"Shadowfax" - Jeremy's 15th Anv. Trans Am

[DynoDave]

.. but was wondering your guys thoughts on swapping in a 4th gen rear end? found a posi unit with 3.42 gears with disc brakes for sale...

My understanding is the '98 and newer units have the much stronger Torsen style differential, as well as the stronger 28 spline axles. Between these stronger components, 3.42 gears, and discs, the ONLY draw back (if you consider it one) is the extra axle assembly width.

[C2YT]

Darren is right! You can't run thirdgen wheels.

Well I guess you could if you really wanted to but we would all judge you.

[hoogiesngrinderz]

Just to clarify, 99 and up came with the Torsen style differential if it was a G80 or Y87 car. 98 still had the cone style Auburn. They are 28 spline vs the 26 spline that came in the older third gens. Late 1989 and all 90-92 rears got the 28 spline axles.

[DynoDave]

Just to clarify, 99 and up came with the Torsen style differential if it was a G80 or Y87 car. 98 still had the cone style Auburn.

Thank you for clarifying that!

[Jdseibe]

thanks guys! I think if the rear end is bad in my car that I will either try and fix (depending on how severe it is) or just swap for a later year 3rd gen rear.. retaining the ability to use the stock wheels is something that I would like to have considering this is kind of a unique car. I'll keep everyone updated!

-Jeremy

[Jdseibe]

So nothing looks broke and seems to spin fine.. I spin one tire and the other spins opposite direction.. Anything I should check while the cover is off?

uploadfromtaptalk1429915865263.jpg

[Jdseibe]

Just kidding....

uploadfromtaptalk1429918283998.jpg

[C2YT]

Well sir, I think you found the problem!

[Jdseibe]

so my car is a 10 bolt with a stage 3 carrier with 26 spline axles...

I now need an affordable ring/pinion set 3.73 is what I would want to go with. and an install kit.. can anyone give any recommendations? I've never done a rear end so this is new territory for me.

[Jdseibe]

http://www.ebay.com/itm/3-73-RING-AN...90b5f2&vxp=mtr

would something like this work? does it being 26 spline make any differences with the swap?

[Jdseibe]

anybody? ^ Im just tagging a bunch of people to see if anyone has any direction for me to go.. [MENTION=2135]bigjon88[/MENTION] [MENTION=1366]MP81[/MENTION] [MENTION=1993]Darren[/MENTION] [MENTION=3597]ruckusz28[/MENTION] [MENTION=2608]Gregs_gsxr[/MENTION] [MENTION=1515]92conv[/MENTION]

[bigjon88]

Find a new rear it would be cheaper

[Jdseibe]

so after doing a little looking around and some research I decided to just go ahead and do the gear swap vs swapping rears.. swapping rear is the easier solution, but in all reality I am still buying something that is used and may also be on its last leg.. plus I would like to stay with a third gen rear and 3.73 gears.. so that makes it even harder to get a hold of. my brother is a certified master mechanic so he offered to help me do the install. I ended up ordering a Motive gear set and install kit for it.. got it on a deal for around $200. I'll keep everyone updated on the progress.

[hoogiesngrinderz]

Just be sure to get it set right and take your time during break in. Not giving it enough time to face harden before getting on the throttle will cause gear whine. Sometimes gears new gears are noisy regardless, AAM are typically the quietest gears because of their manufacturing process.

[C2YT]

If you need some moral support when you are doing the swap, i volunteer to be tool boy!