wondering if anyone has ever attempted this? the body on my 99 (unknown to me) has rusted away pretty substantionally by the rear cab mounts thanks to a leaking rear window, its also missing a lot of support by the passenger side a pillar. So i have been looking for a new cab and couldnt find anything for under $2000 but reg cabs seem to be a dime a dozen and have found an entire truck for 600 dollars. before i make the 6 hour drive to go get it I want to make sure i can swap bodies. such as the body mounts lining up and wheel base being different?

Edit: sorry for spelling body wrong in the title like an idiot

 

From what I've seen the frames are different for regular and extended cabs, mostly in the length of the frame under the cab before it kicks up for the box. Basically what this would mean is that if you were to remove your extended cab and short box, put the regular cab on, put on the long box the front of the box at the cab would have no support whatsoever. Also, the wheelbase would be slightly off between the two configurations.

That being said, the frames for these trucks are apparently somewhat modular. Rather than being one piece per side there are three sections riveted together: front to firewall, firewall to back of cab, back of cab to rear.

You could theoretically remove your cab and bed, blow out all the rivets between the sections and assemble the frame back together as needed; regular cab and whatever box length is better.

What all is wrong with this other truck? In the end it might just be easiest to swap over drivetrain components...

 

I'm guessing on this, so hopefully someone with better info can chime in (that's my disclaimer. Haha..)

But if you have the Extended Cab with a 6.5' Bed, I would think that you could swap it for a Reg Cab, but the frame is long enough that you'd need an 8' bed. I would think it may be simpler to buy the 600$ truck and swap your motor into it.

Food for thought anyway.

Keep us posted, I'm curious what you end up doing.

Edit: Posted at the same time as chrmar did. So do what they said! Hah..

 

the 600 dollar truck is just your run of the mill 2wd work truck with a hole in the block lots of miles but a rust free body which is what im ooking for. where as my truck is a 4x4 so swapping over the body would be easier. my truck is also a 7700 series and id like to keep that option as I kind of take advantage of it and use the truck regularly i also did the v10 swap in my truck along with a 5spd swap. this was all done before i realized how horrible the body was of coarse, cause thats just the way life goes. im wondering if any one has some measurements on wheel bases between the two? as long as the wheel wells fit over the tires accordingly i can just make the rest work. Chrmar i do know what you are saying about the bend in the frame but i somewhat remember my old reg cabs bed going over that bump like you had described?? do not quote me as im not sure

 

With a regular cab frame, the kick up starts just behind the cab. If you put the regular cab on the extended cab frame, you'll have a gap of around 24" behind the cab before the frame kicks up. You would have to fab up some mounts for the front of the box and you'd have a huge hole there.

I believe the wheelbase is pretty close on a regular cab, 8' box and an extended cab, 6.5' box. Maybe only a difference of a couple inches?

 

after looking at some old pictures the frames look almost exactly the same. except for placement of the body mounts. the kick up on my truck starts about 1/3 of the way back under the rear ext cab door. right about where the reg cab would end. the reg cabs have different body mounts for the front of the bed which i could cut off the 2wd truck frame and weld onto my 4x4 frame with out much hassle. the onlthing im not sure about is how big of a PIA moving the actual rear cab mount on the frame will be. If I do end up doing the swap it will have to be done in ONE weekend as its my daily driver. i plan on pulling the "new body" and getting it all ready to go about a week before i pull the body of my ext cab to save some down time. I need to fin a reg cab long bed that i can measure for wheelbase and body mounts to see what im up against. im pretty positive the kick up in the frame is in the same location

 

7700 had thicker frames

 

Just how bad is the rust at the rear cab mounts? If I was in your shoes, unless it's totally gone, I'd much rather fix the rusted area than to get into a whole body swap. Pics would be nice.

 

pretty far gone it would be a lot of work to get rid of all the rust. its been a plow truck in north east ohio for the past 3 years and has spent its entire life here so that hasnt helped the truck any

im not quite sure that i understand the point your trying to make? the frames are only made of a thicker steel, while retaining the same design

 

I think his point was that if you were to start swapping frame sections as I suggested, you'd need to find a RCLB 7700 truck.