Tires: Over sized tires on a 1990 Jeep Cherokee., jeep cherokee laredo, proper tire pressure

Question
I have a 1990 Jeep Cherokee Laredo.  The placard on the jeep says the original tires where 205 75R/15 and a tire pressure of 30 PSI.  The jeep currently has LT235/75R15 on it.  What is the proper tire pressure for these larger tires?

Answer
Dino,

I do not recommend using LT tires in place of P type tires - and the reason will be obvious in a moment.

In order to carry the same load a P205/75R15 does at 30 psi, an LT235/75R15 needs to use .... Ah..... Mmmmmm.... well, it turns out that it is off the lower end of the chart - and I don't like recommending anything off the chart.  The chart ends at 35 psi, and I consider that the lowest usable pressure, because it is possible to unseat a tire off the rim in extreme maneuvers at low pressures.  So I would recommend you use 35 psi even though it is way too high for the load.  I don't want to be the guy who makes a recommendation that could cause you potential danger.

I would further recommend you do something about the tire size.