Forum Discussion

RonR2440's avatar
RonR2440
Explorer
Jun 17, 2018

Tire pressure

I drive a 32' Itasca Cambria. I keep the tire pressure at 80 psi and the air bladder bags at 35 psi. When we are driving the RV seems to feel every asphalt repair, expansion joints, road damage, etc. Makes for a really rough ride. What do people typically keep their tire pressure at. I realize for the best results you can weigh the vehicle and look at tire charts. I am thinking of reducing tire pressure to 75 psi. I am concerned about tire overheating if I reduce the pressure too much. Thanks ahead of time.

14 Replies

  • And don't assume your tire gauge is accurate. I had a quality tire gauge that read 9 psi too much, meaning I was putting in 9 psi too little. You can read about my tire gauge evaluation HERE.
  • Tire pressure s/b based on weight of the rig not what's on the side wall. Have the rig weighed and then use one of the charts published by Tire Mfg to set the correct pressure - my Class C rear tires are set closer to 65 than 80 and that's based on the weight on my rig.
  • What does the door sticker say? That's generally the pressure required for the maximum axle weights and a reasonable starting point, at least until you can get a chance to weigh your unit (packed for travel) for yourself and see what the actual axle weights are. The tire companies have charts of weight vs. pressure to follow once you know the weights. (These are standard for a given tire size and type, so it's not really essential to find the chart from the company that made your tires.)

    For the typical Ford chassis class C, the rear tires usually end up needing 80 psi but the fronts are somewhat lower, 60 psi or 70 psi or so. Reducing the pressure in the fronts if excessive would help the ride some. Realistically you are not ever going to get a Cadillac ride out of a class C motorhome, though; it's basically a box truck that happens to have an efficiency apartment in the box.
  • 5 pounds will not make much of a difference.
    You should get the vehicle weighed. What chassis? Are the air bags front or back?
    Are they factory or after-market?