheels turned same direction while rotating one or the other but it was sloppy ( while rotating one side or the other it wasn't tight like my when rotating I stop wheel and other didn't stop at same time both sides same way) that's why I figure clutches are shot and maybe I could swap them or would it be a bad decision considering there same axle but different gear different year and mileage

Confused about rear axle

Reply #9 – May 24, 2015, 10:53:39 PM

Its not that bad of a job to do and shouldn't hurt anything if the traction lock doesn't work. Your speedo would be off a bit if you swapped it. If i was going to rebuild the traction lock, id throw new fluid in it while i was there. Id save the the rebuild till you have enough money to do it.

Confused about rear axle

Reply #10 – May 25, 2015, 12:17:07 AM

Yea if there isn't a ton a play between the ring and pinion gear then I would leave it as is
What I would do while rebuilding the Trac-local is change out the wheel bearing and seals while you have those c-clips out
I got mine cheap at autozone

Confused about rear axle

Reply #11 – May 25, 2015, 12:54:06 AM

Thanks. The good news is the trans n my car came out of parts cars so that rear matches trans. I'd like to fix cause I know how my car is now. I guess little less playing lol. Could I swap the whole chunk and change ring gear. The problem with rear in my car is probably pinion barren loud roar and vibration and there could be some damage I haven't look at it but I do need 3.55 gear in my car considering I swapped it to 5pd

Confused about rear axle

Reply #12 – May 25, 2015, 10:18:21 AM

Thanks. A man said to me why don't I swap the chunk and change ring gear could that work? I shouldn't have problem with spdo being off cause trans in my car came out of parts car and that rear matches the trans

Confused about rear axle

Reply #13 – May 25, 2015, 10:21:01 AM

Didn't mean to post same thing again but my earlier post didn't show until after I posted last post

Confused about rear axle

Reply #14 – May 25, 2015, 02:28:40 PM

Quote from: wpblackfoxturbo;448291

Thanks. A man said to me why don't I swap the chunk and change ring gear could that work? I shouldn't have problem with spdo being off cause trans in my car came out of parts car and that rear matches the trans

AFAIK "chunk" refers to a 8" or 9" carrier, hogshead, whatever one calls it... Anyway you'll have to swap the whole thing as there is no "chunk"...

Unless you are a seasoned differential guy and know what you are doing, swapping gears without fresh shims, bearings, etc from one unit to another is almost asking for trouble(Hell I've seen it done numerous times and won't begin to attempt it)... Replacing the clutch packs is no big deal...

For the most part a turbo 4 gives a 8.8" a life of Riley, unless run low on lube gears/bearings are almost never bad... Clutches are generally toast around 100K mi...