Tires: tire pressure, replacement tires, 1998 chevy 1500

Question
1998 chevy 1500 w/ 122000 miles... replaced the orgional tires at 80000 miles. The orgional tire pressure plate on the door for the tires stated a pressure of 45 psi... the new tires I have ( which are a different brand )state on the sidewall a pressure of 35 psi. what is the proper pressure? I am currently running them at 45 psi and they seem extreamly " hard " when I hit a bump, go over RR tracks, etc.  thanks MIKE

Answer
Mike,

If you'll look closely, I think you'll find your placard says the tire size is LT245/75R16.  And I'll bet the replacement tires are P245/75R16.  The difference being the letters P and LT - and those are completely different types of tires.  

First I recommend you get the place you bought the tires from to replace them with LT tires like the placard says.

But it might be OK (but not recommended) to use 35 psi in the P245/75R16's.  At that pressure, the load carrying capacity is the same as the LT at 45 psi.

Hope this helps.