AustinT

I have a 89 camaro with a 305 it had a t5 in it and a 3.08 rear. I am swapping in a t56 and I want a 3.73 rear gears. I dont care about posi right now. What is the best and cheapest way to get some 3.73's I have been searching the forums and there are not a lot of post on swapping from a 3.08

89BlwnRs

I'd say go for the Richmond 3.73 gear set. They make it for the 2 and 3 series carriers (you'll need the two-series) for around $190.

Jason

AustinT

Do I also need to get one of the install kits they sell. If I remember they are about 100 bucks.

89BlwnRs

If you're gonna have a shop install it you might save some money by buying Richmond's kit. I had a GM dealer install my Richmond 3.73s and Posi-traction and I saved a TON of money (well over $100) just by buying the bearings and all through Richmond and not through the GM dealer.

I went ahead and bought a Richmond Mega Installation kit that includes everything in the Complete kit, plus it has axle bearings. Everything I needed was in the kit, down to the gasket, bolts, bearings, and even the gear marking paint.

Hope this helps,

Jason

AustinT

The guy I bought the car from Just put 1200 into the rearend about a year and a half ago. Im certain it has new bearings already. Can I buy a kit just for the Ring and pinion?

89BlwnRs

If you don't wanna replace all the bearings, I'm pretty sure you can get away with Richmond 1/2 kit, but don't quote me on that one. This comes with the necessary shims, pinion crush sleeve, pinion seal, and the gasket. The kit is $20.99 from Jegs.

Hope this helped, any more questions just ask,

Jason

ryn28

iTrader: (1)

As far as the cheapest way to go, I couldn't really tell you but cheapest isn't always the best. If the rear is coming apart, you might as well have a posi unit installed at the same time, otherwise you'll be paying again later to have the same job done. Even if it means waiting a little longer to have it done, it will be worth it in the end. Not putting the posi in I think is something you'll regret, especially with a 3.73 rear ratio.

82camaro

If you have alot of miles on it, get the full bearing kit(with axle bearings). I would go with the richmond 3.73's for a 2 series carrier. Later on, when you find that your traction is much worse with the 3.73's, you could toss in a powertrax without messing with the 3.73's or the bearings you already put it. I did this swap around 4+ years ago(the gears and the powertrax) and it's way better than the old 3.08 open I had before.

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82 camaro--original steering wheel, brake/gas pedals, seats--everything else modified
82camaro

AustinT

Ok You guys talked me into getting posi. Which one should I go with. The car is my daily driver. Ive been looking though the jegs trying to decide wich way to go That aburn gear Posi looks good but can somebody give me some real world experiences of wich posi is better for the street.

89BlwnRs

I don't have any personal experience with Auburn, but I heard from 2 different speed shops in my area that Auburn makes excellent units.

I do however have experience with the OEM take-off unit from SLP. This is a posi out of a brand new Z28 that SLP was going to turn into an SS for GM. So far this posi has performed flawlessly (although it's only been in for 3 weeks), the lockups are solid, but I haven't been to the track yet. The posi is only for 3 series carriers and 28-spline axles, and has no clutches to wear out like other posis. Best of all, and the main reason why I bought it, was that it was only $99. This posi is made by Zexel-Torsen.

Hope this helps, I can't really base a recommendation on 3 weeks of driving and that fact I haven't really been able to test it on new tires at the drag strip, but so far it's been great. I figured for $99, if it breaks I'd just buy an Auburn,

Jason

[This message has been edited by 89BlwnRs (edited January 30, 2001).]

AustinT

That sounds like it would be a good way to go but dont I have a 2 series carrier I had a 3.08. Too bad

IROC4LIFE

The Auburn posi is on of the best units avaible. With a 3:73 ratio rear end with a T-56 you will really want a posi like auburn or else you will be finding yourself wearing one tire and going sideways lots. Also I have never heard of an Auburn posi buring out its clutches they are extremely tough.

IROC4LIFE

AustinT

Which aburn do I need to get? Is it 109-542041? It says its the 7.5" 10 bolt but it says nothing about Our cars. Im looking in the jegs.

