Bed swapping 50 to 55

[enick72]

Just wanted to be clear before buying something I can't use. Sre the 47-53s different from the 54-55 because it's 2 inches deeper and the rails are flat? The reason I'm asking is because I'm having a hard time finding complete bed for my 55 but I have found a whole 50 that I can buy for a good price. My plan would be to swap beds but just want to make sure that mounting is the same along with running board match up etc.

[Steve@OldSub.com]

I expect there would be some small differences in the mounting. I don't know that to be the case, but knowing how the beds differ I would not be surprised. What you can't do is put a '54-later bed on an earlier truck because of the difference in bed depth.

Well actually you can do it, I've seen it done. I don't think it worked.

[mr48chev]

I don't think you will have any problems as I don't think the first series 55 frame is any different than the earlier frames dimension wise. I have a 54 frame under my 48 and the 48 box bolted up fine.

[Steve@OldSub.com]

Originally Posted by mr48chev

I don't think the first series 55 frame is any different than the earlier frames dimension wise. I have a 54 frame under my 48 and the 48 box bolted up fine.

The kickup is higher on the earlier frames. I have no doubt putting an early box on a late frame would be easy, going the other way is not.

Putting a late bed on an early frame ends up looking like this.



This particular truck was a '54 or '55 1st GMC with Hydra-Matic with a damaged frame. The restorer chose to repair it by using a '53 frame not realizing what the result would be.

The asking price was too high for a truck done right so I quickly went the other way.

[enick72]

I do remember reading that in 54 the bed was lowered for ease of loading and unloading and straightened the rails to give the extra couple inches.

mr48chev
I don't think you will have any problems as I don't think the first series 55 frame is any different than the earlier frames dimension wise. I have a 54 frame under my 48 and the 48 box bolted up fine.

Was this a direct bolt up or did you have to use spacers in places or fab anything?

[ClassicDreamer]

I have a 52 bed on my 55 cab. The chassis is a s10 though. Bunch of mods as well. I filled that gap show with a piece of flat sheet metal.