Full rear end swap?
 

I want to do a full rear end swap in my 74 C-10. Can someone tell me what rear ends would be a direct bolt up match? I'm guessing 73-87 but would that be the limit without doing surgery?

Thanks!

Re: Full rear end swap?
 

Yes 73-87 half ton 2wd are what you need to look at,Any bigger truck/4x4 will have the wrong lug pattern.And any other years will take welding to fit.

Re: Full rear end swap?
 

That's what I was sort of expecting. Thanks for the reply and for clearing that up. It's a 2WD and I'm going to be hitting the salvage yards soon.

Re: Full rear end swap?
 

Search here, save some gas and time.....

www.car-part.com

Re: Full rear end swap?
 

The 4x4 ones are different lug pattern,But i think if your axle and it are the same you could swap axle shafts and drums.But i have to ask whats wrong with the one you have now ?

Re: Full rear end swap?
 

Nothing wrong with it at all but my comfort speed on the highway is 70-75 and there's a very thirsty 454 turning those 3.73's.

I've had the truck about a month and haven't pulled the cover off but I don't think the carrier will support a 3.42 or 3.08. I could be wrong about that but since I have no experience setting up rear end gears figured it would be easier in the end to swap it with a complete unit - as long as it's a direct fit.

Re: Full rear end swap?
 

Why not pay a shop to re gear it for you ?A used rear axle could be in better shape or pretty much scrap lol.Which trans do you have ?

Re: Full rear end swap?
 

TH-400

I talked to a shop yesterday and was told it could run 4 grand. I don't think they wanted the job.

Re: Full rear end swap?
 

Great link. I didn't know it existed. I'll be up all night :smoke:

Thanks!

Re: Full rear end swap?
 

$4k to install new gears in the rear axle??? Run far away from that shop!

Re: Full rear end swap?
 

:two:

Re: Full rear end swap?
 

4k what are they smoking lol.Talk to other places it should be no where that high.

Re: Full rear end swap?
 

I don't know what they were on either but I 'bout stroked out when I heard the price. Seemed clear enough to me that they either have enough work where they can pick and chose or they just don't want to do rear end work. Maybe they don't have anyone who knows how. Whatever the reason I sure won't be going back. I'd rather be turned away than get low balled or burned by some amateur.

I'm not in a rush to swap. Got a ton of body work and other things to fix right now, but the rear end is on my radar and I wanted to get an idea now so I would know what to look for if I found one locally.

Anyone buy from the list of salvage dealers in the link Warren added? Any "gotchas" to watch for? The nearest goldmine in there looks to be about 168 miles from me, and if the parts are as good as some of them look, it might be best to take a trip and load up with the major body parts I need and grab a rear end while I'm at it.

Re: Full rear end swap?
 

CALL to make sure they still have the parts you are after.
With the axle, ask if you can see the truck its coming out of and I would remove the differential cover and look at the gears to see if everything is ok BEFORE you leave.

Re: Full rear end swap?
 

Yes, thanks. I would certainly want to look inside before handing over the cash. Good tip!

Re: Full rear end swap?
 

You should have 12 bolt from factory 73-81 after there 10 bolts If I remember right.

Re: Full rear end swap?
 

10 bolts were in them since 1973. My 1978 has a 8.6 in it factory

Re: Full rear end swap?
 

Not true. I'm not certain on the year break, but I think it was 77. Earlier trucks had 12 bolts in C10s.

Now we can start the controversy over which is stronger, truck or car 12 bolt. Dont forget 12 bolt vs 10 bolt.

BTW- They shop that quoted 4k probably wasn't too far off average. To do a complete gear change including gears and a locker its commonly priced around 3k or higher.:smoke:

Re: Full rear end swap?
 

my 77 has a 12 bolt, my 80's trucks are all 10 bolt.
gear set + posi + good install kit will run ~800 just in parts. Do you need axles? Brake pads, drums, parking brake parts (there's a difference in park brake cables somewhere in there..)? Looking for a disc conversion? And since the drive shaft is out, it's a good time to do U joints, and a center carrier if 2 piece, and that rear trans seal and trans mount.

If you do put in a 10 bolt you will need a conversion U joint (not expensive).
While 4k seems a little silly, certainly $2000-2500 to have someone build one is not out of line.
The posi is the expensive part, but good bearings add up.
Also think about brakes, if it's a factory big block you may have the large brakes, and a lower geared axle may not. You would have to switch backing plates or live with lighter brakes, which really wants a different master cylinder.
Before you do this, sit down and calculate how much gas you'd be saving. Unless you get the axle dirt cheap it usually cost more then you would save.

Re: Full rear end swap?
 

12 bolts through '81. 10 bolts started in '82.