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Posted By: rem141r question for the 4x4 sand guys - 06/15/15
i have a 2015 f250 with the stock bf goodrich rugged trails LT 265/70 17 tires. it has 3.73 gears and the 6.2 gasser. it has manual hubs and manual transfer case and electronic locking rear diff. the little bit of offroad i have done with it so far has left me kind of depressed about its performance. need 4x4 in wet grass to get up my yard. anyway, i took it to the beach the other day and was going to go in the sand and went to lower the pressure to the recommended 18 psi that the park service recommended. when i checked the pressure, it was way past 60, probably 80 but my gauge didn't go that high. i thought my gauge was broke but when i compared it with my van, it registered 40 which is what those tires should be. i let out a bunch of air and got it down to 45. i'm thinking that could be why the truck has sucked in wet and snow. the mfg web site said max psi was 80 and i think that was what the factory had in them. seems waaaay too high to me for even on road use, let along off road.

what do you guys run in yours? i'm thinking about 45 should be right for every day use. i will head to the sand again tomorrow and run it down to about 18 but i think those things will look flat. i plan on letting it out at the gas station across the street just to see what it looks like with 18. i would hate to get that fugger stuck and have to get pulled out with a friggen toyota or something. smile
What does the sticker on the door say? That's where they should be for on-road. For sand you want a really wide footprint, so the lower the better....of course too low and you'll unseat them from the wheel. 18 psi shouldn't be a problem...take them down that far and see how they look.
I had Long Trails on my Frontier,and while the mileage was good, performance on anything except hot dry pavement was utterly worthless.
When they wore out, I put some Wranglers on it, and it goes like it was 4WD. It isn't 4WD, though.

Got no faith in BFGs since then.
I'll bet your getting quite a bit more wear on the center of your tires at those pressures. Max pressure in a tire is for fully loaded, not every day driving. Hard to say what pressure you should be using as it varies with style of tire, width of wheel, weight of the truck, etc. The easiest thing to do would be to go off the recommended pressure the truck came with. A better way would be to chalk test it to see what works best for your truck. My guess is it's somewhere between 34-38 psi unloaded.
My opinion, but most 3/4-1 ton trucks suck off road vs 1/2 tons and smaller trucks unless they've got a load in them.
well the door sticker says 75 psi. thats probably what they had in them. that sounds incredibly high to me. i hate these tires and will replace them at some point in the next year. i just hate to do it before they are worn out but their performance is dismal so i'll bite the bullet one of these days.
Running CJ5's and Ford Broncos in the sand, I always let tubeless tires down to 10 PSI.

It give you a good footprint and is enough to not break the bead.

Virgil B.
good to know virgil. thats my main concern, keeping the bead. i think i'll try 18 and see how it does.
went with 18 today and it did fine. the sand was really soft and other than some wallowing when switching paths, it did great.
18# or thereabouts in a lightly loaded half ton Chevy has always worked for me but like you experienced, it gets a little wiggy crossing high ridges into deep troughs in sugar sand. I have driven big Fords but they weren't mine so I never looked at the door label.

I seem to remember Hunter S. Thompson pumping the tires on his rental car up to 75 or more in "Fear and Loathing in Las Vegas" but that may have been for other reasons than you or I may have never even considered......
Originally Posted by rem141r
well the door sticker says 75 psi. thats probably what they had in them. that sounds incredibly high to me. i hate these tires and will replace them at some point in the next year. i just hate to do it before they are worn out but their performance is dismal so i'll bite the bullet one of these days.


The 75psi is for GVWR or GAWR which for your truck is probably around 11,000lbs or 7000lbs for the rear axle. It should have a higher GAWR and higher psi for the rear as that is where most of the weight is loaded, but empty the rear is lighter and can use less psi. Unless you regularly carry weight or tow, there is no reason to run that high of pressure. Most trucks empty need less pressure in the rear tires than the front.

