I would like to know so that i can by one of those slp torsen carriers. And if i did would a 3.42:1 ratio work on one of those, that is three series carrier isnt it???thank you

 

They started in 88, but the change wasn't complete until 90. 89 up also got the good disk brakes which don't require any changes to the hydraulics except dealing with the metric vs. std lines, unlike the older sisk system which doesn't work very well and uses different hydraulics.

Yes, the 3.42 gear will go right on the 3 series carrier which is what the SLP unit is.

 

thanks for the help man

 

so does only the 89's with disk brakes in the rear have 28 spline. i have a 89RS with drums in the back and wanted to buy the SLP posi.

 

AFAIK, it's a throw of the dice whether or not a specific 89 got the 28 splines or not. 89 was the changeover year, and some got 'em and some didn't.

 

so how do i find out how many i have

 

hjyuvgfyi

 

ok that helps

 

Pull an axle and count the splines.

 

That's what I was going to say above but couldn't find a polite way to word it. (how else could a person figure out their axle spline count)

 

It's the best way. You could go through all this discussion only to find out a previous owner swapped an older rear end in and you have 26 spline axles. That happened on a 91 that I was going to grab the rear out of. Pulled the axle, counted the splines (like 5 times), and, hmmm... only 26...

 

so is it only 26 and 28, cuz ive read places that said 27 and 30 splines.

 

do i have to take the whole axle out or could i just take off the diff cover and count

 

I think 27 and 30 refer to the splines in the 700R4 transmission.

 

it's also the pinion spline count for the 7.5 and 7.625 rears (27) and the 8.5 GM rears (30).
You have to pull the rear cover off, the cross pin retaining bolt, the cross pin, one wheel and brake drum to remove an axle. You can always get a used set of 28 spline axles to go with the torsen if you find out you have 26 spline axles.

 

The AUBURN web page says that it started in '89, and I have an '89, so i bought a posi and everything, got it all near installed, and it turned out that mine has 26 spline axles.......so i'd have to say 90, cause my '89 has 26 spline axles.

 

My belief is the change happened in 1990. All 9-bolts already have 28 spline axles, so we're talking 10-bolts here. Every 88 and 89 car I have seen and heard about on here with a 10-bolt has 26 spline axles. For the 1990 and up cars, GM dropped the 9-bolt and went with the 10-bolt on everything. They also upgraded them to 28 spline axles. But your results may vary, as there's an exception to every rule.

 

how do i take my axle out to count. or can i just count from the diff cover

 

also didn't the revision of the tranny come with the 28 splines and a auxilary valve body. cuz mine has it so would i also have the new axle.

 

Aux. valvebodies started in 1987.

 

Could somebody please post a pic of a nine bolt, i've never really seen one and am wondering what they look like compared to a ten bolt.

Thanks

 

Imagine a rear end with a cover with 9 bolts holding it on.

That's what a 9-bolt looks like.

 

would a chevy dealer be able to tell me if i told him my vin.

 

The transmission input spline count has no effect on the rear end axle spline count.

And no, I doubt the dealer would know. You have to pull apart your rear end and count the splines on the axles. Its a complicated process.

 

its complicated to pull the axle out?

where is this pin and stuff to pull out.