K5 frame change

[Poze]

Will my 84 K5 body bolt up directly to a 78 K5 chassis?
I am thinking the body mount locations are the same 78 and up and that 78-80 still had closed frame ends So I would just need different bumpers and mounting brackets If we made the swap.
Thanks

 

[Chickntrk]

Didn’t the floor of the tub change in 78?
For sure 78-80 had closed frame ends because I had to cut mine to get my winch cradle to fit

 

[Poze]

Yes the rear floor changed in 78 to add passenger foot room And a folding rear seat.

 

[6872xtc]

I put a '90 body on a '79 frame. I used mounts for the '79, but I have no real idea if that is necessary, I had just read it more than once on here to match the mounts to the frame.
I did have to pull my radiator support forward a little when assembling. I believe that it was due to a wreck in the past of my '90. It always had too tight of a door to fender gap before. I loosened the bolts and things got close enough to bolt up with a little pressure pulling forward with a come-a-long.

 

[ZombieK5]

Will my 84 K5 body bolt up directly to a 78 K5 chassis?
I am thinking the body mount locations are the same 78 and up and that 78-80 still had closed frame ends So I would just need different bumpers and mounting brackets If we made the swap.
Thanks

Poze, Glad you posted this. doing nearly the same thing however I am putting a 78 body my choice 77 frame. The problem is the 78 body came with the extra space for the backseat passengers to have foot room. My 77 Frame and Body did not have that. There are differences between the 77 and 78 frames. I would love if you could send me photographs of your 78 frame. I am interested in the area of the frame where the body mount is located that is closest to the back seat. I'm talking about the body mount that is pretty much located correctly between the two wheels. I would love as many photographs as you could send. Feel free to message me privately. I'm trying to determine what I need to do to make the 78 body fit on my current frame.

 

[Big Ray]

Waaaaaasyyyyyyyyu back when Ian and Jessie were on Trucks.tv
They did the Urban Gorilla, a hummer body on a suburban frame.

First thing they did to the stripped frame was cut of the frame to fit the body to the frame.

they laid 2x4 sections on the frame, located the mounts and drilled through them.

 

[Poze]

Zombie K5. I will get some pics for you tomorrow. The 78 frame I have is 2wd but I don’t think that matters as far as body mounts.
also someone removed the mid mount right in front of the leaf spring and the next mount behind it. I’ll try to describe it in the pictures tomorrow. Also a good utube video of what your want to do. He has a couple of good videos.

 

[Poze]

This is like my 85 and I suspect 78s are close to the same but I would like to know for sure without guessing. Frame spec books would be very helpful for some of these questions.
1. is not there on a 77
2 . is just a flat crossmember with no body mount on a 78 and up.

 

[Poze]

It might just be 1 and 2 that were changed for 78

 

[Poze]

I put a '90 body on a '79 frame. I used mounts for the '79, but I have no real idea if that is necessary, I had just read it more than once on here to match the mounts to the frame.
I did have to pull my radiator support forward a little when assembling. I believe that it was due to a wreck in the past of my '90. It always had too tight of a door to fender gap before. I loosened the bolts and things got close enough to bolt up with a little pressure pulling forward with a come-a-long.

I think you answered my question. Were the bumpers and bumper mount brackets different between the 90 and 79? I think in 81 the frame horns changed.

 

[ZombieK5]

It might just be 1 and 2 that were changed for 78
View attachment 415069
View attachment 415070

Mine looks like the bottom image. I am thinking I'm going to have to Notch the floor of the 78 body. Looks like I'll have to notch the corners where the floorboard meets the bottom of the B-Pillar

 

[Poze]

Mine looks like the bottom image. I am thinking I'm going to have to Notch the floor of the 78 body. Looks like I'll have to notch the corners where the floorboard meets the bottom of the B-Pillar

Can you change the crossmember and add mounts on the outside of the frame?

 

[ZombieK5]

Im probably gonna have to do that. Looking at a tube crossmember. Can make the final decision until I see some good 78 Frame shots. I had Kurt at DIY4X make me the required outboard body mounts.... Just need to see some good images.

 

[6872xtc]

I think you answered my question. Were the bumpers and bumper mount brackets different between the 90 and 79? I think in 81 the frame horns changed.

Yes, you are correct about the frame ends being different, starting in '81.
It didn't bother me because of custom fabricated bumpers, however.

 

[Poze]

Poze, Glad you posted this. doing nearly the same thing however I am putting a 78 body my choice 77 frame. The problem is the 78 body came with the extra space for the backseat passengers to have foot room. My 77 Frame and Body did not have that. There are differences between the 77 and 78 frames. I would love if you could send me photographs of your 78 frame. I am interested in the area of the frame where the body mount is located that is closest to the back seat. I'm talking about the body mount that is pretty much located correctly between the two wheels. I would love as many photographs as you could send. Feel free to message me privately. I'm trying to determine what I need to do to make the 78 body fit on my current frame.

Pictures of 1978 frame. They probably aren’t much help because someone removed the rear body mounts and crossmember.

 

[Recon 78]

78 gm manual

 

[Poze]

Thanks Recon78
Any chance you could repost picture of specs. Download must have cut some of it off.
Thanks

 

[Recon 78]

Sure, I'll try to scan it so it comes thru better

 

[Recon 78]

should be better

 

[Poze]

should be better

View attachment 415188

Thanks Recon78