M37 with Chevy 350 questions

[Landstew]

Hi all. I have been looking at buying my first m37. Have been reading /looking at these the past year and one came up. I was told it has a Chevy 350 that starts, but after further questions was told the clutch isn't hooked up. They somehow moved it under power to a better spot where it's been sitting.

Is this a bad sign of an incomplete conversion, or relatively straightforward to hook up? Are there other things I should ask that are important to this conversion?

Also body is just fine for what I want, but bed has holes. Are those easy to get and install for a good welder? Thank you!

[sturmtyger380]

Hi, 'Is this a bad sign of an incomplete conversion.' It's hard to tell based on your description. Do you have any photos?

Most conversions are custom type work and each one might have to be worked on differently.

Are the truck beds easy to find? Most are not in very good shape unless they are on a well kept truck. Holes are fixable but it just depends on how much good metal there is in the bed.

Alan

[John Mc]

I know nothing about 350 conversions

How is the frame?

You may want to look at upgrading the brakes, especially if you operate in hilly areas. When you start moving that 6000# truck faster with the 350 engine, you'll want to be sure you can stop it. Properly adjusted and in good condition, the stock brakes work surprisingly well, but higher speeds, hills, or pulling/carrying a load can call for better stopping power.

[Argie1978]

….after further questions was told the clutch isn't hooked up.

Sorry, I don’t get it…., English in not my native language. Do you mean the clutch is loose, like disconnected…?

Also body is just fine for what I want, but bed has holes. Are those easy to get and install for a good welder? Thank you!

The floor is like 1mm thick but with good work can be saved (depends on the hole ). In my case I had to procure a repro. Although some body parts can be found, as explained the price depends on condition.

[Landstew]

The frame seems very good. Very solid. All I got from them is that the clutch is not hooked up. I just wasn't sure if this is a common conversion or not and something you can get a lot of information on to help troubleshoot and finish.

[PoW]

In my 53 years of driving/rebuilding/repowering M37's I've come to find out the stock ring & pinions can't handle much more torque/speed than the stock motor can deliver. Such as you find in a small block Chevy engine.
.
The gears don't break, rather it just wears off the Formate coating on the teeth and they turn into razor blades in short order.

At the time synthetic lube didn't exist, and every gear oil additive available didn't make any difference.

I went thru 13 sets in my Detroit Diesel powered one in just under 250K miles.

And yes, the pbacklash was to spec, and several original NOS drop-ins did the same thing.

Unfortunately, those gearsets aren't as easy or cheap to source nowadays.

PoW

[Landstew]

Are there any ring and pinion upgrades for increased power?

[John Mc]

I went thru 13 sets in my Detroit Diesel powered one in just under 250K miles.

And yes, the backlash was to spec, and several original NOS drop-ins did the same thing.

Wow! Replacing a gear set on average just a little over ever 19,000 miles, and doing it 13 times? If I could not find something obviously wrong, I think I would have given up after 2 or 3 and replaced the whole axle assemblies with something else.

[PoW]

Are there any ring and pinion upgrades for increased power?

Yes, apparently the new production 4.89:1 gearsets are not made of the same material.

And when I get around to building another Diesel M37, it will have a Dana 70 or 80 axle, narrowed and rehubbed to take stock 5-bolt Budd wheels. The front axle never had any problems, as it usually was still with hubs disengaged.

Much less work overall than the old route I took.

PoW