ok i am sure that this has been answered before but i cant find where...
I have an 87 TA that is fully loaded (5.7, all wheel disks, etc...), how do i tell if it is a 9, 10, or 12 bolt rear end? what is the difference anway? i here all this stuff about them and i really have no clue what is different between them. also is there anyway to find out what gears i am running?

thanks
mcwille

 

The way that you can tell if you have a 9, 10, or 12 bolt is to get under your car and count how many bolts are holding your rearend cover on. and for gears.. there should be a tag under one of the bolts that should have stamped on it what gears you have. If your tag is missing. you can check your RPO codes and find out that way. or you can just pull the cover and look.

 

only way to know what gears you have is to pull the cover and do the math.

 

i dont have my RPO sheet i really wish i did and counting the bolt WILL tell me what rear end i have someone told me that that isn't what make it a 9 or 10 bolt

 

someone lied to you, or just didn't know any better, counting the bolts is how you tell.

 

You can also tell if it is a 10 bolt what ratio is in it by looking at the stamped code on the axle housing on the front drivers side I think or maybe the passenger, but its on the front...
If it is a 9bolt its on a tag bolted to the rear cover.

 

Only if nobody has changed the gears. The only way to tell for sure is to take the cover off and look. This is also a good opportunity to change what very well could be the factory original lube.