‘79 C70 front bodywork on to a ‘77 C30 crew cab

[wbmoore]

Does anyone have firsthand knowledge of installing a 1979 C/70 front clip on to a 1977 C/30 crew cab body ??? There are many internet photos of this combination on C/70 chassis and even some that appeared to be on C/30 frames. I know some of these were made for railroad companies, etc.... were these after market or GM factory built ???
Not wondering about the frame fitment ....just wondering about the front clip to the crew cab problems.
Per usual, answers saying Can Do and No Way are easily found on the InterWeb.
Thanks.

[txagincali]

I don't have any firsthand knowledge on these but have some experience on the 67-72 style which may or may not directly translate to the 73+ body styles.

The short answer is yes they can fit and should bolt in no problem at least cowl to fender-wise just fine.

The big issue you are going to run into is with grafting the medium duty front end to the light duty body (assuming you are using the light duty chassis) is that the medium duty fenders and hood are significantly shorter than the light duty parts. There would be a need for significant fabricating to make it fit/let alone lining up the wheel in the wheel well.

A smaller issue, but an issue nonetheless, is that the fenders and fender extensions cut into the lower corner of the door. This is in part to make way for the larger wheel/tires but also the inner fenders connect underneath the kick panels and actually cut into the firewall some for clearance. Now with those pics you posted, they don't look to be AS bad as the 67-72 but still something you should think about when going in.

Are you running the C30 frame and wanting to just install the C70 nose? Or are you swapping the C30 crew cab body onto the C70 frame?

[wbmoore]

Here’s the deal: I have a 1982 2WD C/30 crew cab frame and a 1977 crew cab body. I’m installing a Cummins 12v w/NV5600 in it. It’s being built to tow a fifth-wheel. It might be easier to lift the body rather than cut the firewall/trans cover. If I lift the body, it would be appropriate to add the C/70 front clip if the 12v will fit. I just bought the C7000 fire truck above for the water pumps .....so the bodywork could be used on the crew cab. I could possibly use the C70 frame (haven’t measured it yet) except the insurance might be a bunch higher.

[jumpsoffrock]

Not that it's any of my business but will it pass smog?

Very interesting build nonetheless.

[wbmoore]

....jumps off rocks: the 1982 C/30 frame was originally a GM 6.2 diesel so should be okay.
Has anyone put a C7000 front clip on a C/30 cab ???

[txagincali]

I think you would be better off keeping the C70 chassis and front clip and swapping the crew cab body onto it. The front body mounts will line right up, the rears will just have to be fabricated. Then you know the front end will mate up and you won't have to mess with wheel alignment in the wheel well. But you'd be stuck with the weight and HD axles that probably won't go too quickly.

If you put the C70 front clip on a C30 chassis, you will have 4-6 inches of frame sticking out in front of the grille. then you'd have to move everything back (axle, spring perches, steering etc.) Check out the Duke by RTech. He managed to squeeze a 12v Cummins into the engine bay of a C50 but I think a decent amount of fab work was needed since you are shortening the space it can fit with shorter fenders and bigger rad.