Any difference between C10 & C20 Rearends?

[D-n-Tyke]

Follow up to my other post in regards to front end differences. Thanks again for those reponses.

Now I am trying to figure out if there are any differences between a C10 and C20 rearend (other that the bolt pattern in the axle flange and drums) . Trying to convert from 8 lug to 5 lug. I know I can buy the conversion kit that comes with new axles and new drums, but I might have access to a 1970 C10 rearend. So if they are the same I think swapping the rear end might just be the easier.

[TurboThrift]

Hey there,

A C20 rearend is way different than what is found on a C10. The C20's will have a full floater 8 lug setup, either a Corporate HO52 or Dana 60. As far as I know, there is no aftermarket 5 lug conversion drums, axles, etc. for the axles mentioned above.

[D-n-Tyke]

This was one of the kits I was looking at (although looking closer looks like it is for 6lug to 5 lug).
http://https://www.speedwaymotors.co...RoCAOsQAvD_BwE

Okay with that said, is that the only option I have to go from 8 lug to 5 lug is to swap the whole rear end?

[TurboThrift]

Yes, that is correct. I'm sure you can find a donor 12 bolt diff from a 71-72 C10. Or if that isn't possible, a 6 lug to 5 lug swap (as you referenced) is fairly common.

On a side note, are you switching to 5 lug for wheel selection or for disc brakes?

[D-n-Tyke]

Originally Posted by TurboThrift

Yes, that is correct. I'm sure you can find a donor 12 bolt diff from a 71-72 C10. Or if that isn't possible, a 6 lug to 5 lug swap (as you referenced) is fairly common.

On a side note, are you switching to 5 lug for wheel selection or for disc brakes?

So I have a potential lead on a 71 C10 "complete" front suspension (crossmember included) with with disk brakes and a complete rear axle from the same truck. I will have to see how much the guy is willing to deal. I think he might be asking a bit much right now at $700 (rear axle comes with trailing arms, springs and back half of the frame).

Yes, I am looking to switch from 8 lug to 5 kug for both reasons. Want disk breaks and I want to have some options for wheels.

Question for after I do this conversion. Are these C20 rearends in much demand?

[TurboThrift]

I see. That sounds like a nice package deal if he's willing to negotiate.

And there is some value in that rear end, although it's a niche market. Finding good used 8 lug rears of this vintage is getting tough. Does yours have a locker/"No-Spin" unit?

[D-n-Tyke]

Originally Posted by TurboThrift

I see. That sounds like a nice package deal if he's willing to negotiate.

And there is some value in that rear end, although it's a niche market. Finding good used 8 lug rears of this vintage is getting tough. Does yours have a locker/"No-Spin" unit?

Let's hope he is willing to negotiate. Make my life a lot easier with this conversion.

I am not sure if it has a locker or not (just pick this up a couple weeks ago). Would it be listed on the SPID? I will have to go out and look and see if I can find a tag on the rearend.

[Accelo]

Would it be listed on the SPID?
Yes....
However, things may have been switched out over the last 50 years.

[Big Kev-O]

Originally Posted by D-n-Tyke

Question for after I do this conversion. Are these C20 rearends in much demand?

You may be able to get a couple hundred $ for you 8 lug depending on the gear ratio and type but it could be a while before you find a buyer. My friend gave me a Eaton axle off his trailing arm truck and I posted it on Craigslist for free, luckily nobody picked it up because I removed the 4:10 Ring & Pinion and sold it on this website for $375. It sold a couple days after I listed it. Parts are not available for the Eatons so if you have the right gear ratio it can be worth some money.

[SkidmoreGarage]

I was just barely able to give away a good Eaton 4.56 from a C20. I also sold a C20 Dana 60 3.56 (somewhere around that ratio) for $600.

The Eaton stuff just isn't available, or cheap, so the market is very small.

[TurboThrift]

I agree with the posters above. Your best bet is to post your old diff in the parts section and see what offers you get, you may be surprised.

[D-n-Tyke]

Well the front suspension was sold before I could get there. But I did end up picking up the rear end, actually it was the whole back half of the frame (arms and springs) cut just forward of the trailing arm crossmember, and a set of steel wheels and tires. The whole shebang for $300. Figure not a smoking deal but one I could live with.

Now on to the hunt for a front suspension.

[special-K]

Rears go in the $300 range. You did fine. You also have the extra parts to sell. The '70 rear is the last 6-lug but is the same width as the '71-ups. The rears got widened when disc brakes came out. You are all set. So this rear has been converted to 5-lug?

[D-n-Tyke]

Originally Posted by special-K

So this rear has been converted to 5-lug?

I was told the donor truck was a 1971 so it was already 5-lug.

[Big Kev-O]

You did excellent, a good set of trailing arms go for at least $250.

[D-n-Tyke]

Originally Posted by Big Kev-O

You did excellent, a good set of trailing arms go for at least $250.

That is good to hear. I kept the trailing arms and the trailing arm mounting crossmember (with mounts). Going to junk the rest of the "half" frame as I assume all the other crossmembers are common and not worth anything.