AustinT

Wait a minute I read in the forums that in 89 they went to a 28 spline. Cant I find out if it is a 28 spline and get one of the oem slp take of units that 89BlwnRs was talking about and just buy some 3.73's for a 3 series carrier? Is it as simple as that?

CamaroZ_85

yes it is that simple i was just about to suggest that...it's what i plan to do one of these days

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350, Comp 262, Edelbrock Performer intake 600 cfm carb and exhaust, headers
-JVC, Eclipse, Pioneer, MTX, Phoenix Gold, Planet Audio

AustinT

Can I tell if its a 26 or 28 spline without taking off the cover. What are the chances its a 28 spline

89BlwnRs

Nope, trust me and take the cover off to count for yourself. You'll need to have at least one rear tire off the ground so you can pull the axle out to count the splines. I doubt you could count them in the housing.

A WORD OF WARNING, I have an 89 and when I changed my rear about 3 weeks ago I found I had 26 spline axles, even though all the catalogs says 89s should have 28 spline axles. This is very common! Don't take a chance, just make sure before hand.

A new pair of Moser axles costs $225 plus about $15 for studs and $20 for shipping, I had to do this for my car when I found I had the 26 spline axles and the new ring & pinion was already set-up in the car. When I had the axles installed, they were about .040" over length and I had to have them machined. Moser would not even reimburse me for the $41 machine shop charge. They told me I should have sent them back and they would've cut them to the right size. I simply explained to them that I didn't have time to wait at least another 4 days while my car is sitting up on a lift with the rearend taken apart. The still refused to pay, but oh well.

Furthermore the SLP posi unit doesn't use a crosspin to prevent the c-clips from coming out, it uses a billet block of metal with a groove machine into it for the axle ends to fit into. The Moser axles were bigger in diameter past the c-clip than the stock axles so I had to spend $120 to have that machined down. The extra diameter was put there for strength and is not a bad idea by Moser, had I been using the stock carrier or an Auburn they would have fit perfectly as far as diameter goes, but regardless of the SLP, stock, or Auburn units are concerned, the axles were too long and had to be machined down.

Basically open up your rear and count the splines. If you have 28 spline axles, you can either get the Auburn , Auburn Pro, or SLP posi for it plus whatever 3 series ring and pinion you want.

If you have 28 spline axles, you can get an Auburn, Auburn Pro, or SLP posi and throw them straight in.

If you have 26 spline axles, you can get an Auburn, Auburn Pro without having to by the axles. If you want the SLP and you have 26 spline axles, you're gonna have to buy some new axles to fit it. I'd recommend that if you buy Moser axles that you make sure they're the right length when you order them to save you some trouble. When I ordered they said they had the specs for a thirdgen so I just ordered them, but as stated about, they were about .040" over length. Don't even try Strange Engineering either b/c they told me they don't make axles for the Chevy 10-bolt 7/5"/7.625" rears.

I hope this helps you, if I can clarify anything for you at all just ask, keep in mind you're gonna need to recalibrate your speedo after doing this, and GM makes some speed ratio boxes that work great, but I was not told about when I did the swap. Make sure you check into these, I can even help you a little with them.

Jason

AustinT

Thanks Jason Your post makes perfect sense Im going to count the splines So I will know what i have ahead of me. I bought my t56 today to go in front of this. Its out of a 96 firebird. I still dont know how exactly do do my speedo. Some guys say Cyberdyne some guys say dakota digital and some say go with the cable x. It looks to me like the cheapest way to go is with the cyberdyne or dakota digital.

Thanks again

89BlwnRs

Glad I was making sense, if you need any more help just let me know. Like I said I just did this 3 weeks ago so it's still fresh in my mind, plus I was watching a lot of the time b/c we were having all those problems with the axles.

I got so caught up with your rear and gears I forgot you were swapping a T56. Those ratio boxes I was talkin' about won't work for the T56 if it uses the electronic speedo.

If you need anything, just ask


Jason

AustinT

OH man Ive got 26 spline axles in my 89. I I pulled an axle today and it is 26 spline. The splines are pretty worn so I think I will go to a 28 spline and use the slp posi. What are some good axels I dont want all the problems that 89BlwnRs
had with his new axles. What axels will fit in the slp Posi without any problems?