So I just bought a set of 35 12.5 18 Nitto Terra Grappler G2 for my 05 F350. So far I absolutely love the tire, great traction, low road noise, and look awesome. My biggest thing is I don't haul much usually and I don't want them to wear faster than they should considering what I paid for them. I'm at 48-50 psi right now and there seems to be a little bit of tread still not touching the pavement? I was just curious as to what everyone else was running to get the best wear out of them.


2005 F-350 5.4L 6 Speed Manual. Leveled 2.5" on 35 12.5 18.

 

Just inflate them until you are happy with the contact patch. You don't want to over or under inflate your tires. On my truck F250 stock tires i run 65 front and 80 rear. but I may drop that down to 65 in the rear.

 

I run 325/65r 18's (35x13) on my 07 with a v10 and found that 40 in the front and 35 in the back works for me. Empty of course. As mentioned by The Bone, you can see the contact patch and confirm what will work for you. Ride is a lot better as well.

 

I used to take kids sidewalk chalk and rub a big line all the way across the tire. Drive forward a dozen or so feet until it starts wearing off. Decrease pressure until it wears off evenly across the tire.

That said, this is for off-road type tires, not highway treads and never with a load. I never went under the safe minimum pressure of (load / capacity ) * ( max pressure). I had ProComp Xtreme A/Ts in 35x12.50R17 and Nitto Trail Grappler 25/70R18s, the ProComps were fine since they were D-Rated I ran them much closer to max pressure for the load capacity (of just my truck empty), but the Nittos had a load index of 129 (4080#), I never ran them under 40psi (out of 80) because they got squirmy below that, even if the load pressure was fine. I was worried about premature wear with them still crowning a little, but they made it 42K miles before I replaced the set due to a sidewall puncture. They still had 6/32nds but they were 4 years old and starting to crack.

 

I just dropped mine to around 42 all the way around and they seem to be touching all the way aroind. Thank you for all your help guys

 

Chalk them run the truck on a flat level surface adjust tire pressure until the contact area is all the way across.

 

Toyo told me with my 35x12.5-18 was no less than 55 rear 60 front. 60 and 60 loaded.

 

I am running 325/65/18 and I always run 55 all around. It seems to work and run fairly even.

 

I think your 42psi is fine. I roll around with 40-45.

 

I chalked mine before I got the load inflation table from Toyo and weighed my truck. You would be surprised how close the chalk method got me to the correct psi for the load. It was within 1 or 2 psi.

The math that texastech_diesel shows is the same equation that I use also.

 

Old school works just fine now and then lol