"LT" tire pressures on Expedition
I moved up from "Heavy Load" tires on my Expedition to real "LT" tires. Max air pressure on the new tires is 80#, max pressure on the heavy load tires was 50#. I always ran my other tires at max press...
Forum Discussion
Ralph Cramden wrote:
Be careful what you read on forums, especially RV ones. You're not going to blow out a valve stem by airing up to 60 lbs, or even 120 lbs, nor will your factory OEM wheel grenade. The pressure rating of your OEM wheel, if it even has one, will be more than the pressure any tire requires that will physically fit on it along with a substantial margin for safety/ error. Don't inflict yourself with a case of Rv board OCD.
Yup, be very careful what you read on internet forums - including the post above. If the installers used regular valve stems (Why wouldn't they?), the valves CAN be blown out by excessive pressure. In the case of regular passenger car valves - the kind your vehicle came from the factory with - the max pressure is 65 psi. It is likely the installers used the same kind.
And to answer your question, I have to ask a question: What was the size of the tire that came originally on your vehicle and what pressure was specified for it? And what size did you replace them with? Without those numbers, no one can tell you what pressure to use.
BTW, there should be a sticker on the driver's doorframe - commonly called the vehicle tire placard - that will list the original tire size and the pressure specified for that size. The replacement size can be found on the sidewall - and be sure to include the letters in front of an/ore behind the size. Those numbers tell what kind of tire and affect what pressure to use.
Assuming for the moment you replaced the original P metric tires with LT tires with the same dimensions, the LT tire requires 15 psi more than the P metric tire to carry the same load.
