Originally Posted by mjodotcom
I had heard secondhand that it is usually a good idea to run with a higher tire pressure (closer to tires rated pressure vs the Jeep's 36psi recommendation) when towing. Is that accurate?
Yes, depending on the tongue weight of the trailer. Keep in mind the 36psi is just the vehicle and a standard load of a couple of passengers and maybe a suitcase or two typically. But the 265/50-20 Fortera tires are rated for a max pressure of 51 psi, and at that inflation will handle 2100 lbs each, or roughly 4,200 lbs on the rear axle. Figure that at 36 psi it's something quite a bit less.
As an example, my Goodyear Marathon ST225/75-15 trailer tires will handle 1760 lbs each at 35 psi, but 2150 lbs at 50 psi and 2540 at 65 psi. So upping pressure from 35 to 50 increases the axle load capability by almost 800 lbs.
When towing my trailer (weight between 6000 and 6500 depending on what's in it) and tongue weight of 600-700, I inflate my rear tires to 42 psi cold, and when running at speed they'll bump up to 45-46 hot.