Does tire pressure drastically affect crosswind stability?

gperky wrote:
One of the biggest spoilers of our travelling enjoyment is the spooky handling of our moho in the southwestern desert winds. Gusts of crosswinds can literally make it change lanes if they are strong. It doesn't lean much, but it moves sideways. I run the tire pressure on our 30ft. gasser A at 75 to 80 psi for a smoother and quieter ride. Do you know if increasing the pressure by 10 or 20 psi would make a big improvement in the stability? The tires are 245 70R 19.5.

Look on the side of your tires for "max pressure" psi the tire is designed for. Then air the tires to the max. I run my Good Year "G" rated tires at 110 psi.

I've no experience with your rig, so can't answer directly. But back in my youth I raced sports cars, and I know that tire pressure makes all the difference in the world with how a vehicle handles, with under inflated tires causing just the problem you discribe. I also know this from driving a truck full of firewood that I borrowed from a friend. On the way to get the firewood, it handled fine. On the way back with the wood aboard, we were all over the road until I stopped at a gas station to pump up the tires. Then we were fine again.

how fast are you driving?

You don't mention what kind of RV you have. Is it on the F53 and if so have you done the CHF? That will help sway a lot. Secondly, have you weighed your rig and adjusted PSI properly? I wouldn't play with PSI unless you had weights to justify it. In the end, there are some things you can do but you are driving a billboard. Wind will push it. More wind you need to travel at lower speed to reduce the impact on steering.

Probably not. But if the max. tire rating allows that much pressure, try it.

But then you are driving a big barn door on wheels. All vehicles that size have some problems in high cross winds. The solution is to stop until those extreme conditions subside.

Might be worth while to have the steering and suspension checked though.

The people I have ridden with that have the most trouble with winds are drivers who over-correct and make the problem worse than it is.

Have you weighed it?

I have experimented with pressures from 75 to 100 and get the most stability at 80. Same tire size. Load inflation chart says 75 for my weight.

Lower pressure it slows the response to steering inputs. Higher gets more reactive to road imperfections and skittish as the contact patch shrinks.

YMMV