78 C10 Rear End Help
 

Hello all, I am in need of some knowledge!

A buddy of mine has a short bed 78 c10, it is what some might call a one wheel wonder lol

Can any of you give me any more information on the rear end in this truck?
Are there any Posi units or lockers compatible?

It has seen better days but still has good bones, so we were throwing around the idea of taking it off the road and turning it into a drag truck of sorts.

If any of you have experience building these trucks to drag I wouldn't mind hearing anything you had to say about that either, but my primary questions are about the rear.

Thanks!

Re: 78 C10 Rear End Help
 

The rear should be a 12 bolt truck rear. Cant tell you gear ratio but that's easy to figure out on your own. Just pull the cover and either count the teeth on the ring and pinion then divide or look for the stamp on the ring gear. There are plenty of options for posis and lockers. I prefer an eaton clutch type posi especially on anything street driven. Lockers can be rough on the street.

Plenty of these trucks being drag raced. The leaf springs in back leave a lot to be desired when it comes to traction. Cal trac bars can do wonders though.

Re: 78 C10 Rear End Help
 

If you are just going to thrash it and drag it then all you need is a Lincoln locker (welded).
I'm sure there are lots of how to articles and videos out there showing how it's done.

Re: 78 C10 Rear End Help
 

Good info! And do those Lincoln lockers really hold up??

Re: 78 C10 Rear End Help
 

I would go with a spool or mini spool before I would do a 'Lincoln Locker' (welding the spider gears). When those come apart it isn't pretty. And you can be assured it will come apart sooner or later.

An Eaton clutch style posi would be best for a street/strip truck, or a Detroit locker for a mainly strip with a little street truck. Or if strictly strip a spool as I mentioned above.

Re: 78 C10 Rear End Help
 

Do you think I could find a salvageable posi unit In a junkyard somewhere? A locker would be better I think but I am not sure if I could find one of those in a junkyard.

What type of truck would I be looking for that could have this?

Thanks

Re: 78 C10 Rear End Help
 

It will be a wild goose chase. Most of the 12 bolts didn't have a posi factory in trucks. The trucks from I think 80 and up all had 10 bolt rears and the posi in them is not compatible with the 12 bolt and its also a turd. They are known as gov-bombs. Proper name is a gov lock but they tend to explode fairly easily especially when you thrash them. Your probably going to be stuck buying a new unit.