Forum Discussion

PursuitInsight's avatar
Jun 15, 2017

Air pressure with the tire off

Hi,

I always check and fill the rear dually tires while they are off the rv.
I want 95 psi or 100 for extra safety and varying load.
Front are 110 and done easily.

i do not have valve extensions. even the back external tire is not accessible since the stem is short.

I only now realize that maybe the pressure will increase once the tires are back in, and pushed with the rv weight.

Am I right that the pressure will increase, how much should i put to get the proper result pressure
  • Effy's avatar
    Effy
    Explorer II
    PSI is not affected whether they are on or off the RV. Why do you take your wheels off?
  • Take your RV to a decent truck tire shop and tell them to change the valve stems to something that is accessible. These DO NOT have to be the flexible extensions since there are rigid valve stems and rigid extensions of almost any shape that can be used to make your task easier. There is no reason why you should have to remove the tire to add or check the air.
  • Run TST Tire Monitor System keep an eye on pressures, add as needed (seldom), but every 6 months I do a actual per tire check with a very good quality gauge. I have more low pressure readings on the toad than the motorhome.
  • If there is and pressure change between a loaded and unloaded tire it will be slight and not much of a factor. Considering you should check the pressure early in the day that travel is scheduled removing the tire to do so introduces additional risk that can be easily avoided with valve extensions. If an owner feels that flexible extensions are too high of a risk of failure there are hard valve stems that can be installed that allow easier access for pressure checks and adjustments. Also consider a tire pressure monitor which will eliminate the need to manually check pressures.
  • Thanks for the replies.

    I check the pressures once a year, before a longer trip. I will do it this evening. it allows me to check the disk and brakes pads at the same time.

    From year to year, I can say that it does not change much. i have to add air every 2 years

    I am thinking about extenders, maybe next year. I am getting older
  • As mentioned, temp affects the pressure, not the weight. And get a good extender, keep away from knock offs. When we installed the new wheels and ***Link Removed*** on the truck, we are surprised with the incorrect reading and was figured out due to the bad extender.
  • Do you take the tires off of the car to check the air pressure in them? You're overthinking and overworking this issue.

    Bill
  • That's a lot of work just to check tire pressure, get some valve extenders, pressure is the same on or off RV..
  • NOPE.......
    Tire pressure is same when adjusted on vehicle or off vehicle

    Pressure changes due to temps but not due to weight.
    (It's a volume thing)



    And you really need to get/install valve stem extenders so tires can be checked/adjusted while on vehicle.
    Tires should be checked/adjusted EVERY 'travel' day COLD. Pretty tough to properly do IF you have to remove tires to do it!