Recommended tire pressure for Nitto Ridge Grapplers P285/70R17

I currently have them at 38-39 psi all around (cold). Should I go little lower?

 

Do the chalk trick. Mark a line all the way across the tread in a few places and drive in a straight line. If the chalk wears off just in the middle of the tread, there is too much air pressure in the tire. If it wears off on the outsides but not in the middle, there’s too little pressure. I like mine to wear off across the middle and leave about a half inch or so on both edges of the tread. You can also use a sharpie pen if you don’t have chalk.

 

I have the same tire in a C load. 34 front/32 rear seems to be a decent spot for ride quality/mpg

 

3rd Gen Tacomas take whatever PSI is required to obtain a 2,149 lb load rating from P-metric and euro-metric tires.

You do not have a P-metric; you have a euro-metric with a standard load index of 116. It obtains a 2,178 lb load rating at 27 PSI.

 

I’m running 34 all around currently. I forget what article I read that said to keep your psi somewhere in between a 10% increase from your cold psi to warm psi. So 34 cold your driving psi should end up around 36/37. This of course will fluctuate during cold and hot days. If it increases too much then psi too low, doesn’t increase at all too high. 11.5k miles on my last set of tires before I sold them and they wore evenly.