daytonayellaz

iTrader: (13)

I need some help here guys.... I always thought these rears were all the same in the LS1 cars? I know a V6 car is not a LS1 car but usually everyone refers to the 98-02's as being LS1 cars.

The guy at the salvage yard today tells me that his computer says the rearends are not the same...He has a 99 V6 firebird with the G80(posi) and GU6 (3:42) disk brake rearend which is exactly what I want.

Sooo.. Is there a difference between a 99 firebird LS1 rear and a 99 firebird V6 rear? (Of course other than the ABS and TC.)

Also....What about driveshafts? Are there differences in these and if so what are they?

Thanks in advance!

Travis

01ssreda4

iTrader: (96)

as far as I know they both have ten bolts. Only difference would be where the speed sensors are for tcs and abs and the backing plates for the brakes. Everything else should be the same except no posi in V6 models and I dunno what gearing they came with stock.

daytonayellaz

iTrader: (13)

Well this is a V6 car.... I called GM service dept. and gave them the vin# for the car and they pulled up the RPO codes and said it has the G80 and GU6 (posi with 3:42) options.

What is the difference in the brakes? This one has disks, do V6 cars have smaller disks or calipers? What is different about the backing plates?

01ssreda4

iTrader: (96)

I would think brakes on the V6 would be smaller. If you are not sure pull up part numbers on a parts store website and verify part numbers for v6 and v8 models and see if rotors and stuff use the same part. I personally have never worked on a V6 rear end so i have no idea whats there. At any rate there should only be slight variations as the housings are the same.

venom99

iTrader: (32)

the are the same minus the gears in them

daytonayellaz

iTrader: (13)

Do you mean a 3:42 V6 car has different gears than a 3:42 V8 car?

11SECSS

iTrader: (199)

I think the rears are the same . I installed a v6 rear in my SS when I broke mine a while back and they where the same. Some of the v6 car came with posi and some even came with 3.08 gears.

daytonayellaz

iTrader: (13)

OK....Good. This rear is in a V6 car and is a 3:42 posi.

Know anything about the driveshafts?

SparkyJJO

iTrader: (11)

Lucky you. Most V6 had 3:08 with no posi, or 3.23 if using the manual. The brakes on the 98-up are the same on all 4 corners as the LS1.

It should bolt right up. the driveshafts are the same I believe. The majority of V6s had no TCS so keep that in mind.

I wish my V6 had a posi but it has an open diff 3.08, and being a series 2 it is hard to find a series 2 torsen unit

venom99

iTrader: (32)

no i mean the gears are diff in general in the ten bolts auto to manual but the v6 rear is the same as the v8 rear

daytonayellaz

iTrader: (13)

I kinda thought thats what you meant, just wanted to be sure.

Thanks for your help.

daytonayellaz

iTrader: (13)

I called 2 different GM Service/Parts dept. and gave them each the vin# on the car just to be sure I received the same info. and they both said GU6 and G80.

I dont need the TCS, so Im good on that front. Are the disk brakes the same on a V6 vs LS1?