What air pressure would you run

[gb76087]

Took and had my Fleetwood 34N weighed before leaving on a trip the other day. It was going to be a short 4 day trip, so maybe not completely maxxed out on the weight, but was a least 50% loaded. The scales showed front axle at 6400 lbs., rear axle at 11,900 lbs, and trailer axle(toad) at 4340 lbs. The MH is running Michelin 235x80x22.5 tires. According to Michelin's website, single axle, 3470 lbs. and dual axle, 6320 lbs. should be at 70 psi. I am under those weights and am not sure I want to be running with anything less than 70 psi, in fact, not sure I would even want to run at 70 psi. What am am I missing and what psi would you be running?

[ct1964ups]

gb76087 wrote:
Took and had my Fleetwood 34N weighed before leaving on a trip the other day. It was going to be a short 4 day trip, so maybe not completely maxxed out on the weight, but was a least 50% loaded. The scales showed front axle at 6400 lbs., rear axle at 11,900 lbs, and trailer axle(toad) at 4340 lbs. The MH is running Michelin 235x80x22.5 tires. According to Michelin's website, single axle, 3470 lbs. and dual axle, 6320 lbs. should be at 70 psi. I am under those weights and am not sure I want to be running with anything less than 70 psi, in fact, not sure I would even want to run at 70 psi. What am am I missing and what psi would you be running?

I've had 6 motorhomes.....the last one I traded was a 2004 MADP...I ran the fronts at 120 lbs...the drive axle and tag...I ran @ 105 lbs..the OE tires went to 85,000 miles and I only took them off because of age...7 yrs old....I replaced them @ Spartan...they have a book of pictures with all different tire wear...mine showed as over the road..bus or truck....perfect wear....high mileage use.....
Granted the ride may have been harder ...but at $800 a tire it was worth it..Chuck

[JimM68]

the bear II wrote:
I always run at PSI shown on the tire. If it shows 90lbs I run 90lbs. That way I don't have to worry about loads and correct tire pressure.

The number on the tire means (read carefully) the lowest permitted pressure to run the maximum permitted load.

This is a totally meaningless number, unless your load happens to be the max the tire can carry and you want the best softest ride possible.

You can run a higher pressure if you prefer, and if you are at a lower load you may run a lower pressure.

[wa8yxm]

the bear II wrote:
I always run at PSI shown on the tire. If it shows 90lbs I run 90lbs. That way I don't have to worry about loads and correct tire pressure.

The problem with that is this: PSI should balance load Other wise your tirs are like the letter U or like a top hat ^ In your case the U, only the center of the tread contacts the road.

This results in a rougher ride, and reduced handling epically in bad weather.

Low pressure gets the top hat, and though a softer ride, Reduced tire life (By the way using only half the tread also reduces tire life) increased chance of side wall blow out (At least you do not have that) and reduced handling on ALL roads.

You should run the proper pressure.

To the Original POster.. I'd go with 70 PSI based on the charts, you are not that much "underweight" and many folks do like to add 5 PSI.

[J-Rooster]

I'm running the same tire and wheel size as you! My Winnebago and Michelin manual said to run 85 lbs. psi rear and 90 lbs. psi front. That didn't work for me rear tire squirm! I experimented different tire pressures for 6 months and I found that 100 lbs psi. worked on all the tires. At 100 lbs. psi I was able to get 10 years of tire wear out of that set of tires and I have one year on my second set. Good Luck to you!

[rk911]

running higher than needed pressure in tires can equal a very rough ride as well as premature wear and handling issues...or so i'm told by a tire guy I trust. to each their own but the tire inflation tables were created for a reason.

[CA_Traveler]

BTW You should also weigh one side so that you'll know the weigh for each corner. You then use the heaviest side weight for the axle to determine the inflation for all tires on the axle. This is also useful for balancing side to side weight.

[CA_Traveler]

I use 5 over on the rear and 10 over on the front. Until you can weigh it fully loaded included water, fuel and propane, I'd run 10-15 over the Michelin table.

[ArchHoagland]

I run 5lb over what Michelin recommends for my weight. 85lb is their recommendation and I run 90lb.

Over inflating, especially running the maximum stated on the tire, causes two problems.

A harsh ride and a tendency to wander a bit.

[the_bear_II]

I always run at PSI shown on the tire. If it shows 90lbs I run 90lbs. That way I don't have to worry about loads and correct tire pressure.

[gb76087]

Forgot to mention that I am currently running 90 to 100 psi.

[rk911]

gb76087 wrote:
Took and had my Fleetwood 34N weighed before leaving on a trip the other day. It was going to be a short 4 day trip, so maybe not completely maxxed out on the weight, but was a least 50% loaded. The scales showed front axle at 6400 lbs., rear axle at 11,900 lbs, and trailer axle(toad) at 4340 lbs. The MH is running Michelin 235x80x22.5 tires. According to Michelin's website, single axle, 3470 lbs. and dual axle, 6320 lbs. should be at 70 psi. I am under those weights and am not sure I want to be running with anything less than 70 psi, in fact, not sure I would even want to run at 70 psi. What am am I missing and what psi would you be running?

you should be at 70-psi at a minimum. minimum pressure for the indicated weight.