Tire PSI for hauling firewood

South VA said:

Well, just for fun, I searched a bit and found this:

1992 Chevrolet K2500 Tire Pressure

1992 Chevrolet K2500 tire inflation pressures with the recommended tire pressure, trims, original equipment tire size sets, winter tire pressure, tire load index, tire speed rating and other information.

tirepressure.org

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Yeah,I ain't buying it! Front to rear bias is almost always heavy to the front on PU's. The longer the bed(wheelbase)the more front bias. EC's move the weight back a little more. CC's with really short beds are closer to having a 50/50 bias than most other PU's and vans,Blazers and Suburbans are probably the closest to 50/50.

PlayingWithTBI said:

Sorry but, no they don't, load range E is also a suggestion (CYA), someone is going to use something different and need to adjust accordingly

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Ok. Looking back on my response to your post, I have to say that I don’t care for my tone. It comes off as a bit confrontational, and that’s not where I want to be. My sincere apologies.

You're right, of course; many of us do mount different wheel/tire combos on our trucks, and will adjust accordingly.

My understanding has been that the load range and pressures printed on the Certification sticker are based at least in part upon engineering. If someone is running the stock size tires (like me, for example) those would be the pressures to use.

However, I don't have any real proof of that. Out of curiosity, I've been trying to find a source to explain how those metrics are derived, and haven't had much luck so far. Which is interesting.

That said, I didn't even bother to check if Komet's tires are the stock size or not. As you suggest, it makes a difference.

South VA said:

Ok. Looking back on my response to your post, I have to say that I don’t care for my tone. It comes off as a bit confrontational, and that’s not where I want to be. My sincere apologies.

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No biggie, I didn't take it as a bad attitude. You were simply stating a point of information, I was thinking out of the box. We're cool

My tires are the stock size for a z71, which didn't come on this rig but I did loot all the pieces from a real z71 truck.

You guys have been debating so much I had to go check the official recommendation in my door jamb:


Oh yeah, that vent is missing a self tapper. Gonna have to leave the door shut at SEMA this year.

Eons ago I snapped a pic of a 7200# GVW truck's door sticker in the junkyard but I'll be damned if I can find it. I do seem to think I recall the RAWR at 4600# and the truck came with 245/75/16 load range D. I think.

Why dont people just run them a little bit below 100% like I do...

I do lots of towing etc in my 3/4 ton and I’m at 45 psi no matter how heavy the load is. I use the chalk test to inflate to get an even wear pattern and over the years this has been successful. Running max pressure on the tires doesn’t help the comfort level and normally leads to un-even wear from my experience.

My goofy buddy loves to overload his vehicles (and trailers.)

Examples

This trailer tire is NOT under-inflated. It's heavily-loaded.


He went out-of-his-way to get "1-ton" rear leaf springs installed on his '89 K1500. And thirty- or forty-ply tires, too. Then he expects to inflate the tires to the moon, without ever considering the weight rating of the wheels they're mounted-on, or the weight rating of the 8.5" axle they're bolted-to.

Put enough air pressure in the tire, and hit a big enough bump...and blow the bead-holding side of the wheel into outer space.





OTOH, I was the third person in the cab of an early-'70s half-ton Mopar pickup with a leaning tower of power and 3-speed; traveling ten-ish miles from the mine to his girlfriend's home with a box full of coal. I remember it as 4000 pounds, but it was decades ago, that can't be right. Tires inflated to the max, and still squished flat on the bottom. Springs so flat that the truck rode on the bump-stops. That poor truck was a Dirty Old Dog Goin' East, and it had my total respect.

Before I got a real truck I used to overload my black 05 1/2 ton and it wasn’t very smart. I worked that poor truck way too hard and yes it got the job done but wow what a difference now that I have a truck designed for my abuse.

I didn’t take a photo but I went to get a load of sand once and the guy asked? Are you taking half of the load now and half later? It can handle it, dump it in the box. It had to have been 2600 pounds and it was dangerously bottomed out in the rear . I was lucky I didn’t cause an accident.

Now with a truck designed for this stuff it’s a lot more safe and comfortable! Big power, big brakes big axles, so much better.

Scooterwrench said:

You're only going to be hauling this load for a short time and I'm guessing in cool temperatures. 2500lbs is a pretty good load so air the rears up to max and add ten to the fronts. Airing up the rears will help to reduce rolling resistance and you will be adding a little more load to the fronts. Once you get the truck unloaded let the air out to what you were running before.

Pickup trucks are almost always light in the rear so normal rule of thumb is to run the rears with less air than the fronts. Only way to know how much air to run is by tire wear. If they wear the middle more than the outer edges then you have too much air in the tire,if outer edges wear first then not enough. A tread depth gauge is a handy tool to have for determining what air pressure you need to run. Measure outside and center of your tread depth when the tires are new,write it down then measure in 500 mile increments and adjust air accordingly.

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Uh.. no you would never run less air in the rear than the front. It a truck , the given is it's usually weights less in the back unless it has a permanent fixed load ( service body, etc.). GM finally realized normal every day families aren't loading trucks full. That's why there's a two different psi ratings . A lower everyday psi rating for rear tires and a higher psi for when you get that 2 yards of gravel, or 12 bale's of alfalfa run at higher pressure.
Tires are constructed for specific maximum weight ratings. With that higher pressure is required to maintain proper profile, and footprint contact.
Like I said before, running the 86 suburban with 50 psi on all four, was so harsh your fillings were coming loose. Next pee stop I dropped all to 35 . Back on the road, my uncle the driver said " see they just had to warm up and ride better " . Yeah, that's why I do the maintenance not you.