The GMC CCKW

Many find their CCKW not quite what they expect after they get it up and running. It is too slow," are there any high speed gears I can install?" Not really', your CCKW was a compromise that resulted in a truck with on the road and off the road capability.,
Sorry, but what you see is what you get.

*LOL* Never heard such a statement before. What do these people expect from a military vehicle? A race car?

I get that impression at times, and there is no solution, just talk.

I have even heard "esteemed experts" who write articles in national publications tell people you can go 50-55 with a stock CCKW.

You can for a little while....

Of course, all the people who say or believe this never seem to have a CCKW at an event. If you want to go a little faster, there are ways.

Just remember, at above the designed speed, you are exceeding the design of the truck, steering, brakes, and handling are being compromised. It is 1930s- early 40s technology.

I think 40-45 mph is fast..... I guess I have too many green toys.

I got Betty Boop up to 55 MPH one time and could hardly hold her on the road. Of course she was being pulled by my wife in my pick up, because the fuel pump had quit , and once my wife starts talking to someone in the car with her, she does not pay any attention to her speed. I kept blowing the horn and waving for her to slow down , all to no avail. After the harrowing ride, I jumped all over her for going so fast. Her remark," then get someone else to pull you next time, I quit." and she did.The next time I had trouble I had to call a buddy for help.

It may be a funny story now AD, But I bet it wasn't so funny at the time


Cheers
John

Actually the CCKW and Chevy were very advanced for the WW2 era compared say to the Dodge.

Recirculating ball steering was carried thru till rack an pinion in the 70-80's and replaced all the other types of steering systems.

Huck brakes (rears on a CCKW) were used by GM till 54) and on trucks with higher speed

The Lockheed brakes on the front of the splits were used till the 60's some time

The front end design was used up until recently virtually unchanged

The U-joints are the same as one used on trucks today

The later 270 and 302 engines with the flat top pistons (as opposed to the WW2 "turbo-top" pistons) were produced thru 1962 on trucks made for trucks for highways speeds. (watch out for your head bolt tightening sequence on newer engines, they are different!)

My experience with the 302 and 1,000's of miles and the Chevy's with non-dipper engines and higher speeds, again with 1,000's of miles convince me that you can gain a little more speed from a CCKW with appropiate modifications. And trust me, my HMVs do not get the all that TLC that Joel's get

If anyone want specifics, contace me via PM

And in the end, trucks maintained like mine will be the ones wanted by most that know CCKWs

Does anyone remember the character played by comedian Red Skeleton who remarked "Whoa, aw c'mon horsey, whoa!"? It ended up with the sound of a crash.

It 100% relates to the odds and mods that happens to these old CCKWs.

The M-37, produced til 1968, and on the original PW in production til 1970, used the WWII brakes.
Saginaw Ball and Roller Steering from 1939, and used up thru recent years does not mean advanced or modern, it was a satisfactory design that workedWe now have Saginaw Power Sreering with smaller steering wheels. U-joints are SAE standard and there is no need to obsolete the industry standard sizes. The 1972 GM pickup is my all time favorite, but GM had to keep up with the Joneses and we now have $40,000 pickups that make us feel good.
Good parts and maintenance are what keeps a truck in service, and CCKW is product of years of spares that are rapidly disappearing.

As for High speed Driving, the friction from the spur gears in the transfers at higher than designed speeds builds up excessive hear, leading to premature wear.
The transfer with all those spur gears is a giant eggbeater, and will self destruct when abused.

The best way to get HI speed from any HMV these days is to trailer it then you can get those 65 and 75 mile per hour modern interstate hi-way speeds

There are no spur gears involved in high range.

All the gears are helical gears

It is still an eggbeater with a minimun of 6 gears engaged to in High Range in the Banjo. Lot of friction and heat in direct proportion to speed. More Speed= More wear, noise and heat. You can't avoid it.

Some will say, use GO 140 in order to tolerate the heat.
Ordnance did a study in WWII and recommended against it. The heavier viscosity created more friction and heat.

Many owners have CCKWs that have steering knuckles that may not be in factory spec when it comes to the Steering Knuckle Bearings, these are a major factor in steering effort. If the knuckles bearings are worn, it is possible that the weight of the truck is being carried by the front axle shafts. When this happens the bushings in the spindles will instantly wear out, and in the case of Banjo Axles, the outer axle seal will fail.
No amount of mods will substitute for proper PM if the steering knuckle components are worn out or misadjusted.
Not many owners have the skil to disasemble and set up the steering knuckles.
65 years takes a toll on the front axles,and it may not be safe to assume that they have been maintained to specification.
There are many parts that are not avaible for the front axles, one of the important parts that have disappeared are the pins for the Tie Rod Ends, there are none to be found.