Correct tire pressure

[Dippytwo]

I’m sure this has been covered before, but I want to make sure I’m running the correct pressure in my tires. I have the Goodyear 245/70R 19.5 with max pressure 110 psi. My Thor sticker says to run at 82 psi (all tires), the RV shop that I got my CHF done at says to run at 110 psi since that’s the max load on the tires. I took my MH to a CAT scale, the front axle is 6020 lb, rear axle 9770 lb, (total 15790 lb). I looked at that Goodyear chart and not sure if I’m reading it right, the best I can figure out is they are telling me to run at 110 psi. So, 82 psi or 110 psi?

[JamieGeek]

Just read the Goodyear tire loading chart (pdf).

[Dippytwo]

Yep, I read that. It didn't clear it up for me.

[mountainsam]

I have always been told, on my pickups and trailers anyway, to always fill to the recommended pressure on the vehicle sticker. Thats where mine will be set at. Check the wear periodically. I also carry an infrared thermometer and check temps of tires at fueling stops.

[EA37TS]

Originally Posted by Dippytwo

I’m sure this has been covered before, but I want to make sure I’m running the correct pressure in my tires. I have the Goodyear 245/70R 19.5 with max pressure 110 psi. My Thor sticker says to run at 82 psi (all tires), the RV shop that I got my CHF done at says to run at 110 psi since that’s the max load on the tires. I took my MH to a CAT scale, the front axle is 6020 lb, rear axle 9770 lb, (total 15790 lb). I looked at that Goodyear chart and not sure if I’m reading it right, the best I can figure out is they are telling me to run at 110 psi. So, 82 psi or 110 psi?

The tire charts list weight per tire location (corner weights). Take your axle weight and divide by 2. Your front will be 3010 and rear will be 4885. Looking at the Goodyear chart your front pressure for single wheel should be 80 PSI and the rear for dual should be 110.

You might want to verify the weight rating of your tires because your rear corner weights are not listed on the Goodyear chart. You may not have an adequate tire for the rear axle weight (optimal words being "may not").

[Chance]

The chart appears to me to show allowable load per tire. As such, it looks to me like 80 PSI would cover the minimum required load at front for singles, or at rear with duals as the vehicle was weighed.

The sticker at 82 PSI for all tires should cover higher weight ratings of axles -- which is the normal recommendation. I'd personally stick with the recommended 82 PSI.

[Thor29.3inAZ]

I have the same tires on our Thor A.C.E. 29.3. Make sure you have done a front end alignment. The placard is what you should run your tire pressure. I had a tire guy say to make sure you don't over heat the tires, you need to run them at max (110 psi). So I tried keeping the pressure @ 110 psi. IT ABSOLUTELY RUINED THE RIDE AND HANDLING!!!! I brought the pressure back down to the 85 listed on our couches recommendation plate. It is now one of the best riding RV I have ridden in or driven. Our weighs the same as yours too. I'm not sure why some think you need to run tire pressure so high it ruins everything you want in a ride for your RV. Goodyear has also mentioned somewhere in their web site, the tires can be run as low as 75 psi without damage. Just saying.....

[Hudsoner]

Originally Posted by Thor29.3inAZ

I had a tire guy say to make sure you don't over heat the tires, you need to run them at max (110 psi). .....

Many of the tire guys have no clue what they are talking about. As I mentined in other threats, my son is a certified master mechanic at the largest Ford dealer in the state. He has some "tire guys" on his crew. His tire guys (and he says most of the tire guys at any company) don't know anything more about tires than how to take them off, put them on and balance them. They are no tire or truck experts. My son calls them tire monkeys, like the lube techs are lube monkeys.
Listen to your certified mechanic or follow the tables of the tire manufacturer, they know way more about tires and their proper application than the "tire guys" in any given shop do!

[jadatis]

Originally Posted by Dippytwo

I’m sure this has been covered before, but I want to make sure I’m running the correct pressure in my tires. I have the Goodyear 245/70R 19.5 with max pressure 110 psi. My Thor sticker says to run at 82 psi (all tires), the RV shop that I got my CHF done at says to run at 110 psi since that’s the max load on the tires. I took my MH to a CAT scale, the front axle is 6020 lb, rear axle 9770 lb, (total 15790 lb). I looked at that Goodyear chart and not sure if I’m reading it right, the best I can figure out is they are telling me to run at 110 psi. So, 82 psi or 110 psi?

