PW Cab Mount Demensions/Measurements

[W_A_Watson_II]

The above sketch isn't to scale. Dist X is front to back, while Dist Y & W are side to side.

Well, I'm considering diving into the job of building the replacement cab for my '49 (the White One) Power Wagon. As this truck will be more of a restoration job than the a "Brake Job" like I did on the '46, I want to make sure I have some proper details. I've got a good floor and part of a good cab, these along with the good part of the existing cab will be put together to build a clean and nice cab.

I know the cab mounts changed (in mount elevation). 46-50 and 51 on had different elevation measurements between the front and rear mounts. But I believe (I'm confident) the fore aft (Dist X) and side to side (Dist Y & W) were the same.

Does anyone have the proper/correct measurements as noted in the above sketch for both the pre and post 51 model trucks?

Thanks,
Will

[W_A_Watson_II]

OK, found by Dodge Power Wagon Body Builders Layout Drawing and have everything except the elevation measurement. Any one have them?

X = 34-17/32"
Y*2 = 44-7/32"
W*2 = 48-3/32"

The frame holes are 1-1/32" diameter.

Will

[Desoto61]

I'll try and take some measuerments of my 46 frame this weekend, cab hasn't gone back on yet.

[W_A_Watson_II]

OK, Thanks!

[Desoto61]

Looking at mine I can't get a good measurement right now, it's sitting on uneven ground. The two mounts are each basically level with the top of the frame (maybe 1/8" lower), the front one at the back as the frame starts upward over the front axle just forward of the mounting spot. I'm hoping to roll it into the garage this weekend, I can do a better job with it then.

[W_A_Watson_II]

Desoto61,

Thanks, when I re-did my 46, I didn't have to do a major cab repair and estimated they were 1.5" difference between the front and rear. As the front uses blocks and the rear uses only a pad I was close enough for just moving the cab around. In the case of re-building the '49's cab I'll need to be as close to correct as possible as I weld the cab floor to the rest of the body parts.

The Wood Block is 1-9/16" and I believe the rubber isolator (Body Shim) was used on all four corners looking back at a detail pix. If that's the case and you are correct that the frame mounts are the same, then the early floor mounts are 1-9/16" different in elevation.

I wonder if the later cab's were all even in elevation?

[W_A_Watson_II]

Found some more of my misplaced info. From a 1/30/2010 File I had:

48 b-1 cab mounts

-> The forward drivers side is bolted hard to the frame sitting on the same 1-9/16" wooden block. There is no spring on this bolt as only the other 3 connections are allowed to flex.
-> The forward passenger side has the same 1-9/16" wood block and a longer bolt that contains the spring and castlenut on it.
-> The rear passenger mount has a 3/8" isolator pad only, with the same long bolt with spring and castlenut.
-> The rear driver mount has a 3/8" isolator pad only, with the same long bolt with spring and castlenut.

The wood blocks were used until 1951 then replaced by rubber isolator mounts. The wooden blocks could be replaced with 1-9/16" polyurethane isolator mounts if desired ( http://www.energysuspensionparts.com...s.asp?cat=3433 )

Here is the order of assembly from top to bottom: Bolt (head up - threads down), Washer, Cab floor, wood block (both front corners only, fiber pad, mounting brackets on frame, flat washer, spring (all corners except the driver's front), flat washer, castleated nut, cotter pin. The driver's side front corner of the cab uses a shorter bolt and no spring. This is the one out of the four mounting points that is held tight to the frame and is not allowed to flex. This is because of the steering box and column being mounted to both the frame and dash at this corner.

(Actually, that particular part of my writeup contains some errors. Corrected, it should read as follows: The earlier trucks mount each front corner of the cab to the frame mounted cab hold down bracket using, as spacers between the cab and bracket, one 1-9/16" wooden block and one 3/8" fiber pad per corner. The rear cab corners simply rest on the frame mounted cab hold down brackets using, as a spacer, a single 3/8" thick fiber pad per corner. All corners, except for the driver's side front, use a spring loaded mounting bolt to allow for flex between the cab and frame. The driver's side front corner uses no spring in order to provide for a rigid mount at that point. This rigid corner mounting is designed to prevent binding and flexing of the steering column, brake, and clutch pedals as the truck traverses uneven terrain.")

