Question about Cab 12 Chevrolet FAT

[Niels V]

I will see if I can find a parts book then.
I have bought a 41 Cab 12 Chevy fat in reasonable condition, but it is missing all "internal" parts in the front brakes: Liners, springs cylinders etc.
and I have 44 Cab 13 C60m that is getting broken for spares so I was wandering if I could use the front internal brake parts from the C60 for the FAT, or if had to replace the whole axle (front and rear)
It will be awhile before the FAT is delivered because of paper work and it is in another country, and therefor I can not check if the parts are the same.

[Hanno Spoelstra]

Originally Posted by Niels V

I have bought a 41 Cab 12 Chevy fat in reasonable condition, but it is missing all "internal" parts in the front brakes: Liners, springs cylinders etc.
and I have 44 Cab 13 C60m that is getting broken for spares so I was wandering if I could use the front internal brake parts from the C60 for the FAT, or if had to replace the whole axle (front and rear)

Niels,

I am not sure, but would hazard a guess that the brake parts are the same as the CGT used the same mechanical components as the C60 3-tonners. Would be best to save the C60L's complete axles if you have the space, otherwise save the brake back plates, internal brake components plus drums. That should give you enough options for the CGT while you go through the parts lists and sort out the details. I'll check my manuals to see if I have the info.

Hanno

[Niels V]

All the mechanical part and the original body parts will be kept from the C60M but most of the body work is postwar danish and rotten so thats going in the bin

[Bob Carriere]

Some early Chevrolet Gun Tractors....Also knows as CGT had the specail heavy duty casted from axle which differed from the typical CMP later production front axle. ..... and from my experience and photos ...that special Heavy Duty cast axle had similar eggcups mountings and brake plate of a 16 inch CMP front axle.....
.....................even when 20 inch rims were installed.

Early cab 11 CGT had that front axle one is at the Kars Museum.... I also found such a large axle on a 1942 C15a ....... but it is the 4 bolt eggcup which would not exchange for the larger C60 axle......

Now to complicate things early FAT also known as Ford Artilery Tractors also had GM front axles.......

So my advice is save all you can from the C60 if they do not fit they can always be traded for other parts later...... once you have you gun tractor home start taking pictures of your front axle so we can identify it for you on the forum.

Photos 1,2,3 are from the Kars cab 11 CGT photo 4 is the same CGT with rare early cast GM rear axle
Photo 5 is Petrolia's famous Ford FAT with GM axle.

[Phil Waterman]

Hi Niels

According to the MB-C1 Manual C-30, C-60 and C-GT all share the same axle gear ratio 7.16 to 1 so a unit swap should be OK from ration point of view.

What is interesting is the track FRONT and REAR

C-30 Front 70" and Rear70 1/2" Tire Size 10:50x16
C-60 and C-GT Front70 1/2" and Rear 69" Tire Size 10:50x20

But as has been said the best way is going to be to look up the parts numbers for the different units. If you are going to acquire reprints of the manuals, parts book you should also try and find a set of the service bulletins as there is a lot of useful information in those as well.

Service Bulletins -B-62 for example has detail information on spring rates and what is interchangeable with what. One of the things that comes out in that is that the 1941 FAT and all 3 tons had 10 leaves and 1950 Load rating while the 1942 which would be Pat 13 it jumps 15 and 2900. (I'm not sure of the number of leaves at 15 may be incorrect.)

CMPs a lovely jig saw puzzle.

Cheers Phil

[Niels V]

Hi guys
Thank you very much for your answers.
I will have to see what it has when I get it home, Sadly I didnt get proper pictures of the front axle on it, only these.
It had, by the way, some very nice rear tires on.

[Bob Carriere]

From the pictures you have just posted your front axle is the lighter model intended for 16 inch rims such as CMP C15a......although the larger 20 in. tires will fit quite well and the gear cluster may have been changed to the 7.16 ratio as it will bolt in.

From my experience the brake drum and all brake components of your gun tractor will not interchange with the brake parts of a C60 front axle.

Bob C