i have 31/10.5 bfg a/ts and was wonderin what psi you guys think i should be filling. As of now i have 32 psi and i do pretty much all on road driving so i dont need to know the best for off roading but i know that i should air down some if i do. The stock psi was 25. Any help would be appreciated.

 

What does it say on the tire? My revos say the max is 80psi and I'm running them at 60psi. I don't offroad very often so I usually don't air down when I'm out there.

 

Here's a good test to figure out just the right pressure.....

(stolen from lifted97ranger)

It went along the lines of driving through a puddle and seeing what type of tread you are leaving on the dry ground....then adjusting from there. The rear pressure should be lower than the front pressure. What you want, is a proper "footprint"......so your tires wear evenly.......if the outside is heavy and middle is light, add air. If the inside is heavy and outside is light, take a lil out.

The side of the tire will tell you max psi when the tire is cold. When I air down off road...I'm usually airing down to anywhere from 13-20psi. But I play in snow, rocks, and mud.

 

I'd say go with 32 and just look at the wear patterns for your particular style of driving. If you see the center getting thin in the next 1000 miles then drop it 3psi and go another 1000.

btw, once you get over 32-33 psi (on a typical pass car tire), the rolling resistance from sidewall flex and tread distortion is next to nothing.
Source = Fundamentals of Vehicle Dynamics by Thomas D. Gillespie


Rich

 

just remember that the max written on the tire does not factor in the weight of the vehicle...

 

look on your door and thats the max that ford factory puts in there tires.

 

ford puts it up to 25psi but me and my brother(a mechanic for Toyota) thought that to be a little low and there is no uneven wear except on the outside of my tires cause i used to drive like a maniac, and by maniac i was taking this one corner near my house at around 30 to 35 getting completely sideways and counter steering. i think i will just keep it at 32psi and see if i start to notice any uneven wear. thanks for the input.

 

i run about 30.. probably needs to be taken down though

12 on the trail

 

I agree here, I ran my Yokohama a/t's at the recommended 32psi for most of their life and they are just about smooth in the center and have plenty of tread at the edge. When you go to larger than stock tires, like I did, you need to realize that most are made for heavier trucks than rangers. The lighter weight doesn’t make the tread flatten out as it would on a full size truck at the same pressure. I have dropped mine to 25psi and had a more even tread wear, BUT you should keep an eye on yours (different tire brands/ rubber compounds wear at different rates) and see how they wear, it doesn’t take long (4-5k miles) for the center to wear allot if they aren’t right.

 

On my stock BFG A/Ts in 31x10.50R15 alcoas i ran 40 psi. BFGs dont wear right unless you run high psi. The dealer dropped the psi in my dads 07 and they are all chopped to hell right now. I have 30k on my stockers when I sold them and they where a little less than half worn.

 

i run 35 psi in my BFG tires

 

35 psi. The higher the psi the less bulge there is as the portion of the tread that is rotating into the road squashes against the pavement. That's what causes the majority of the resistance / friction / heat.

 

on my goodyear at/s i run them at 35 psi

 

31x10.5x15 BFG All-Terrains , I run mine around 34 psi. Any less and they bulge out at the bottom.

 

12...

 

I uhh.. air mine up to 92 PSI o.O

Nah, actually, im sitting at 34-36 roughly on mine.. tires tell me roughly 45 on cold, and I usually put all my tires at 34/35/36 ish anyway.

 

i run 28-31 with my bfg at's.

im running 28 right now because of the snow/ice.
it seems to grip a little better in the snow with the lower psi.

i think the lvl2's come from the factory with 30 or 31psi, its on the door sticker.

im running 8" wide rims, so who knows.



and to the guy running 60 psi and thinking the side wall pressure is what you should run... : :

 

aka he should run 12psi




seriously!

if nothing else it looks sweet

 

32 is about right for what your running