Must be the larger size D's take less air pressure, my 285/75R16's in a D call for 65 and every E rated tire I ever looked at call for 80 psi, I've never had Toyo's though, or 20'' tires

 

I would only go by what the door says if you are running [B]exactly[B] what came on the vehicle from the factory. It makes absolutely no sense to me what so ever to go by the recomendations for one tire when you are running something completely different. I go by what the sidewall says. I had a set of D rated tires on my truck that called for 65 max, and just put on a set of E's that list the same max of 65. As far as I can tell, the only thing that the letter stands for is the number of plies the tire has. I have seen D's that have a higher actual rating in pounds than some E's. There, my rant

 

Actually the PSI on the sidewall is the max possible psi for that tire and you're supposed to go with the inflation pressure recomended by the vehicle manufacturer. Of course that means for the same load range tire specified on the door tag.

 

I figured that post would spark a little controversy I guess I should have said that I usually run my tires around 50psi, unless I'm doing alot of towing then I will bump them up to the max. But if I had a tire with a max of 50, I'd probably go with around 40-45.

 

I wonder how you guys get a tire shop to install D rated tires on your truck, I've asked several tires shops and they all tell me the same thing they are not allowed to sell and install a D tire on any vehicle that came from the factory with E rated tires.