auto_editor

With the streets around my MI home like skating rinks, I wanted to know if my '89 Custom Cruiser had a limited-slip axle. Per my factory B-Body manual, all I had to do was check my Service Parts ID sticker and see which of the two codes was there and that'd be that.

Or not.

When you have a "GW9" (2.93 ratio) axle, you SHOULD have on your SPI either the "8YA" (standard) or "8YH" (limited-slip) code. Well, it says "GW9" on it but the only "eights" listed are "8DX, 82D, 82I and 829."

[The book also lists axle "six" codes--"6GA, 6GB, 6GM, 6GN, 6GS and 6GT"--for "sedans" but the only "six" on my SPI is "6PS", and it doesn't even SAY what THAT is in the book.]

Adding to the mystery is the fact that I don't have a Monroney for my car, but I have another car's and it lists as part of the "Trailering Package" (which mine doesn't have) a "Rear Axle-3.23 ratio" instead, but it makes no reference to being limited-slip or not.

Is there a way I can find out without crawling under her and try to find the answer directly from the axle itself? I tried the trick of putting one tire on ice and hitting the gas, and it feels like either wheel will spin on its own, but that's not really a definitive answer.

SO, thoughts? I can provide an image--as soon as I figure out how--of the SPI if need be, but the code(s) just plain ain't there.

Thanks in advance,

Drew

monzaz

ALL in the RPO code G80 is POSI / Limited slip option.... ALL RPO codes are in alpha numeric order. Jim

Normally in the glove box or on the spare tire trunk cover some in the center console and drive door jamb.

auto_editor

No, I HAVE the SPI; it's that none of the codes are listed ON it.

[And speaking of code-related mysteries, I even went so far as to try and decode EVERY alphanumeric, and these defied definition (and could be somehow axle related?): "IQD", "1SZ", "6PS" and "7PB".]

This is bringing up horrible memories of Algebra class, but I NEED to "solve for 'X'" on this. SOMEBODY out there has to know...

copper128

If you don't have code G80 on the SPID, it's not a limited-slip rear.
I know on my '95 Roadmaster Estate, the 2.93 limited slip axle was included with the HD trailering package.