Call myself "Pigheaded Dutch Selfdeclared Tirepressure-specialist" nowadays, and story began when I got hold of the official European calculation and went running with it, got much wiser in time, and google dayly for tire/tyre-pressure to see if I can help ( or ventilate my ideas).

Made a multilingual motorhome-tirepressure-calculator with excell , and filled your data.
First looked at the link given of Goodyear to determine the maximum load of your tires.

Was the G-load/LRG version of the list, and 4540lbs Single and 4410 lbs Dual per tire AT 110 psi. this I searched back to be Loadindex 133/132 wich is stange because mostly dual 2 lower then Single, and then even in American system sometimes 4 LI steps lower for dual.
so adjusted it Dual to LI 131 / 4300 lbs maxload.

Then filled in in my made calculator wich first adds 10% reserve to the weighed loads and then calculates the pressure with my own determined extra save formula ( even gives higher pressure then the European formula, wich on its turn is saver then the American calculation.
This allows to go verry low in the pressure with still the same deflection of tire as when maximum load AT AT-pressure on tire, wich is the goal of all calculations.

Gave advice of Front ( single load axle) of 79 psi ( make it 80 psi) and Rear (dual-axle so 4 tires on the axle) of 67 psi ( make it 70 psi).

But how did you weigh, was it with all the persons and things in the motorhome, so as you use it in practice, or empty , or some persons not inside, or minimal water or fuel in tanks. Then you shoud estimate what comes to that "empty " weight , and I can help you with that too, but the outcome will be less acurate, as when weighed fully loaded .

Then these advice pressure would be to low, so still possible damage to tires by overheating.

Greatings from the Netherlands
( ja dat is) Peter

[Dippytwo]

OK, so I called Goodyear Tire and gave them my weights and she looked at the chart. She said both front and rear will be at 80 psi. Basically she said you divide the weight by 2 for the front axle and divide by 4 for the rear axle to get the numbers. I told her that Thor recommends 82 psi and she said that’s fine.

[Hudsoner]

Originally Posted by jadatis

Call myself "Pigheaded Dutch Selfdeclared Tirepressure-specialist" nowadays, and story began when I got hold of the official European calculation and went running with it, got much wiser in time, and google dayly for tire/tyre-pressure to see if I can help ( or ventilate my ideas).

Made a multilingual motorhome-tirepressure-calculator with excell , and filled your data.
First looked at the link given of Goodyear to determine the maximum load of your tires.

Was the G-load/LRG version of the list, and 4540lbs Single and 4410 lbs Dual per tire AT 110 psi. this I searched back to be Loadindex 133/132 wich is stange because mostly dual 2 lower then Single, and then even in American system sometimes 4 LI steps lower for dual.
so adjusted it Dual to LI 131 / 4300 lbs maxload.

Then filled in in my made calculator wich first adds 10% reserve to the weighed loads and then calculates the pressure with my own determined extra save formula ( even gives higher pressure then the European formula, wich on its turn is saver then the American calculation.
This allows to go verry low in the pressure with still the same deflection of tire as when maximum load AT AT-pressure on tire, wich is the goal of all calculations.

Gave advice of Front ( single load axle) of 79 psi ( make it 80 psi) and Rear (dual-axle so 4 tires on the axle) of 67 psi ( make it 70 psi).

But how did you weigh, was it with all the persons and things in the motorhome, so as you use it in practice, or empty , or some persons not inside, or minimal water or fuel in tanks. Then you shoud estimate what comes to that "empty " weight , and I can help you with that too, but the outcome will be less acurate, as when weighed fully loaded .

Then these advice pressure would be to low, so still possible damage to tires by overheating.

Greatings from the Netherlands
( ja dat is) Peter

Goeden dag Peter
Goede bijdrage. Maar einiiges in de bijdrage is verloren gegaan in de vertaling. Kunt je schrijven de artikelen in Duits? Google Translate is beter met de Duistse taal dan bij de Nederlandse. Ik heb geconstateered dat Google Translate heeft meer datapunten voor de Duitse taal.
Met vriendelijke groet van Dick
(die heeft gewoond in Susteren in de Selkant, en sinds 1968 ben ik daar weg, en in de VS)