Airing Down

[JCTex]

I have Nitto Trail Grapplers 37 x 12.50 x 17. Nitto's site says they will carry the most weight rated for this tire (3,525) at 50 psi. My 2014 vehicle is expected to weigh ~6,500 and has lockers, sb disconnect, 4" long arm lift, stronger axles, and really good Fox shocks.

I'd appreciate some recommended air-down numbers for this vehicle for medium rock crawling, NFS rocky roads, dunes, and ~4" or less of snow.

Any comments about running them in town and highways at 50 psi would be appreciated. This particularly needed because the vehicle will be towed a lot behind a MH.

J Lewis
McK TX

 

[gmwelder86]

On the trail for rocks and such probably good with 10-15 psi without bead locks. With bl could go lower. Highway 50 seems awful high.

 

[HRPINDC]

I usually air down my KM2s to about 20-22 lbs for forest roads, maybe 18 if they're particulary rocky. 50 lbs sounds like a lot for street driving, but see how it feels and let some out if the ride is too rough.

 

[v_man]

I have same dimension tires , but KM2's . I air down to 15psi at least anytime off road, and 10-12 on more serious trails , have not lost a bead yet . I run 35psi on the highway , agreed : 50 psi seems really high ...

 

[JIMBO]

:sombrero: WOW, 6500 lbs--is that a 4dr /w modified camper setup ??

Shouldn't START at more than 4400lbs and 6500lbs already exceeds the max allowable--

What am I missing ?

Thanx

:costumed-smiley-007:wings: JIMBO

 

[codesertrat]

I have same dimension tires , but KM2's . I air down to 15psi at least anytime off road, and 10-12 on more serious trails , have not lost a bead yet . I run 35psi on the highway , agreed : 50 psi seems really high ...

This is exactly the way I roll. Never more that 15psi when off pavement, and usually 10 to 12.

 

[mikejr]

I run mine fairly low to begin with - 20-24psi on the street - but my vehicle weighs closer to 4k - I get even wear this way.

It should be fairly simple to play with airing down and getting to a point where you get decent flex without risking a bead: 10-15 sounds about right.

 

[aristobrat]

The best way is the chalking method to find the correct tire pressure.

Agreed.

OP, if you're unfamiliar with the chalk test, check out the last part of this article:
http://nitrogentiremachine.com/proper_tire_inflation.htm