tire pressure on BFG AT (1 Viewer)

sailor

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So I did a search or two (honest) Found some threads about other tires/sizes but was wondering if anyone has some thoughts on the pressures I should be running in my At K/O 295 75 16. This is on a daily driven HDJ81. Tire store says 50 psi but this seems high compared to what I read here about other tires. 50 seems way too high and the dust on the tread indicates I will wear the center pretty fast. Any help? Thanks!

(Is there/ should we have a tire pressure thing in the FAQ with things like brand,pressure,size,lift etc?)
 
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Load range C I would say around 32 to 35 psi. An old sage once told me to inflate and then run through some water and then on to dry pavement and see that there is total tread contact. That would be your correct psi. JMHO
 

1973Guppie

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it should say on the tire what the max air pressure is, there are different tires and different load ratings, so impossible to tell you what you "should" run on your tire, look at the sidewall.......
 

sailor

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Load range C I would say around 32 to 35 psi. An old sage once told me to inflate and then run through some water and then on to dry pavement and see that there is total tread contact. That would be your correct psi. JMHO
That's what I thought, but was influenced by the guys at the tire shop. Now at 37psi front and 35 back with a huge improvement in ride quality and noise. I suspect the HDT is a bit heavier than the gasser so I upped the fronts a bit.
 
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Lka1988

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Sidewall pressure is MAX pressure, not recommended pressure.

Owner's manual usually tells you what pressure is best for your truck with different loads (provided that it's still stock).
 
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I have written about this ad naseaum.

You do not adjust your tire pressure based upon whether you run a load range C, D, or E tire, all use the same pressure to carry the same load. The only difference is the heavier load range tires have a higher maximum pressure which allows a higher load capacity when inflated to the higher pressure. The load curves are the same below that pressure, so a Load range C, D, or E in the same size all have the same load capacity at 35psi.

What you do need to do is adjust for the fact that you went from a P metric tire to a Light Truck (LT) tire. There is a method for doing this using the load curves for each tire, but basically how it works out is that you need to add 8-10 psi over the stock pressure, which means you should run 40-42 psi.
 
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Load range C I would say around 32 to 35 psi. An old sage once told me to inflate and then run through some water and then on to dry pavement and see that there is total tread contact. That would be your correct psi. JMHO
32-35 is way to low for an LT tire, I made that mistake with my first set of BFG A/T's and ended up with premature wear on the edges of the tires. See my post concerning how to adjust pressure when going from a P-metric to LT tire.
 
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I'm running BFG MT KM's (305/70/16) and have been using the chalk method since day one and came up with an average of 43-45 psi

Couple weeks ago I decided to contact BFG to see what they recommend :meh:

I gave them the tire size, make, model, the GVWR of the vehicle and they came up with 42psi cold for best handling and treadwear :cool:

I was surprised to see how close the chalk came to their numbers, but now it has me wondering what kinda pressure calculator they use :hmm:
 

sailor

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Well I can't read Japanese so the owners manual thing is out. Also these are not the stock tires. Also the previous skins it had on it were bias Swampers. Also I searched the site and obviously missed the threads that would have helped. With 44 pounds, only the center of the tread was on the pavement as witnessed by the drive through the water test. I wil try the chalk line (thanks) but posted for help to get me in the ball park for a starting point. There is a label on the door pillar that states the 31 10.5 15 LT stock tires reccommend 2.2 kg/cm2 (31.8 psi) so perhaps you gusy can see why I was hesitant. Thanks for the helpful advice!
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Box Rocket

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I run 35 psi mostly, sometimes 30 psi on my 315/75 size BFG AT's. I have over 40K miles on them with very even wear and still have about 1/3 the tread left. I'll take that any day from a tire. I've been very satisfied with that kind of treadlife and wear and that air pressure seems to have worked just fine even though it's much lower than what many are saying here.

There are many trail miles on these tires too, run between 15-18 psi mostly but a few trails as low as 12 psi. This pic is from New Years Day at 12 psi. As you can see, there is still good tread left after well over 40K miles, enough to still work darn well in the snow.

 

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