QuestionI HAVE LT315/75R16 TIRES ON MY '02 FULL SIZE CHEVY CREWCAB (3/4 TON) TRUCK AND WOULD LIKE TO KNOW THE BEST PSI TO PUT IN MY TIRES FOR BEST WEAR AND MPG. THANK YOU.
AnswerRuben,
I am hoping that you have replaced the original rims as they were 6.5" wide and an LT315/75R16 requires a minimum of an 8" wide rim.
But let's check your vehicle placard to make sure I have correct information. If I remember correctly on GM trucks, the vehicle placard is located either on the driver's door or on the doorpost. It should say the original tire size was LT245/75R16 inflated to 65 psi front and 80 psi rear.
I also hope you have Load Range D because Load Range C doesn't have enough capacity.
If you have Load Range D tires, the equivalent load carrying capacity as the original tires occurs at 38 psi front and 48 psi rear.
The more pressure you put in a tire, the better the fuel economy. I should also mentioned that a bit more pressure helps stiffen the tire and improves the overall wear rate. This is inspite of not giving the most even wear. Put another way, stiffening the tire improves the wear more than would be indicated by the evenness across the tread face.
However, if you haven't changed rims, you have a problem with the rim width and this is going to cause the centers to wear more rapidly that the shoulders. This might also cause some stability problems - wandering, sensitivity to wind, etc.
You have a real dilemma and unfortunately the stock rims do not allow any up sizing as they are maxed out on the original tire size.
