My72Cutlass

Where should I b looking, if im interested in a used 12 bolt rear end, inexpensive that is..... again I'm looking for a 12 bolt rear end 373???? any help in pointing me in the right direction would help... Thanks Guys this site is amaizing for us first timer's!!!!

RetroRanger

craigslist, here, swap meets, etc. any 68-72 A body GM (chevy buick pontiac olds) rear will fit your car there are some differences tho...most anything chevy is different in some ways from olds

FYI your 72 came w a 10 bolt rear

My72Cutlass

Yes my 72 did come with a 10 bolt, with what im trying to do I have been told I need to find a 12 bolt rear end to than make it a pose tracktion and with the gears to b 373..... I have a 350 engine and want more horsepower out of it, so I will b boreing it aswel.... any feed bck to help me would b great, again this is my first attempt at restoring a classic, I have never really done any work on cars other than change out a water pump...lol so I do need some helpful advice..... Thanks RetroRanger!!!!

joe_padavano

For an "inexpensive 12-bolt", you should be looking in the 1970s. ALL A-body 12-bolt axles, especially desirable ratios with posi, go for stupid money today.

ALSO, be sure you can tell the difference between a Chevy 12-bolt (which is what I assume you're looking for) and a Type O axle. The Type O also has 12 bolts on the cover but only 10 bolts holding an 8.5" ring gear (same as your current 10 bolt axle). The Chevy 12 bolt has 12 bolts holding an 8.875" ring gear. Most sellers call the Type O a 12 bolt, either out of ignorance or deceit.

droptopron

Keep in mind, unless you are doing something really nuts a 10 bolt can be built up to handle lots of power just fine.
For parts availability a Chevy rear end is preferred. Keep an eye on your local CList. As far as getting one cheap, how cheap is cheap? You get what you pay for & you gotta pay to play.

My72Cutlass

Thanks guys, and yes I do know what you mean by pay to play.... And I do want to play!!!!! I will have to check more into my 10 bolt that I have as to if its a chevy rear end or what I actually have..... I dont know a whole lot about what I'm doing thats why I'm asking alot of these dumb questions..... You guys are great!!!!!! Thanks for all the help!!!!

RetroRanger

You could upgrade your current rear end w new gears and an eaton posi unit, IDK if 3.73 gears are available for the 10 bolt. The eaton unit is about $500.

My72Cutlass

Ok will check into that!!!! Thanks