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I have 7.50 x 17 Bias tires on my 1 ton pickup. What pressure do the rest of you use?

What is the ply rating or load rating of your specific tire?

I use 10 ply / load range E
I put them at 90 psi for heavy loads as indicated on the tire.
But if I’m driving around almost empty I drop them to about 40-50 psi for a bit nicer ride, not that it makes a big difference
-s

I have Tornel 8-ply rated load range D. Tires are marked 75 PSI. I’ve been using 40 PSI. I won’t be hauling any heavy loads. It rides as smooth as you would expect for wooden wheels. I’ve been thinking that is at least partially due to flat spots and wonder if adding more pressure might help with that problem, but I don’t want to get carried away with too much pressure.

You have wooden wheels?

I'm with -s -- In my 49, I run what the tires say. Inflation isn't just about the tires. It's also about keeping those multi-piece wheels together. I'd hate to have something come apart (from hitting a pothole or something) at speed because of underinflation. But he's right -- If you are looking for a comfy ride ... you have the wrong vehicle.

I called tech support at my tire manufacturer, Cooper. I gave him unloaded and max loaded front and rear axle weights and he told me appropriate pressures for both conditions. I have one piece wheels.

I use THIS for my daily driver truck. But it only has modern tire sizes, so doesn't help those with 7.50 x 17 tires like the OP. The load/inflation pressure table is dependent only on tier size and load rating, not manufacturer. I haven't found a table like that from any other manufacturer on the web however.

If I'm missing something here, please feel free to enlighten me ...

But ...

Are we making this too hard? What's the issue with just using what's written on the tire itself as a guide? So far, it works pretty well for me.

There are safety issues, as well as wear issues, with both under inflation and over inflation ... so why monkey with it? Just inflate to the manufacurer's specs and be done with it. If the ride is too harsh ... put some weight in the back

Just remember one thing. It’s a 1-ton truck! Tires are only a small part of that so called ride that they offer. It’s the springs that make the ride harsh! Mine runs smooth as wifeys Cadillac when it has 2yards of dirt in the bed. I am planning on adding 3/4” steel plates to the frame for that extra weight in the future. That should calm the bounce down.
Drive on!
Jim

Well I’m overthinking it apparently. I’m not expecting a smooth ride, just looking to do the best with what I’ve got. I’ve had little experience with bias tires and the three piece rims are kind of scary. Sounds like John‘s opinion at least is that more inflation would be less dangerous.

Mike -- Do not fear bias plys on 3-piece wheels. That's what I run on my 1-ton and I routinely run at highway speeds (`65 MPH) without issue. When I got my new tires mounted, though, I got them balanced. Above 65, which my truck is capable of, things begin to get a little ... uncomfortable. They are, after all, bias ply tires and do have their drawbacks. But 60-65 suits me well enough, so life is good. I am thinking that in a few years when it comes time to replace them, I may go with tubed radials.

But proper inflation is important for safety -- keeping those pieces together when spinning around fast enough to go highway speeds. The other important things are having good tires on good wheels. Keep those wheel parts clean and rust free. Properly inflated, good condition bias plies on well-maintained 3-piece wheels will give good, safe service at highway speeds.

Now ... How are your brakes? Your steering? Those need to be maintained, adjusted and and in spec, too.

Lastly ... got seat belts? Fire extinguisher?

Hey John, I’ve kept my truck stock so the top speed is about 45 at best. Brakes are excellent but I do need to adjust the steering box, buy an extinguisher, and consider seat belts.

Thanks to all for your inputs.

I'll bet John does the same kind of pre-trip inspection on Charlie that he does on his working truck- - - -the Peterbilt! Us "professional" drivers, even retired ones like me, tend to do that every time we get behind a steering wheel, no matter what the vehicle happens to be! That's a good thing, BTW!
Jerry

Speaking of ...

Today's ... adventure. Got to the shop to switch trailers for the 50-ton RGN to move our big excavator, I found two flats on the trailer (two out of twelve ain't bad, right??). I also found no fluid showing on the power steering reservoir dip stick (hmmm, truck drove finme yesterday ... maybe I should wear my glasses when I check that ...). But everything else was good. I even tested the air horn and rotating beacon before leaving the yard. One of our other Petes is currently out of service because it failed the pre-trip brake test... I think that issue is in the dump body gate lock system ...

Anyway, got all hooked up, air up and I was on my way.

What happened after that is ... a story for Wrenchfest ...

Anyway, the moral of the story is to stay on top of those tire pressures!

John

Air Force alert pad preflight inspection- - - - -"Kick the tire and light the fire!" The reason B-58s were only stationed at two bases right in the middle of the North American continent- - - -Little Rock AFB, and Bunker Hill AFB in central Indiana was the longest flight time for an ICBM from Russia. We had 14 minutes to get the birds launched for a last ditch retaliation strike in case anybody pushed the doomsday button!
Jerry