Engine: 1945 US6 Hercules JXD 320 CID Flathead Six Motor

[Buzzard]

It looks like we are stuck here in BC for yet another winter due to our government continuing to close the border with the USA.
I have pressed my 1945 US6 into service ( 10 Wheel Drive with chains on front tandems) as a massive snow plow one half mile up our mountain driveway.
My question for all you lubrication experts is this: After purchasing 20+ years ago, I performed an oil and filter change using 30W Non-Detergent oil as I felt that was probably what was originally used. When cold it does take longer than I like to build oil pressure. It is time for a full service before winter hits again.
What viscosity (it gets cold here) would you recommend and what type of oil would be most suitable? I have a good supply of Diesel 15w40 -Would this be appropriate?
Thanks for any expertise you can offer.
Cheers,
Bill It should be pretty obvious why I have traditionally spent our winters in Arizona.

[jclary]

Thanks for sharing your wonderful Studebaker-related machine with us. But, a so-called lubrication expert in one region might not be as "expert" as one who lives near you in the north where "real" winter is a given. You might make a friend with some local fleet maintenance mechanic in charge of vehicles that absolutely must perform in the frozen winters of the north. Most folks where I live would have a problem recognizing the plug-in for a block heater, let alone contemplating having to warm up oil or fuel to get an engine to turn over and start.

[Lark Hunter]

Depending on the what the expected ambient temps you're going to be running it in (I presume winter), I would pick either a 10W-30 or 5W-30 (latter if you're going to be starting below 0 degrees F and staying below about 60 deg F. 10W-40 or 15w-40 would acceptable down to 15 degrees or so. I've never used non-detergent oil in a combustion engine.

And yes. I grew up in Northwestern Montana, so am used to low temperatures.

[Buzzard]

Thanks for your insight John. I contacted my local lubricant wholesaler and he in turn contacted his supplier who endorsed 10W30 full detergent oil for my application.
Cheers, Bill

[studeski]

Don't use diesel oil unless it says for diesel and gas. Diesel only oil(type3?) will gum up from gasoline fumes.