Tire pressures experience

[Rustymayes]

I set my tire pressure to the recommended figures on the placard in the coach cold. Every trip, with in a half hour on the road, the tire pressure and temperature warning bells go off and the information screen shows which tires exceeded the temp target. The dealer warned me about this issue and said not to worry about it but is a PITA to constantly be cancelling the screen as I drive. This is on a 2022 Dutch Star 4081 with a Tag Axel. The warnings are mostly limited to the rear tires, not the fronts. Has anyone dealt with this and found a reasonable solution? Running lower pressure I would think would increase temps so running higher pressure might be a solution as I am running way lower than the max marked on the tires.

 

[jagpot]

Dealt with this same problem. Finally sat down last trip to take care of this. Put all tires at recommended pressure. Set high PSI at 20% more and Low at 10% deviation on the Trip tix monitor. Set temps at 160. Have not had a beep since.

 

[scottramer]

First, never go by the placard. That is only the max pressure the tires can run at. The proper procedure is to weight the coach the follow the pressure chart published by Michelin assuming you have Michelin Tires. And it is correct that the pressure when the tires get hot will go up as much as 20 psi, that is normal.

 

[Rustymayes]

Dealt with this same problem. Finally sat down last trip to take care of this. Put all tires at recommended pressure. Set high PSI at 20% more and Low at 10% deviation on the Trip tix monitor. Set temps at 160. Have not had a beep since.

I will look into doing just that!
Thanks

 

[Swipular]

First, never go by the placard. That is only the max pressure the tires can run at. The proper procedure is to weight the coach the follow the pressure chart published by Michelin assuming you have Michelin Tires. And it is correct that the pressure when the tires get hot will go up as much as 20 psi, that is normal.

Scott is correct. Go by the manufacturers suggested pressure by weight. A four corner weight is best but if all you can get is a standard axle weight that's better than nothing. Your coach will ride a lot better with the tires set at the proper pressure also.

 

[Rich W.]

You should definitely weigh the coach, preferably each side of each axle, then use the higher weight of each axle for both tires on that axle. Then set your TPMS to alarm at 10 psi low to account for colder days, and 25psi high to account for warming while driving. Find your correct tire pressure after weighing in this publication:

https://rvsafety.com/images/pdf/michelinloadandinflationrvtruck.pdf

Here’s some bedtime reading:

https://www.michelinb2b.com/wps/b2bcontent/PDF/RV_Tires_Brochure.pdf

https://tiretraker.com/michelin.pdf

 

[frogsme]

I had the same problem with my 2022 DS 4081. My rear tires were set at 85 psi and the fronts at 115. This caused the rears to always be high on pressure and temp. I raised the rear to 95 psi, temp problem went away but still had high pressure because TPMS set at 85. Recent trip to Spartan, had them reset the rear TPMS to 95 and my problems went away. When I can I will get a 4 corner weight and go from there

 

[Rustymayes]

My freightliner manual says to follow instructions in the Valor TPMS manual to set the temp warning limits. Has anyone found instructions? I don't even know if we have Valor TPMS on the 2022 DS 4081 since the pressures are displayed on the Opti View instrument panel. There is a lot of information in the Freight Liner manual but it si hard to really find what I am looking for. In terms of weighing the coach, where do you even go to do that? I am thinking of using my aircraft scale load cells on each axel to get a pretty good idea.

 

[Rich W.]

I like to stop at closed scales. I’ve found that in Ca when they close the scales they also turn them off, but in other western states (Nevada, Oregon, Washington) the scales are usually on. There is also the certified scales truckers use but you can’t get four corner weights in those - it’s just pull on, stop, pull off. So when I’m traveling I look for scales that are on but not in use so I don’t aggravate anyone and I can take my time and weigh the coach however I want.

One of my favorites is in Oregon north of Winnemucca at the intersection of 95 and 78 - always on and never anyone there. But your method sounds good - most people don’t have those lying around. Something like this?

 

[sheridany]

most people don’t have those lying around. Something like this?

I do. four of them.

 

[Rustymayes]

I have a set of those but they are only rated to 3500 for each pad. I have an old air force set of load cells that mount on jacks. I have some 9500 lb helicopter jacks that may fit under the axles of the rig so I can weight one at a time.

 

[Rustymayes]

I do. four of them.

What are yours rated for?

 

[Joe Dutchstar]

If you can get past the "Persona" of this guy, the information he provides is useful for using a CAT scale for a four corner weight. Skip to 3:00 for the CAT scale section.

 

[Rustymayes]

Now my wheels are turning on how to build a fixture to use my load cells. I have a buddy with an amazing fab shop that will help me. I figure I can use my jacks to raise the coach to slide the scales under each wheel and block the others up to keep the coach level. Doing the rears with the tag axel would be problematic using a truck scale. As I am thinking of all of this though I can't help but wonder how important it really is. What is the tangible benefit of knowing the exact weight of each corner when it changes constantly as you cruise and burn fuel and carry different water levels, gear and passengers? There are just so many variables to consider. I think of trucks for instance. Their loads vary wildly, are the truckers adjusting their pressures based on their load?

 

[Rich W.]

Its not crucial and you can use 1/2 the axle weight plus 10% to account for variation. Doing four corner weighing allows you to use the lowest pressure possible allowing the best ride while remaining safe. On trucks its not that much of an issue because a tire failure usually just means a little down time - a coach a tire failure can be disastrous. Which is one reason we don’t run retreads either. I would think truckers run at max pressure all the time to allow maximum loads and they don’t care if it rides rough when empty or lightly loaded. Also note that only the RV inflation charts have data for individual tires. The truck charts are per axle.

I would say that only a small percentage of RV owners weight all corners, most don’t weigh at all, and probably the vast majority don’t even think about it. Its just us fanatics that go to such lengths. But since Michelin publishes inflation charts for RV usage, I try to get as close as possible. You have a smoother ride with IFS so its less of an issue for you.