Community Forums

rmtravis · 04-02-2023, 06:41 PM

I have a '22 Keystone Passport 189RB with dual axles. I replaced the original tires last year with Goodyear Endurance ST205/75R14D tires.
The GVWR is 6,430 lbs. which works out to a max load of 1,607 lbs./tire
Keystone specifies 65psi (with the original tires)
Goodyear's inflation chart shows a max load of 1,640 lbs. @ 45psi and 2,040 lbs. @ 65 psi.

Is there any real advantage/disadvantage (mileage, softer ride, durability, etc.) to keep them at the max psi. or should I reduce it some?

Would it make a difference to split the difference to 55psi (1,850 lbs)?

Last year we went to Alaska from Michigan with no problems (at 65psi) and will be going to Utah and do more boondocking (probably more dirt roads) later this month

Dutch Star Don · 04-02-2023, 07:25 PM

Typically, the Keystone rating is the MAX tire pressure. They don't want people who will never weigh their trailer to run it overloaded at a lower tire pressure.

As long as the Goodyear tires you installed are the same ply and rating or higher than what you removed, I would run them at the pressure recommended by the Goodyear tire chart. Overinflated tires will wear the center outs and beat the heck out of the trailer unnecessarily. With that said, I would split the difference at 55 psi since you intend to take it off road.

TXiceman · 04-02-2023, 07:48 PM

The GVWR is not carried by the two axles. Typically, about 12% of the GVWR is on the hitch or 772 lb. This leaves about 5658 lb. on the two axles. However, this may not be carried equally between the two axles.

The ONLY way to know for sure is to get actual weights (with trailer loaded for travel) on each wheel. Then using the GY tire load chart, air the tires to the level for the highest loaded tire plus 5 psig, but not exceeding the maximum per the tire sidewall.

Ken

Gary RVRoamer · 04-03-2023, 09:59 AM

To meet federal safety specs, the trailer axles must be rated to carry at least 90% of the trailer GVWR. The other 10% is tongue weight. That actually works out to about 1450 lbs/tire if the the weight is equally distributed. Equal distribution is rather "iffy" though, so I'd assume more like 1600/tire until I could get a scaled weight. That says the 45 psi and 1640 max load is fine for your trailer. I would not go much beyond that.

Excessive inflation makes the ride rougher, increases the skid potential, and can lead to the center of the tread wearing more than the outer edges. Probably not much to worry about at 50 or even 55 psi, but I would not go to 65 without some really good reason (and I cannot think of any such!).