3100 frame lengthened to 3600 specs. Anybody done it??

[Coach529]

Casually shopping for a 3600 chassis for Henry. I would like to build it up with IFS and IRS on bags and once I get it all built do a body swap.

I have not been looking very hard, but have not come up with anything local.

Then I got to thinking. I have a 3100 parts truck. There is not much left of it. Missing doors, body work is rough........etc. But the chassis is there.

So could shorten my box, but I would much rather stay with a long box. Or lengthen the 3100 frame 9-1/4".

Has anybody done this?

[mr48chev]

I'd post an add on the local Craigslist offering to trade bare frame for bare frame first. GMC built half tons with long wheelbase frames that have the same spread in the back as Chevy 3100 frames. That is what this is as I am going to lengthen my Chevy cab 9-1/4 inches and use the 3100 box.

[Hampshire]

Having shortened a 3/4 ton frame, I thought I would chime in...

Many have pointed out the flexing inherent in these old AD frames. One attribute the 3/4 ton frame has that I like is that the metal is 3/16" thick as opposed to 9/64" on the 1/2 ton - that's almost .050. That helps, but alone may not do it, so we boxed areas and will probably add an X-member. I think this would be even more important using a "lighter" 1/2 ton frame.

I suppose you could lengthen the frame by adding 9-1/4" in the same place you would cut a 3/4 ton frame (right behind the cab). I can see some pluses: The wider frame at the back and the arch makes it easier to lower than a 3/4 ton. You also get an arched cross member that allows a spare to be mounted underneath.

[72JimmyDiesel]

3100 frame tapers from front to back unlike the 3600 frame. it is wider in the rear.

[whitedog76]

Yes, the 3100 frame is tapered all the way back.

The 3600 frame is tapered in the front, but staightens out about the middle of the cab all the way back.

Your best bet is finding a 3600 chassis, or a custom chassis.

[T Hilde]

I don't know what superfly did with my 3600 chassis, it had that damforth kit on it. Last I saw it was on a trailer heading towards Roseau about 5 years ago.

[Coach529]

Originally Posted by T Hilde

I don't know what superfly did with my 3600 chassis, it had that damforth kit on it. Last I saw it was on a trailer heading towards Roseau about 5 years ago.

Interesting.......might have to contact him.....

[Apachemike]

There were a few long beds for sale near Atlanta not long ago.