The Stovebolt Site Forums The Shop Area General Truck Talk tire pressure

I'm running radial tires (p235/70) on my 67 1/2 ton. There isn't any info on the truck or owners manual what air pressure to run. Been running 32ft, 36r. any thoughts? Also I've got a 3 speed should 1st gear be syncronised? Sticker in glovebox list option #4m01aa HD clutch. Thanks for help.

Mark

The tires air pressure should be on the tire.Every tire is made for a application and should have the wt. range and the air pressure once you change a tire from "stock" you need to go by the tire that you installed.

On My 52 3 speed 1st gear is not syncronised ,but I don't know at what year they changed that ,sorry.

Pete

tire pressure depends on how much weight you're carrying - could be the same all around, should be a range recommendation on the tire .... the syncro first didn't come out until '68, nothing to do with the clutch - the later trans would bolt right in if you find one

Bull

I was taught that the air pressure listed on the tire is max pressure allowed for that tire. For handling and safty you are to follow the vehical manufacturers recomendations for air pressure not what is on the tire.

I don't use the truck for hauling, I've got another truck for that. We use it as a spare vehical and plesure driving.

Here is a Goodyear chart of recommended pressure for various styles and sizes of tires and load weights. Light truck tires are included.

So if you put radial tires on a 50s truck you should go by the owners manual ,no you go by the tire specs.on the tire thats what the tire was made to operate in,that wt. and air pressure.When you buy tires for say a 2005 1/2 ton chevy truck the place you're getting you're tires from should sell you tires that are made for you're truck that will match the owners manual spec. on the tires.If you change things as putting radials on a 50s truck like I did you need to operate the tire as per the tires specs.on the tire.


Pete

I think in theory vehicle tire pressure specs makes the assumption that the tires used will exceed those specs. For example your vehicle might say 32 psi, but the tires that came on the new vehicle might say 45 psi. If you run 45 psi it's gonna be loose and dangerous.

On my 1951 1 Ton, I have Yokohama radials and I run them at 45 lbs. If I get down below 35 lbs I get wear patterns on the front tires.

You should go by vehicle manufacturers specifications for the load range tire installed. The max pressure listed on the sidewall is not the recommended running pressure, only the max pressure the tire is rated for. Changing to an aftermarket tire does not affect the recommnended tire pressures, unless a heavier tires is installed thant oem (like going from a P rated tires to a C range LT tires). Now, having said that, you may need to run the pressures a bit higher if there is a handling or wear issue, using the factory spec as a guideline.

What Longbox55 said is what I've always been told since the 70s (my brother worked for Goodyear in late 70s early 80s).
Tire pressure listed on the tire is max pressure that the tire can safely be used at. The pressure you should run is what is given by vehical manufacture not tire sidewall max presure. I have a pamplet from goodyear I picked up a couple of years ago that also confirms this. I didn't meen to open a can of worms I just was wanting to know what Chevy said the psi should be. Granted it may not list radials but I can use it as a starting point.