Here are my Reference Pictures as well I found:

[Desoto61]

Desoto61,

The Wood Block is 1-9/16" and I believe the rubber isolator (Body Shim) was used on all four corners looking back at a detail pix. If that's the case and you are correct that the frame mounts are the same, then the early floor mounts are 1-9/16" different in elevation.

I wonder if the later cab's were all even in elevation?

That would sound about right. The little trough behind the seat frame is that difference you are referring too, otherwise the floor is just about level back to that point.

I didn't think the cabs were any different early to later, which would mean the mounts changed position or design to account for the different mounts.

[W_A_Watson_II]

I didn't think the cabs were any difference early to later, which would mean the mounts changed position or design to account for the different mounts.

Ah, good point, and that makes since. The later on frame mount point on the rear changed heights to allow for an isolator the same thickness as the front (3/8" + 1-9/16"). Good catch.

This now means I can make a proper jig to build from THANKS!

[Desoto61]

Ah, good point, and that makes since. The later on frame mount point on the rear changed heights to allow for an isolator the same thickness as the front (3/8" + 1-9/16"). Good catch.

This now means I can make a proper jig to build from THANKS!

Great! Moving the mount makes the most sense from a production standpoint too, a lot more work to re-design the cab floor vice just moving or modifying the rear mounts.

Good luck!

[Jerry Henry]

Thanks for the posted info. Are there any specifics for the radiator mounting to the frame? As in shims, pads, or otherwise?
The reason I ask is because with my '46 cab mounted exactly as these specs show, and the hood fitting perfectly to the radiator shroud and the cab cowl, my bed needs to be shimmed about 2 1/2" higher at the rear of the frame than it is directly behind the cab. I hope the pictures show what I mean.

[W_A_Watson_II]

Jerry,

There are shims (added/deleted as required) to align the radiator height. Can's say how many were "normal".

As for your bed construction, that's strange. My bed mounts parallel to the non-hump portion of the frame. You can see more pictures and information on my Bed Construction HERE.

It sounds, and almost looks like your rear frame rails are bent down. If you study the PW Body Builders Layout Drawing, you will see the frame before and after the wheel hump should be flat.

[Jerry Henry]

Hi Will
I really don't think the frame is bent down. I remember checking it with a straight edge, but can verify it easily enough.
I noticed the space between your tire and the fender is greater than it is on my truck. And I have 900 16 StA tires which are really only about 34 1/2" in diameter.
I am wondering if the radiator shroud needs to be shimmed up and the cab shimmed slightly at the front. This might transfer back enough that the rear of the bed could come down.

[W_A_Watson_II]

My '46 has some super duper extra heavy springs on it, and even with the 1100x16's there is indeed a nice clearance in the wheel opening. Your front looks to be setting low to me, I wonder how tired your springs are?

If you are trying to level the bed with the ground rather than the trucks frame rails, then that would be your problem. The bed floor should be parallel to the frame, and if the truck has a rake (as yours might with weak front springs) then the bed will slope down hill in the front. Mine slops down hill in the front as well.

In your picture is the rear of the bed shimmed the 2.5"? If so I'd say you very likely have a bent frame.

The following two drawings might help you locate your frame/body issue:

[Jerry Henry]

I tried to make the side rails of the bed parallel with the raised detail on the cab, just below the side windows. This is also a parallel line with the running boards. I used a string line pulled tight between two anchor posts at front and rear of the truck to establish the parallel.
I can see where spring arc would raise the front of the truck and give more clearance between the fender and the tire, and it's likely my springs could use some help. :)
I will have to do some more checking to verify that my frame rails are straight. The charts you gave are helpful, and I will print them for reference. I recently had cataract surgery on my right eye and the same procedure is scheduled for my left eye in Dec., so I am not really able to do a lot with the truck right now....Dr.'s orders not to bend over, lift anything or get dirt/dust in my eye. It' s a hassel, but it's worth it to regain my vision.