Here is a chart that should give some idea of weight rating for your tires at certain pressures: http://www.goodyeartrucktires.com/pdf/resources/publications/2010_loadinflation.pdf
I didn't see your exact tire size, but the chart on page 44 gives you an idea of how pressure affects weight rating. The tires listed at 35lbs were good for a vehicle weight of around 6000lbs and the same tires inflated to 80psi were good for over 10,000lbs. No need to run a tire that high unless you need to.


A lower than max pressure will give a better ride and usually better wear and stopping for everyday use.

Originally Posted by Lockhart
18# or thereabouts in a lightly loaded half ton Chevy has always worked for me but like you experienced, it gets a little wiggy crossing high ridges into deep troughs in sugar sand. I have driven big Fords but they weren't mine so I never looked at the door label.

I seem to remember Hunter S. Thompson pumping the tires on his rental car up to 75 or more in "Fear and Loathing in Las Vegas" but that may have been for other reasons than you or I may have never even considered......


ha. "as your attorney, i advise you to pump your tires to 75 psi and take this mescalin."
Wet grass will make most trucks look sick. You really can't get traction on it unless you get to the mud under it. It is eve worse if it is real tall as it then bends over and you are on a snot slick carpet. Can be really embarrassing to be stuck in the grassblush
Letting air out of one's tires is a well known trick that has been used for many years, particularly in soft sand.
Back in the 80's, I drove an old 1966 3/4 ton, 2WD Dodge many a time under such conditions. Reducing the air pressures in the old 7.50X16 tires mounted on split rim wheels would do wonders when I needed to drive up the sand wash behind Sand Springs or when I needed to cross the sand flat behind the Eureka Dunes of Inyo County. As long as I didn't make any sharp turns, I got around quite well.
What it does is make the tire footprint longer, which can give you 50-100% more contact area with the sand.
In my case, I'd go from 60 lbs. down to 25-27 lbs. When it came time to drive out of the area, I just kept my speed down and made no fast curves. Never had a problem.
My current truck is a 2006 Ram, 4WD. During the off season, when the truck is unloaded, I usually run the front tires between 55-60 lbs. and the rear tires from 50-55 lbs. I've gone through lots of tires doing this w/o any unusual tire wear. E

I don't consider myself an expert on driving in sand, but just got back from Florida in an area where vehicles are allowed to drive on the beaches. Many places are hard packed and anything will work. Other areas are loose sand and clearly marked "FOUR WHEEL DRIVE ONLY BEYOND THIS POINT". Apparently there are a lot of people who can't read, I saw several stuck only feet from the pavement. Most made it 30' or so. I pulled one Ford Expedition back to pavement with my Tacoma

The biggest surprise was the F-350 dually. The rear wheels literally sank deep in the sand less than 2' off the pavement. It was a 4X4 vehicle, but the gal driving it needed assistance to figure out how to get it into 4X4. Once there she backed out and discontinued her trip onto the sand. I'd have thought the duals on the rear would have helped some, but apparently not in deep sand.
or in snow......
i knocked mine down to 18 and it did good. the worst parts are right by the beach ramps. its like quick sand there. saw a ford escape buried to the floor boards and a 1500 yanking the schit out of it. driving in sand is definitely a different feeling but it was fun. we drove all the beaches down here from one end to the other and had a heck of a good time. kids rode on the tail gate and would jump off to grab good shells. i was pleasantly surprised that the more remote sections had really good shells. the downside is i will now be moving a bushel or more of shells around in the garage for years to come.
I regularly run sand trails in the Osceola and Ocala NF, and at the beach. My 4Runner has P235/75/R15 tires, inflated to 32 PSI. Only on rare occassions, do I come off that for sand.
If I do deflate, I drop to 22 PSI, and then use a 12 volt pump to bring it back up when leaving the woods or beach.
Roads like this go for miles, with deep, soft 'sugar' sand.
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