How does over inflation affect wandering?

BruceMc wrote
I'd suggest trying it & find out what happens. I run 60 to 65 in the fronts and 65 - 70 in the rear, where the inflation charts suggest 55 for my weights.
If it wanders too much, it's easy to pull over and shed some PSI.

I started out running 80 all the way around, but after just a few miles, decided I didn't like riding in an old lumberwagon. 60/65 seems to be the sweet spot for the Four Winds. I didn't have any wandering problems, as the ford is always light in the frontend and had to be herded between the fencerows.

We are picking up our new Sunseeker in a little over an hour from now... so I'll have a whole new machine to learn & tinker on!


Thanks, that's the psi my chart says to use. There was 70 psi in the front and should be 60-65 or closer to 63. Will try!
And congratulations on your new Sunseeker! I have the big Brother Forester 2701DS. Yes, new learning curve and moving everything over. Took 12+ years to get our Winnebago the way we wanted it and trying to get the Forester like that in a few weeks doesn't work.

BTW- check see if your new nav radio has the Q22015 update. Some have Q4 2012. You can update them within 30 days of activation. If you have a problem send me a PM

High pressure in the rear tires should make the sidewalls stiffer and better able to withstand input from the trailer. Probably one of the more dangerous conditions is a low rear tire that allows the rear of the tow vehicle to shift from side to side. As far as rear trailer loading, that figures into a nasty dynamics issue know as polar moment of inertia. The further a given load is from the axle location the more impact it has on the stability of the trailer.

I think the front overinflation contributes to the wandering. I doubt the rear contributes much if any to it. Rear overinflation is detrimental to ride quality-as the isolation of the springs, bushings and body mounts tends not to be the best. IMO if you don't mind the ride pump up the rear up to the sidewall limit.

Harvard may have input here, but it is possible the longer contact patch of the front tires due to lower pressure may increase the effect of caster and have better return to center. If you've ever driven a non power steering car you'll notice lower tire pressure increases steering effort, increases return to center, and is less sensitive (twitchy?) on center.

The longer I've had my motorhome the closer I come to the exact inflation table pressures-with little or no cushion. I like the improved rear ride and the better steering feel. If I'm trying to generate a safety cushion it is by keeping the speeds below 65 MPH and not seeking out the hottest of the hot pavement. Running pressure table spec is running to spec. There's no reason to carry 75 to 80 PSI in the tires when the front tires are specified to carry 50 with the load.

The higher the pressure, the smaller the tire foot print on the road, which equates to wandering, rougher ride. On a Class C, try 72 up front and 80 in rear.

I'd suggest trying it & find out what happens. I run 60 to 65 in the fronts and 65 - 70 in the rear, where the inflation charts suggest 55 for my weights.
If it wanders too much, it's easy to pull over and shed some PSI.

I started out running 80 all the way around, but after just a few miles, decided I didn't like riding in an old lumberwagon. 60/65 seems to be the sweet spot for the Four Winds. I didn't have any wandering problems, as the ford is always light in the frontend and had to be herded between the fencerows.

We are picking up our new Sunseeker in a little over an hour from now... so I'll have a whole new machine to learn & tinker on!