Rear Frame Crossmembers. All the same between long box?

[rcb1]

For rear cross members, will they all be the same between 1/2 ton, 3/4 ton and 1 ton? All of my crossmembers after the cab are rotted and need replaced. Since so many GMT400s are rotted out, I may have to take what I can find. They aren't load bearing per se, but figured I would ask.

 

[evilunclegrimace]

I will go out and measure my 88 K 3500 and my 90 K 1500 and I'll let you know what I find

 

[evilunclegrimace]

I measured My 3500 and one of my 1500's and I have approx 4 1/4" on the inside of both rear frame rails That is measure inner flange to inner flange. The GM parts catalog shows different part numbers for 2wd to 4wd and from 1500/2500 to 3500.May be some one else has more info.

 

[rcb1]

I measured My 3500 and one of my 1500's and I have approx 4 1/4" on the inside of both rear frame rails That is measure inner flange to inner flange. The GM parts catalog shows different part numbers for 2wd to 4wd and from 1500/2500 to 3500.May be some one else has more info.

Thanks! That's more info than I had previously. I'm just glad it had the gooseneck mount welded in. I think it helped hold everything together.