53 chevy 3/4T Chassis

[solidaxel]

Can someone tell me the what the difference is in the lenght of a 3/4T Vs. the 1/2T frame?

I measured the front and rear width and the front is the same but the rear is 43" wide so not much taper at the rear. I want to place a 1/2T (53) bed on the long wheel base frame what problems am I going to have with the cab, core support, and the rear box?

I know I will need longer running boards and short aprons for the short bed.
CAn someone tell me what I am missing!

[Steve@OldSub.com]

The overall length of a '53 1/2-ton is 191-1/4 inches with a wheelbase of 116.

3100 dimensions

The overall length of a '53 3/4-ton is 200-3/16 with a wheelbase of 124-1/4.

3600 dimensions

Are those the numbers you are looking for?

[solidaxel]

Thanks Steve, that helps alot.
It looks like everything will fit but the rear width of the frame, which brings up the spring mounts which are removed along with the rear end.
I will have to sleep on it some more

[nickp51chevy]

Originally Posted by Steve@OldSub.com

The overall length of a '53 1/2-ton is 191-1/4 inches with a wheelbase of 116.

3100 dimensions

The overall length of a '53 3/4-ton is 200-3/16 with a wheelbase of 124-1/4.

3600 dimensions

Are those the numbers you are looking for?

I was just going to say 9 1/4", but that works to.

[solidaxel]

The section we added to the body is 10" I think we can cheat 3/4" in the rear mount and add a crossmember to the rear of the chassis to match the 1/2T bed rear crossmember

[nickp51chevy]

Sounds like a good play to me

[Dan Bowles]

I've got a 3/4 ton naked frame if there is anything you need "looked at."

I could mock up a box on it but you are right about the springs on the 3/4 ton being on the outside of the frame. It can't be that hard to put 1/2 ton springs under it or just use some "modern" springs from an S10 or 1500 truck. Those old springs are for a torque tube anyway so it might be better for lateral control to go with updated springs.

[Dan Bowles]

Just curious, how are you mounting your cab in the rear? Are you staying with the shackles or are you putting mount pads in like the front? Or is your cab old enough that it didn't have shackles to start with?

[solidaxel]

Originally Posted by Dan Bowles

Just curious, how are you mounting your cab in the rear? Are you staying with the shackles or are you putting mount pads in like the front? Or is your cab old enough that it didn't have shackles to start with?

Thanks Dan,
Yes that is where we are at in the moch up stage.
I am trying to justify spending money on another frame (3/4) or using the
1/2T we have and add 10" to the middle under the cab.
The cab is a 53 so there are shackles on the rear.
Looking for all the challenges before we get any deeper in the build

[solidaxel]

Originally Posted by Dan Bowles

I've got a 3/4 ton naked frame if there is anything you need "looked at."

I could mock up a box on it but you are right about the springs on the 3/4 ton being on the outside of the frame. It can't be that hard to put 1/2 ton springs under it or just use some "modern" springs from an S10 or 1500 truck. Those old springs are for a torque tube anyway so it might be better for lateral control to go with updated springs.

I just went out and measured the width behind the cab and in front of the box and the 1/2T frame is 37 1/4". is the 3/4T the same at that location.
How does the 3/4T box mount at the rear to the frame?

[Steve@OldSub.com]

Originally Posted by solidaxel

How does the 3/4T box mount at the rear to the frame?

Same as a 1/2-ton. A couple of ears on the cross sill with bolts through them into the frame.

Funny thing is just Sunday I looked at two '54 Chevy pickups, a 1/2-ton and then a 3/4-ton both with all the bed wood removed. Part of the purpose was to show a buddy exactly what is the same and what is different.

[Dan Bowles]

I'm just wondering if you need to do any floor stiffening where the shackles are. Not sure how the weight distribution changes with your 10" addition. That's why I was thinking of a second set of "front" mounts for the rear or even what some of the S10 guys are using back there.

[solidaxel]

Originally Posted by Dan Bowles

I'm just wondering if you need to do any floor stiffening where the shackles are. Not sure how the weight distribution changes with your 10" addition. That's why I was thinking of a second set of "front" mounts for the rear or even what some of the S10 guys are using back there.

I had not entertained that thought "Yet" but thanks for thinking ahead,
We did talk about a strengthing rib under the splice on the floor but not about a additional body support. Thanks
What do the S-10 mounts look like?

[solidaxel]

Originally Posted by Steve@OldSub.com

Same as a 1/2-ton. A couple of ears on the cross sill with bolts through them into the frame.

Funny thing is just Sunday I looked at two '54 Chevy pickups, a 1/2-ton and then a 3/4-ton both with all the bed wood removed. Part of the purpose was to show a buddy exactly what is the same and what is different.

The frame only being 43" at the rear than the rear cross sill must be different also, correct?

[Steve@OldSub.com]

Originally Posted by solidaxel

The frame only being 43" at the rear than the rear cross sill must be different also, correct?

I hadn't thought about that, but yes the 1/2- and 3/4-ton cross sills would need to be different because of the difference in frame width.

I looked it up in the LMC Truck catalog online and they show two different parts for 1/2- and 3/4-ton.

[xJoey Dubsx]

glad u asked, I needed these dimensions too! Just not yet, but down the road.