Needing tire psi/weight numbers verified

[US1]

Just had my RV weighed in order to adj tire psi

Class A 29', full gas.
Sumitomos 225/70R19.5 tire, F rating, Steer tires all 4 corners

Scales did not allow for 4 corner weighing
Front axle 5000#
Rear axle 8450#

From what I understand on the tire psi chart, my actual axle weights are less than the lowest choice ratings on the scale of Fronts 2755lb, and rear dual of 2600lb. In those cases, 65psi for all tires as the chart doesn't go lower.

My coach placard says fronts 70, rear 60.

So would you recommend I just use the placard, or drop my front down to 65, or even 60? Thinking the 70 on front will give a harsher ride being a tad over inflated and leading to tire wear)
Thanks

[Gary RVRoamer]

The psi in the tables is the minimum necessary to support that weight, so it is advisable to go a bit higher to allow for the possibility of some extra load in the future and for days when the weather is colder and tire pressure drops. You also need some allowance for the likelihood that one side of the axle is heavier than the others (carries more than 50% of the weight. Generally, an additional 5 or 10 psi provides some margin to cover these things. And never go under the minimum shown on the table for your tire size.


The 65 psi minimum gives you some extra load margin, but I'd go with 70 psi on the front unless you find the ride harsh or the steering too sensitive. Or maybe split the difference at 67-68 psi. 65 psi is fine for the rear and provides plenty of extra weight carrying capacity in case you ever load up or encounter cold weather.

[US1]

Thank You Gary

[chunker]

You could get a 4 corner weight sort of. If there is room beside the scales to park half on, you can run a second weighing and do the math. Not all scales have room but the flying J near me is clear on the right, left side has posts. I weighed the motorhome that way and found the right side was 700# heavier than the left. That method may not be 100% accurate due to sloping ground beside the scales, but in my case, it was level so close enough.

I recently weighed my truck loaded for travel and when the new toy hauler comes in, I'll weigh it empty that way.