PDA

View Full Version : Tires


staffa6
05-28-2019, 05:14 PM
I have a 2018 Keystone Passport 2810BH with trailer king tires ST205/75R14 D8 rating the max psi for these is 65psi. While driving I have a TPMS that shows the psi moving to 70/71 psi. Is this safe or should I reduce the amount of psi in the tire to allow for expansion while traveling? What is the max psi while traveling for this tire? Also the TMPS I have, has a place for temperature, what temperature should I set it at.

Thanks

Snoking
05-28-2019, 05:33 PM
I have a 2018 Keystone Passport 2810BH with trailer king tires ST205/75R14 D8 rating the max psi for these is 65psi. While driving I have a TPMS that shows the psi moving to 70/71 psi. Is this safe or should I reduce the amount of psi in the tire to allow for expansion while traveling? What is the max psi while traveling for this tire? Also the TMPS I have, has a place for temperature, what temperature should I set it at.

Thanks
NO! PSI ratings account for the fact that the pressure goes up as the tires warm. That is why is is called cold inflation pressure. Chris

JRTJH
05-28-2019, 05:34 PM
If you look at your tire sidewall, it will say something like: "MAX COLD INFLATION PRESSURE 65PSI"

Trust me when I say that every (EVERY) tire engineer at every (ALL OF THEM) tire manufacturer knows that "heat expands".... They all have "designed into the tire" the ability (and the expectation) that the tire pressure will rise when the tire is in use. That pressure increase is FULLY EXPECTED and is FULLY ENGINEERED into the tire.

You should NOT decrease any pressure, simply set the COLD inflation pressure per the recommendation on the trailer tire pressure decal (located on the roadside forward sidewall of the trailer. That recommended pressure will likely be the tire "maximum COLD inflation pressure" which is 65PSI. Then, fully expect that the inflation pressure will rise as the tire "heats up to operating temperature"....

Essentially, what you're looking for on the TPMS is a "dramatic difference" in one tire.... If you see that, it's time to inspect for reasons why it's different. If they all "go up together, go down together and stay about the same" then you've got nothing to worry about except staying between the white lines and under the speed limit !!!!!

GHen
05-28-2019, 10:08 PM
My tires are max 80 pounds, I also have a a tst507. They regularly get to 90 on a sunny day. I saw a chart showing that increase is normal, I think I set my high pressure alarm is set for 92.

Ken / Claudia
05-29-2019, 07:59 AM
As an example I have had my truck tires start in cool temps in PDX OR cold tire at 80 psi. Near end of day.
In Redding CA air temps were 115F truck tires were 94/96 rears tire psi. That was heavy towing. As said "Cold inflation" and all tires heat up with use and PSI increases. If you set the TPMS up to see tire temps, likely none will be exactly the same. That's normal also. Tires facing sun will be higher than ones not. Side to side might be within a few lbs psi.

travelin texans
05-29-2019, 10:02 AM
You can also drive yourself nuts if trying match the TPMS pressures with your pressure gauge, believe me, if they ever match exactly it's totally by accident.
Also on the TPMS all 4 tires will usually have different pressures & temps while traveling. What you're watching for is the one with the extreme difference in temp or pressure.