I feel dumb asking this question, but here goes....

I've had a set of 33" Nitto Terra Grapplers (325-60R18) for almost three years now (love 'em by the way) and they've just started to make some addt'l road noise (around 50K miles on them).

It got me thinking that maybe my tire pressure was off.

I do 99.9999% highway/on-road driving. What psi should I be running these tires at ideally? And is the tire noise common toward the end of this tire's life?

Thanks...

 

According to the website, those are load range D tires that will handle 3000lbs at 65 psi. I would run them at around 45.

 

depends what rims you are running them on. thats a pretty wide tire for a factory rim so id tend to run them around 35 to keep them from wearing in the center.

 

35 is way too low for a load range D tire. Yes width has a little to do with the pressure, but very little. At 35 the tires would be rated to handle about half their max capacity, or about 1500lbs. Times 2 = 3000lb for the axle. An 04 up rear axle is normally rated at 4000lb. Might be okay for unloaded, but who wants to have to add air everytime you carry a couple hundred pound.
On vehicles with a TPMS system and load range D tires, the low pressure to set the warning off is 38.

 

In my 295/70/17 Nitto TG's I am running 50psi. The handling feels real mushy down around 40psi. I've been running this pressure for about a year now and I haven't noticed any uneven wear even though they are mounted on factory 7.5" rims.

 

Thanks for the replies.

I'm actually running these tires on Eagle 178s (18x9). I've had them at 40psi for the last year or so, but I think I'll bump that up to 45 or so and see if there's a difference.

 

I have mine at 45 all the way around, most of the time. If I know that I am going to be hauling anything heavy (over 1000lbs) or towing heavy, then I pump them up to the max.

I have mine mounted on 18X9's also.

 

42 PSI

 

43-45 Psi

 

40 psi

 

44 psi 305 50 20 wheels are 20x10

 

The Nitto Terra Grapplers are mud terrains, correct?

 

They have different, both AT and MT.