Tire Physics - RV-Dreams Community Forum

pkhalin · RV-Dreams Family Member

Tire Physics

Terry and Jo · RV-Dreams Family Member

Paul and Kim,

Sorry, but no physics from me. I flunked physics in high school.

If a tire is under-inflated, it will cause the tire to have uneven wear and with extra flex, it may contribute to overheating of the tire. That overheating can lead to the blowouts. Will a tire at 100 to 125 lbs psi have a more explosive blowout? Without a doubt, it will, but with proper maintenance of the tires and especially making sure the pressure is correct, they will last a lot longer.

I'd also like to point out that in your search for tires for RV's, try to get tires that are NOT made in China. On a number of forums, those tires tend to be referred to as "China-bombs." Also, research the different tires as to their weight capacities based on the weight they are carrying.

Terry

pkhalin · RV-Dreams Family Member

Thanks, Terry. Makes sense. And it was physics enough for me.

I do remember reading about the China tires. We'll see what we can avoid.

Thanks again.

TRAILERKING · RV-Dreams Family Member

Lot's of ply=Lots of PSI

Just like Terry said......
Usually under inflated=fail
Always check and maintain pressures.
Tires are usually the most neglected and overlooked.

And yes........Stay away from the Chinesium Line.

FastEagle · RV-Dreams Family Member

I’m often misunderstood when I write about tires for Motor Home RVs. Many are very large and heavy and use large RV or truck tires. So owners use the larger tire references from truck/RV tire data books.

Motor Home RV tires - regardless of vehicle size or tire size - are fitted according to Federal Motor Vehicle Safety Standards. FMVSS 571.120 outlines the fitment for Motor Home tires. Accordingly the correct tire inflation pressures are set by the vehicle manufacturer and are depicted on the vehicle’s certification label and in it’s owner’s manual. Tire industry standards never recommend using less inflation pressures than those found on the certification label. Replacement tires that are plus sized from the OE tires are required to have their inflation pressures set at a value that will equal or exceed the load capacity provided by the OE tires.

Tire pressure increases due to the vehicle’s speed are partially dissipated by a process called thermal equilibrium. The tire industry has accounted for those pressure increases. Once you learn what is normal for your tires you will be able to determine when one or more are abnormally high.

Here are a couple of links to very good information about inflation pressures for your Motor Home RV tires. Note that the Firestone reference has in bold letters not to use less inflation pressures than what is depicted on the vehicle’s certification label.

http://toyotires.com/sites/default/files/page-files/RV_tire_safety.pdf

http://www.trucktires.com/bridgestone/us_eng/press/zip/WeighForm.pdf

FastEagle

-- Edited by FastEagle on Tuesday 10th of March 2015 09:44:04 PM

dianneandsteve · RV-Dreams Family Member

I assume your Montana came with Goodyear Marathon tires as did mine. As Terry said these are known as China-bombs! If you haven't already changed them out you should ASAP. It seems that most on the Montana's owners forum have upgraded to the Goodyear G614 G rated tire that allows you to use your old wheels. On this forum it seems that most recommend going to the Goodyear G114 H rated, 125 psi tire, however this requires upgrading your wheels to 17.5". I went with the G114 upgrade from Trailer Tires and Wheels and now have full confidence when traveling that I never had before!

Safe travels!