how to go about this?

[slavejay]

how would i go about changing the ratio of the rear axle? what parts would i need to replace and off of what kinda car? i own a 85 caprice 305. i hope my questions clear because i just read it over and it might be kinda confusing?

[silicon212]

Basically, you just simply change the pinion and ring gears in the differential.

[slavejay]

Originally Posted by silicon212

Basically, you just simply change the pinion and ring gears in the differential.

what year / make car would the pinion / ring gears come out of?

[silicon212]

You have to do some research on what you have. Likely you have a 7'5" ring gear knowing what you have, but you can verify this by looking at the SPID information. Up to '84, the SPID information was on a paper attached to the top of the gas tank (you have to drop the tank to see) but beginning in '84 they moved this information to a sticker on the underside of the deck lid (Service Parts Identification - DO NOT REMOVE) - you want to see what 3-character alphanumeric identifier you have that starts with a "G" (i.e. G80, GU4 etc). Post what you have here. G80 is limited slip (Positraction) and I believe these were all 8.5" but I could be wrong.