55-59 rear cab differences

[bigblock73]

Hi all, need a little schooling on the differences between the 55-59 cabs. The area I am specifically trying to understand, is the area just below the rear window at the door striker location. I have a 58/59 (I believe) GMC big window cab, and as you can see, there is a curve at the inside cab corner adjacent to the door latch. I believe this does not exist on all cabs, as I have seen some where its a straight across body line without the "swoop". Can anyone break down what defines this difference? Any additional photos would be greatly appreciated. Thanks in advance!

[dwcsr]

All the 58 /9 cabs were a little different than the 55/7, GMC was different from Chevy. I see on yours that the rear floor to back panel brace is much wider and the swoop you asked about. I don't recall seeing either of those features in a chevy 58/9 cab

[tsmith8]

Here is a picture of '58 Chevy for comparison.

[ptc]

I can tell you that the 57 chevy trucks didnt have that nice block off cover for the corner.... wish they had to keep all the garbage out of there!!!!

[bigblock73]

Anybody have a 55-57 picture they could share?

Thanks for the input so far everyone, all great information!

[OrrieG]

I never realized that the GMC's had the corner metal, I added it on my Chevy.

[58CameoAZ]

Know your asking about the rear of the cabs, but fwiw, there is a small detail between
the cabs at the gas pedal location, the 55 and 56 had a different gas pedal then
the later 57 to 59 trucks and on the later years the pedal was mounted to the floor and the trans cover, there is one square nut that was factory spot welded on the lip of
the Cabs trans cover location and then one nut was on the trans cover itself.
again FWIW,
Allen

[dsraven]

here is a pic of my 58 cab. it shows the floor being covered to the corner of the cab I think, no hole there.

[dsraven]

here is a pic of my Canadian 57 gmc. no curve on the brace and the floor looks the same as the 58 chevy cab I have.

[dsraven]

I think they both had the same type of shape to the rear wall to floor brace as well, where the cab mount is.both badly rusted by the way, haha.

[58CameoAZ]

Looks to be a difference at the lower part of the interior cross section between Big back windows
and that of the Small window trucks

[_Ogre]

Originally Posted by 58CameoAZ

Looks to be a difference at the lower part of the interior cross section between Big back windows
and that of the Small window trucks

i think 58cameoaz has hit it, additional bracing for the bbw
i've owned both but never had them side to side for comparison
my 58 has the swoop, it was a pia to fit my subwoofer/amp enclosure around

[ptc]

Dont know if this shows you much but this is my 57 chevy. The plate that is all welded into the floor next to the roll bar plate was empty before. Open access into the cab corner below. Which over 50 years filled with garbage about 4 inches deep.

[58CameoAZ]

PTC, Funny, I have the Same Exact metal filler plate configuration piece's made for both my 58&59,
and when you hold them up they look like ET. Lol...
Allen

[58CameoAZ]

I will say also, with putting in those ET Filler piece's i did not
put an inner Cab corner back in like stock as i think they are the total cause of the
Corners rusting out in the first place as all the dirt and crap (and Moisture) collect
down in that pocket and eventually rust it out.
Allen

[58CameoAZ]

Originally Posted by ptc

Dont know if this shows you much but this is my 57 chevy. The plate that is all welded into the floor next to the roll bar plate was empty before. Open access into the cab corner below. Which over 50 years filled with garbage about 4 inches deep.

Big Block73, I am not trying to high jack your thread, Seriously, but also want to add
that PTC i see in your Second picture that you welded the bracket that the
cab bolts go threw (welded to the back of the cab sheet metal)
I never could understand why that bracket was made that way and not attached to the cab and just to the floor?
Allen

[dsraven]

my rear cab to floor brackets were both attached to the rear wall and the floor. some fun getting them off too, I might add.

[ptc]

Mine were only spot welded... but with 1000hp going in this old girl, I want to make sure all the parts are gonna hold together. It's really just a 57 body on a pro mod frame but I want the cab to hold together so I'm welding everything up tight.