Originally posted by Phil Rohtla:
This is bad advice (sorry!)
Good rule of thumb: go by what the tire manufacturer recommends not by what the sticker says on your door.
For one, the vast majority of tires are not made specifically for a given car. Therefore, there is a wide range of different weights and pressures put on a tire by each different kind of car. When Ford designs the suspension of a car, they determine the needed pressure of each tire in a complex ride/handling equation (the case of the Explorer was the exception, not the norm).
A tire manufacturer's max pressure is how much air the tire can hold without blowing out after running for a while and heating up. It is NOT in any way, shape or form, their recommended pressure. Call any tire manufacturer in the world, and they will tell you this is the case.This is interesting Phil. I have worked at tire plants and closely with the tire engineers so I posed this exact qeustion to them. I was told that the tire is designed to be run at the pressure printed on the sidewall! Heat is built up in the tire by underinflating it not overinflating it. They told me that if you are driving at speeds of 70 MPH or more you better be running your pressure at the MAX pressure printed on the side of the tire or it could overheat and BLOWOUT.
When I told them that running my tires at that pressure caused a rough ride they explained to me that I needed to bump my pressure by 1 pound check wear and continue to do this until I get a good wear pattern. Once I acheived this if I was going to be driving at 70 MPH or more to bump the pressure up by 2 lbs.[not to exceed the pressure on the sidewall] and leave it.
Oh by the way I run 38 lbs. all around my dealers service people can not believe how well my tires are wearing. They say they have never seen KDW's wear this good. Every time they change my oil they set my tire pressure to 32 lbs. and I put it right back to 38. I think they want to sell me more tires. NAhhh they wouldnt want to do that, What was I thinking?
:p
