Difference in 73/87 frame and an 88 frame

[Cilver Beast]

I’m new to Chevy trucks. I’m building a 1986 C10 stepside race truck. After taking bed off, I can see the frame was patched in a few places. The driver side frame rail is lower than passenger side by 1/2 inch. I will have horsepower in this truck and don’t want to mess with this frame. I found a great deal on a 88 frame. I know from 73 to 87 they are pretty much the same. My question is, is the 88 completely different, or just a few things need changed to get my cab and bed on it. The 88 I found is c notched for flip kit, new wheels and tires, gas tank, new brake lines, rebuilt rear end 3.73 posi for $1000. If this 88 frame isn’t even close to fitting, I’m looking for a frame and willing to travel a fair distance if anyone has one or knows someone. I checked craigslist and not finding any solid swb.

 

[CSFJ]

Completely different. They widened the frame rails with the new body style to make room for the fuel tank to be inside them instead of side saddle.

 

[Cilver Beast]

Thanks. Was hoping they were similar. I’ll just keep looking for the right frame. Anyone looking for a 88 frame, look in Cincinnati Craigslist.

 

[bucket]

https://dayton.craigslist.org/pts/d/pemberton-chevy-truck-frame-rolling/6800380339.html

That one even has the proper stepside rear bumper and fillers. Looks like it needs a core support mount and being a 70's frame, you would need to use 70's style cab mounts.

 

[eskimomann209]

Post pics of your frame issue
I can’t see it being an issue with some proper repairs

 

[Rusty Nail]

I think it was 1978 or 1979 the frames were changed (weakened?) to accomodate federally mandated catalyic convertor use, regardless of GVWR.

Something like that happened to some extent and I always considered the PRE-1978 frames to be "better" for no other particular reason.

Hope this helps!

 

[73c20jim]

I have a 73 2wd frame that I don't need.