265/60R17 LT's and I keep them at 40. They seem happy there, I ran them up to 45 once and didn't care for the ride in downtown Baltimore, 40 gives me just a little bit more compliance to make the high frequency low amplitude sharp bumps not as jarring.
If you want the absolute best you need to use the chalk test, you will likely end up with the fronts at a higher psi than the rears if you go for the perfect psi.
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