Need complete rear-end rebuild... thinking of moving to 8.5"

**ScrapMaker** · 05-03-2006, 12:21 PM

My car has been making this noise from the rearend since I bought it, but has become increasingly louder in the last few months... it sounds like metallic rubbing/clattering when I coast, or turn slowly... it's almost a guarantee that the axle bearings are bad, which is eating a groove into the axle shaft.

now, I have gotten a quote from a shop to replace EVERY component, except the housing on my 7.5" for $1350... but I figure, that seems like a waste of money on such a weak rear-end...

now, I did some research, and the GM 8.5" rear-end is probably what I want... if at all possible, I'd want a simple swap, then have the rear-end rebuilt as necessary...

so my question you guys, is what is involved in switching to the 8.5"?? I know they can handle much more power than I will ever throw at them, and the price of a 12-bolt/Moser is way out of my range...

I'd feel like I was stabbed in the back if I rebuild this crummy-old 7.5" which is why I wanna do the swap...

is there any way to keep my rear disc, ABS, and TCS? Thanks because those are eseential to me...

**Bigrus** · 05-03-2006, 09:21 PM

wish i knew

**ScrapMaker** · 05-04-2006, 06:27 AM

I'd love to get the 8.5" but I have no idea how to bring over the ABS and TCS... or the discs, for that matter... because I think I need all-new axles too...

**zerogravity58** · 05-06-2006, 06:45 AM

i switched from a 7.5 to a 8.5 in my S10 and used camaro rear disk from a 4th gen on my 8.5, was a direct swap, as for the TCS and ABS i dont have those...

**notsomellow** · 05-06-2006, 07:24 AM

I have a 7.5 with 410 gears for $200 if anyone is interested. Added 100 shot of juice so I upgraded to a Moser 12 bolt with 411 gears, 35 spline axles.

**ScrapMaker** · 05-06-2006, 09:24 AM

Does anyone know how much better, and how much work there is involved with putting the Moser 7.5" on these cars?

They sell at about $475 on Moser's website... but what does that include? Does that have ALL the internals, or just the limited-slip part, or what??

Also, would the Moser 7.5" be a direct swap?

**notsomellow** · 05-06-2006, 12:59 PM

If you're going Moser why get a 7.5? 8.5 is the smallest carrier you should even think of getting. What you should do is save up for a while and get a Moser 12 bolt with a detroit locker. My buddy Bob Beam at Exotic Performance Plus has sold over 60 Mosers with this locker and has yet to have a complaint!

My 12 bolt was fairly simple to install. I did have to go get some 3" exhaust u bolts to mount the sway bar to the larger axle tube and while I was down there I installed lower control arm relocation brackets. Other than that, I had no problems w the u joints, shock and spring locations, or the abs sensor. Fyi, if you go ford 9" you lose ABS. Check out EPP's web site.

**0rion** · 05-12-2006, 10:19 PM

My vote would be for a new 12 bolt instead. No way would I dump that kinda cash into a 10 bolt rear. You have an a4 like I do but that still doesn't mean a 10 bolt will last. My posi was going out so I bought a Strange 12 bolt that was a complete bolt in. Strange has sway bar mounts already on the rear so no need to get the U-bolts, they have the through bolt torque arm mount instead of the 4 small bolts the moser has which are famous for causing problems, and they show up pre-assembled so you never have to turn a wrench on them. All of this for just a few hundred more than your 10 bolt rebuild. Check out billingsleyracing.com

**ScrapMaker** · 05-13-2006, 08:24 AM

so with the Strange 12-bolt... I will be able to keep my ABS and TCS... and there's absolutely no modification required?? works with stock axles and everything?

**0rion** · 05-13-2006, 07:14 PM

The Strange rear is a complete bolt in. It comes with axles and abs/tcs sensors. The only thing I had to do was solder on my plug for my abs but I have a 3 channel rear with the reluctor inside the pumpkin. A 4 channel rear uses the reluctor wheel on the axles. You can have them build either right into the rear. I caught it during a sale billingsley was having and got 5% off. I think it worked out to $2600 shipped but I also got the upgraded cover with the bearing cap studs.

**ScrapMaker** · 05-13-2006, 07:35 PM

hrm... damn that's a tuff decision... I don't plan on turning my car into a drag racer... and I can have it rebuilt to stock specs with new axles and everything for $1300... that's half the price, and it's possible it will last the life of the car...

ugh...

**keliente** · 05-18-2006, 05:51 AM

Originally Posted by ScrapMaker

hrm... damn that's a tuff decision... I don't plan on turning my car into a drag racer... and I can have it rebuilt to stock specs with new axles and everything for $1300... that's half the price, and it's possible it will last the life of the car...

ugh...

It's more than half really, worse comes to worse you could find a used 12 bolt for 1800 or so.

I would NOT put $1300 into something that "might" work. If you're not willing to go 12 bolt/s60/9inch then I would just continue to limp along on a 10 bolt. But otherwise just hack up the $$ for it. Even if you never dragrace the peace of mind is nice...

**ScrapMaker** · 05-18-2006, 12:10 PM

well if an aftermarket rear is $2600 + labor... then having the stock rebuilt is less than half...

I don't think my rear is bad though, just the axle bearings.... how do you know when the actual differential is going out?

and I don't know if I'll be able to find a used 12-bolt that has the ABS and TCS... seems a bit tough since anyone that has one, either paid $3000 for it, or had a standard 12-bolt customized...