Pops 1970 C20 Suburban
 

I just bought this C20 Suburban in the hopes of using it as a daily driver. It was redone in 2003 and then parked for 10 years. It's got the factory 396 (402) and a Turbo 400 tranny.

I want to convert it to a 1/2ton and I'm leaning towards going with 6 lug instead of 5. The donor rear axle I have is 6 lug and I wouldn't mind running 6 lug GM rally wheels on it.

So since I want disc brakes in the front, but with 6 lug rotors, can I piece that together with stock parts instead of ordering the kit? I know some 1992 Chevy 2500 2wd trucks came with 6 lug instead of 8, just wondering if I could use those rotors on a spindle that would work with my control arms, or do need to change control arms too, or am I better off just buying a kit? I'm thinking of doing about a 3" drop on the front, but don't want 3" drop spindles if my 15" rims will hit them. Maybe a 2" spindle and cut a loop off the coil..

Re: Pops 1970 C20 Suburban
 

Crusty ol big block..

Re: Pops 1970 C20 Suburban
 

There was a huge chunk of bondo missing from the tailgate, so I spent a few hours grinding it down to bare metal..

Re: Pops 1970 C20 Suburban
 

I tried to piece it together and finally gave up and bought the rotors from CCP. The problems I ran into with the light 3/4 rotors is the offset on the spindle kept the caliper from fitting over correctly. plus I think the seal didn't work either.

Re: Pops 1970 C20 Suburban
 

I'm not 100% set on 6 lug. I could do 5 lug too

Re: Pops 1970 C20 Suburban
 

I think if you're going to go to 1/2 ton with discs it would be easiest to go 5 lug and use stock parts. It's easier to convert the rear diff to 5 lug than try to piece 6 lug discs. Let alone when you need to replace something you can get the parts at a parts store instead of online order to get parts

Re: Pops 1970 C20 Suburban
 

Is it easy to swap my rear half ton 6 lug axles to 5 lug?

Re: Pops 1970 C20 Suburban
 

Ok! New development! My buddy Dave, (72LOBURB) is giving me a 5 lug rear diff for free. So I'm now heading in the 5 lug direction for the front end 1/2 ton disc brake conversion.
I may have a line on an 86 GMC 1/2 ton 2wd parts truck. Can I use the 1986 control arms without changing the whole C20 crossmember?

Re: Pops 1970 C20 Suburban
 

yes.

Re: Pops 1970 C20 Suburban
 

Based on my experience, I also highly recommend leaving the original crossmember.

Re: Pops 1970 C20 Suburban
 

This make me happy

Re: Pops 1970 C20 Suburban
 

I have no desire to remove the crossmember if I don't have to. Do you guys know if I have to change both upper and lower control arms to make the 86 style spindles work?

Re: Pops 1970 C20 Suburban
 

That would be the easiest.
You can reuse the original upper a-arms,... but you would have to swap in 73-87 1/2-ton balljoints.
So use the '86 a-arms.
(they also have rubber bushings instead of steel cross-shaft bushings)

Lowers definitely have to be swapped.
C20 lowers have a bigger balljoint hole in them,... than the C10 version.

Also use all the steering linkage from the '86.

Re: Pops 1970 C20 Suburban
 

This helps a lot! Thank you so much!

Re: Pops 1970 C20 Suburban
 

Picked up my donor "truck" for my 1/2 ton rear diff. (71-72 GMC with a 12 bolt)

Re: Pops 1970 C20 Suburban
 

And my $500 disc brake donor truck! Also happens to come with a 305 that runs great and a 700R4 that I'll keep for a different project.