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Gil_J
12-04-2019, 03:44 PM
Tire pressures seem to be a topic of much discussion and debate. The bottom line is that the only accurate way to set the MINIMUM pressure is to have your fully loaded coach weighed at each wheel position. Once that is done then consult the Michelin RV Tire Pressure Chart.

Lacking wheel position weights, get your coach weighed on a set of CAT scales that are at every major truck stop. Add some additional weight to account for side-to-side imbalance.

Lacking any weight measurements, refer to the data-plate installed by Prevost that states the tire pressures for the tires delivered with the coach at its maximum rated axle weights.

Here is actual weights and recommendations I provided to an owner of an 05 XL-II Double Slide.

* Steer Axle: I recommend an increase in the minimum recommended pressure to factor in for side to side weight differences. For long distance running or hot desert conditions, I personally would run 115 psi.

** Drive Axle: I recommend that you do not run a tire at Michelin’s lowest recommended pressure even though it can carry the weight. My recommendation is the same as Prevost’s.

*** Tag Axle: Due to the super single construction it’s best to run more pressure to reduce the side forces on the tag when performing sharp turns with the tag still down. The first tread on each side of the tread is designed to tear away during some failures. This is unlike traditional tire designs and why I encourage the extra pressure.

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Fratto
12-04-2019, 04:20 PM
This is the approach that I took since I have not located a scale that I could get each wheel position. I set up a spreadsheet where I could view changes in the side to side variance and then settled on 115 / 90 / 95 for the no slide CC.

I ran the steer at 110 for a couple of trips but it seems to ride better at the 115.

Ck2hans
12-04-2019, 05:02 PM
If you are ever passing through Orlando, FL JoSam's has a large drive on rack with individual wheel weight capability. Charged me $65.00

Any body have pictures of a Prevost with super singles? Just curious what it looks like.

Chuck

Gil_J
12-04-2019, 05:28 PM
Not a great picture. FWIW, I'm told Diamond Coach orders all of their X-3 shells with the optional 455 super singles.

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