Finally got one in hand. Still not exactly sure what it is though. Help me determine for sure?

https://www.thirdgen.org/forums/tran...3-08-posi.html

I think it is a Borg Warner 9 bolt with 3.23 posi and single piston disks. Was there any other gear combo in an '98 GTA with a 9 bolt?

H, tell Jason I couldn't wait plus this was an awesome deal. I hope he's doing better too!

 

It's either a 2.77, a 3.27, or a 3.45. The tag on the differential cover should be stamped with a ratio, or you can take the cover off and count the teeth on the ring and pinion gears.

 

also 3.45 only came in 5 speed cars, and most if not all 350 gta got the 3.27

 

It's probably a 3.27 Mike.
Check the tag like Jeremy said, it will be a bit backward looking.

 

Oops... I forgot the GTA gear was a 3.27. That's even better actually.

More pics attached. I don't see a tag with something resembling a ratio number. Also, I think it may be ready to install after I get the rotors turned, pads replaced, diff fluid changed (Royal Purple?). Trans gear... List is getting long.

At this point I'm curious about a disk/drum e-brake conversion. Is it the same mechanism?

 

i tell him that glad u got the rear. jason is doin well btw

 

You just need e-brake cables to match the type of brakes you have, your drum cables won't work. Just buy a set of '89 disc cables from NAPA or your dealer might still have some available.. I was able to get some GM ones a couple of years ago.

 

What about a speedometer gear? Another NAPA possibility?

Found the 3.27 tag on the diff cover...

 

The gears you have to get from the dealer. I had the part #'s written down but can't find them. They're not much, like $20.

 

Yeah... I'll find one. Not worried.

At this point I've looked over the axle and am quite happy. It's much cleaner than the one I have now and it surely has fewer miles. The brakes are going to be really nice and the torsion bar (is that what it is called?) is much thicker, than what I have now. I need some learning on that one. What does that bar do and why is it better to have it thicker? Obviously stiffer is better...

Anyway, here is the list of instructions to the mechanic when I deliver the part to him:

1. Remove old axle, inspect rear shocks, replace if necessary.
2. remove old rotors and determine if they are in spec. If so, turn them and install new pads.
3. Bleed brakes.
4. Install new e-brake cable.
5. Install speedo gear.
6. During entire process, replace any worn out bushings if needed.

What am I missing? Should I get a new master cylinder to power 4 disks now?

 

Sound great bro! When is the last time you replaced your rear shocks?

 

You dont need a new master cylinder or proportioning valve, as the 82-92 disc/drum brake one is the same as the 89-92 disc/disc one.
The only "bar" I can think of on the rear end would be the rear anti-sway bar. Having a thicker one resists twisting and helps the car drive straight.

 

I ordered a new MC anyway. When I did the LS1 brake swap about a year ago, the pressure to the passenger side compared to the driver's side was weaker. This translates to a pulling of the car to the right wen I stop. This is just a great excuse to swap it out.

Sway bar. That's what it is.

I replaced the shocks about 3 years ago. How long do they last?

 

This happens to be a lot to. Maybe i should replace mine as well. What kind of MC did you get?

 

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