CC 2wd to 4wd

[Mattman2010]

I have ran into some problems with converting my CC C30 dually 2wd to a 3/4 ton 4wd. All of the 4wd parts that I am using are coming off of a 1980 k20, my CC c30 is a 1985 and I know some things are different between the years. None of the k20 spring mounting brackets on the frame swap directly over to the C30, I have had to drill new holes for the swap from the dana 70 to the Corp 14b. I am starting to swap in the front axle and have noticed that none of the bolts line up for the front leaf spring/core support mount. The k20 engine cross member does not fit into the C30 frame rails. Now that you are probably confused with all this rambling, here is my question.

Would it be best if I found a 81 - 87 k20 frame to get parts to convert the c30 to 4wd? Or is my problem that I need to find a K30 cross member to put into my c30? Or am I going to have to go buy some steel and make my own cross member?

Thanks, Matt

[LONGHAIR]

I think you are running into issues for multiple reasons, but I don't think that the year difference is one of them.
1 ton frames have differences, not the least of which is height of the rails themselves. So none of the crossmembers from 3/4 ton trucks are going to be a direct fit.
The other is with "engine" crossmembers....On a 2 wheel drive truck, the entire front suspension and the engine "stands" bolt onto the frame as a crossmember. With a factory built 4x4, that is not the case at all. The springs themselves are the mounting points and there really is no crossmember for the engine at all. There are engine mounts on each side, but nothing ties them together.

[Mattman2010]

Do you have a picture of a 1 ton 4x4 engine bay so I can see what you are talking about? Both my 80 k10 and 80 k20 they have the engine mounts that bolt inside the frame rails, and then there is a cross member that goes in the front of them that holds them together.

[GM72K10]

Maybe this will help. Here's a picture of the frame under my K30 dually pickup. Note the place for the engine mounts. FYI this frame started out as a CUCV (all 1 ton frames are the same whether dually or single wheel, from cab up) ambulance frame, single wheel. The crossmember for the trans/transfer case is not in yet.

[Mattman2010]

That is exactly like the one that I pulled off of my k20 frame to do the 4x4 swap onto the Crew cab. The thing is that the parts with the actual mounts on them will not slide between the rails. They are to tall compared to the frame. I am also using 80 style front spring/core support mounts which are different than the ones on your frame, but as long as I use 80's style mounting bushings on there it should be fine.

I guess I could cut the mounts up and make them fit. Could you measure the height of the drivers side engine mounting block on the rear part of it (the part that is inside of the top and bottom rail of the frame)? I am not sure if I really explained that very well.

[GM72K10]

Here's the frame I started with

[GM72K10]

K20 frame is going to be a different size than the K30 frame.

[b454rat]

I did the same thing to my 89 crew cab. Was a2wd dually now a 4wd SRW. Like you found out already, a 4wd engine crossmember doesn't fit. I had one from a 1/2 and a 1 ton, both are the same, of course neither fit.

I used DIY4X B-52 kit to mount the front springs. If you call him, he can make them for standard width bushings, but are made 3" wide. I used stock length 48" springs, just cut the bushing down 1/2" overall.

As for the engine crossmember and mounts, I used the 2wd engine mounts and boxed them in similar to what 4wd mounts look like. Then just get a piece of DOM or tubing to make a crossmember to tie the frame together.

I think I still have the link in my sig, there is some pics of my crew in there that shows the mounts.

[Mattman2010]

This is what I have


So I guess the only thing I can do is either find a k30 frame (Cant find any lately), modify the k20 cross member/engine mounts, or make my own cross member.

[Mattman2010]

b454rat, I looked at your pictures and saw a few on the 2wd engine mounts, but I never did see a cross member between them. Did you build a cross member, or how did you go about doing it? All I saw was a bunch of pictures of them but nothing that seemed to hold the bottom or any sort of support besides the two top bolts.

[b454rat]

Hmm, guess I didn't get any pics of it yet. But I used Tennessee Diesel Conversions Cummins crossmember since the truck will be getting one in the future. But just something to tie the frames together will work.

[Mattman2010]

After rereading your post b454rat I feel retarded, you didn't say you made a cross member and gave a suggestion on how to do it. I guess I will have to buy some steel, but I am not sure of a good steel place around here.

How did you drill the hole for the shackles on the front axle in the rear? isnt that like a 2 inch hole? How did you figure out where to mount it with there not being all of the weight on the front?

[Mattman2010]

So as long as the mounts can support the weight of the engine, they will be fine, and all I need to do is keep the frame from spreading apart in that area right there?

[b454rat]

I used stock length front springs, just marked back 46" so, and get a 2" holesaw and went to town. Keep it clean and cool with some oil or WD-40. Only took maybe a minute to drill a hole.

Also didn't have a motor/tranny when I drilled the holes, nor front clip or bed.....

[Mattman2010]

What did you do for the front sway bar?

[b454rat]

Not gonna run one. I haven't ran a front sway bar on any of my trucks in years.

[Ford Assassin]

Digging up an old thread....

Originally Posted by b454rat

I used DIY4X B-52 kit to mount the front springs. If you call him, he can make them for standard width bushings, but are made 3" wide. I used stock length 48" springs, just cut the bushing down 1/2" overall.

Did you use stock bumper brackets with the B-52 kit?

Thx.

[Dieselwrencher]

Originally Posted by Ford Assassin

Digging up an old thread....




Did you use stock bumper brackets with the B-52 kit?

Thx.

He hasn't been on here in years but I could ask him for you.

[Ford Assassin]

Originally Posted by Dieselwrencher

He hasn't been on here in years but I could ask him for you.

Please do.