Airing down with a 10 ply tire. What PSI?


I am running Cooper ST Maxx tires on my 06 Tundra with factory wheels and was wondering what you guys aired down to on your trucks with 10 plys? I don't want to lose a bead but I want to make it a little more tolerable. We've had almost 25" of rain on the ranches I hunt over the past 3 months and the roads are brutal



Search and Rescue first responder
how much does your truck weigh? what type of terain do you drive on? there are so many variables. I run 315-70-17 D's on a dodge diesel, for comfort I air down to just under 30psi on off tarmac driving. it doesn't take much for comfort.


Expedition Leader
20psi seems to be a good balance of comfort and flotation but still allow you to drive on country roads without issue.


Right on, thanks! I'll start at 30 and work my way down to 20 to see what works best

I'm in NM. We've had two rains over 5". Wrecks everything! Monsoon season was good to us though and I'll never complain about moisture in that country. Some areas of the ranch got 15-18" and one area had more than 25". I'm hunting 300,000 acres there


i would start at 25PSI and go from there. I ran the 265/75/16 MAXX's on my XJ (4100lbs loaded) at 20rear 25 front when on pavement and 15 front 15 rear when off pavement.


Expedition Leader
Center your tire on an 1" piece of square tubing and air down until both sides of the tire touch the ground. This method provides a good working metric with all tires and vehicle weight.


I am running KO2s (E rated) on a Nissan Frontier with a Four Wheel Camper. BFG recommended not going lower than 20 psi. I usually do 25psi offroad and 18 psi on sand (beach driving). Not problems at all.


Im probably not as heavy as you are but run load range C 265/75-16 Duratracs on my Tacoma as low as 12 lbs in the sand and offroad on mountain trails. I regularly take the load range C 35/12.5-15 BFG KM2s on my Jeep TJ down to 10 lbs when off-road. With all the armor and tools it probably weighs 5,000 lbs. A good friend regularly takes the 33" load range Cs on his TJ down to 8 psi. Neither of us run beadlock wheels neither has ever thrown a bead. I'd guess that load range E tires should be even more secure. But just in case I always have a 2" ratchet strap and a can of starting fluid or WD40 in the tool box in case I need to "explosively" reseat a bead. My compressor doesn't put out enough volume to do it otherwise.


Active member
I´m suprized no one has mentioned the chalk test (google it). When I chalked my new BFG at ko2 e 265/75/16 I found that 38 front and 35 rear (empty) was good. I had them all around 50 psi at first and it was like driving the flintstone mobile.

As for offroad I usually air down 30% to around 22 psi and less in deep soft sand or sharp rocks.