Tire temps and pressures in summer

[rkymntsno]

Now that I have the EEZ TPMS, I need more info on how to monitor the tires. Coming back from our recent trip, the right rear tire got up to 108 degrees and about 97 psi. I called Discount Tire since they're the "experts" on tires, and asked how do I know if the tire is getting too hot and pressure is rising too much. The guy told me as long as the tire doesn't exceed the max psi. What? Max PSI on Goodyear Endurance on my 5er is 80 cold and that's what they recommend to put in them for running psi. So I'm supposed to only put 60 psi and let them heat up to 80 psi? I don't think so. So what temps and psi do the tires have to reach before I get concerned? Anybody know?

[GHen]

Lots of discussion on this topic. Yes, 80 pounds is the “cold” max pressure and they will get into the 90’s quickly even on a cool day.

I think I have my tpms set to 98 pounds and 158 degrees.

[Jim Smyth]

My TV and my trailer are both 80 psi max cold. I dont have monitoring on the trailer so I use my TV TPMS as a guide. Before the day gets going I like to keep the cold tire pressures around 74-75psi. This way when they heat up they are not too much higher than 80. To me 80 is 80 and I dont like pressing limits ever. Highest they usually get is around 83-84psi. I normally see about a 7-8psi rise in pressure.

[Bassdogs]

Originally Posted by Jim Smyth

My TV and my trailer are both 80 psi max cold. I dont have monitoring on the trailer so I use my TV TPMS as a guide. Before the day gets going I like to keep the cold tire pressures around 74-75psi. This way when they heat up they are not too much higher than 80. To me 80 is 80 and I dont like pressing limits ever. Highest they usually get is around 83-84psi. I normally see about a 7-8psi rise in pressure.

Read the label on the tire sidewall. 80 may be 80 but its what it says along with the number and that is cold temp. Tire manufacturers know a tire temp will rise as it rolls and that will cause an increase in PSI. The max cold limit is not the max tire limit at road speed. If you start out low, a couple things can happen. One is that the tire sidewall will flex more as it rolls which will result in heat and can lead to tire failure. Second, lower psi will increase drag and negatively impact fuel mileage.

Trust the manufacturer rating and start at the max psi rating for optimal tire performance.

[RedHorse1]

I agree, inflate to the max pressure as found on the tires. Once you are rolling keep a gentle eye (the Bride, my navigator, does this task) and watch for pressure or temp out of line with the others. I think my TPMS will alarm at 135 deg.
Yesterday we drove from Houston to Austin and the air temps were abt 94. The Bride recalls seeing 107 for sure and maybe a little higher. We run our tires 110 psi cold and saw maybe 115 while underway.

Trailer weight, wind and sunshine all have an effect on temp and press. The sunny side tires are usually a little warmer.

[rkymntsno]

Originally Posted by RedHorse1

I agree, inflate to the max pressure as found on the tires. Once you are rolling keep a gentle eye (the Bride, my navigator, does this task) and watch for pressure or temp out of line with the others. I think my TPMS will alarm at 135 deg.
Yesterday we drove from Houston to Austin and the air temps were abt 94. The Bride recalls seeing 107 for sure and maybe a little higher. We run our tires 110 psi cold and saw maybe 115 while underway.

Trailer weight, wind and sunshine all have an effect on temp and press. The sunny side tires are usually a little warmer.

We were traveling this past Thursday and the outside air temps were about 94 going around Austin and into San Antonio. The right rear got the hottest at 108 where the others were 99 and below.

[norty1]

Mine set for 20 psi higher and 10 psi lower. Temperature is set for 157 deg.

[TCNashville]

Originally Posted by Bassdogs

Read the label on the tire sidewall. 80 may be 80 but its what it says along with the number and that is cold temp. Tire manufacturers know a tire temp will rise as it rolls and that will cause an increase in PSI. The max cold limit is not the max tire limit at road speed. If you start out low, a couple things can happen. One is that the tire sidewall will flex more as it rolls which will result in heat and can lead to tire failure. Second, lower psi will increase drag and negatively impact fuel mileage.

Trust the manufacturer rating and start at the max psi rating for optimal tire performance.

I wish everyone who had a tire psi question could read this post because this is exactly what you should do.

[Mopar_Earl]

Originally Posted by Jim Smyth

My TV and my trailer are both 80 psi max cold. I dont have monitoring on the trailer so I use my TV TPMS as a guide. Before the day gets going I like to keep the cold tire pressures around 74-75psi. This way when they heat up they are not too much higher than 80. To me 80 is 80 and I dont like pressing limits ever. Highest they usually get is around 83-84psi. I normally see about a 7-8psi rise in pressure.

Completely wrong! Your hot pressure is supposed to be higher. It's max pressure cold, not max cold and hot. Please read what the tire manufacturers have on their websites.


Earl

[AKRUEBBE]

Originally Posted by rkymntsno

Now that I have the EEZ TPMS, I need more info on how to monitor the tires. Coming back from our recent trip, the right rear tire got up to 108 degrees and about 97 psi. I called Discount Tire since they're the "experts" on tires, and asked how do I know if the tire is getting too hot and pressure is rising too much. The guy told me as long as the tire doesn't exceed the max psi. What? Max PSI on Goodyear Endurance on my 5er is 80 cold and that's what they recommend to put in them for running psi. So I'm supposed to only put 60 psi and let them heat up to 80 psi? I don't think so. So what temps and psi do the tires have to reach before I get concerned? Anybody know?

I have the EEZ TPMS also. Had it on my North Point for a year and then switched it to my Pinnacle. I have the max psi set at +20% or 96 psi. Have never been over 95 psi with the North Point. The last leg of our journey, with the Pinnacle and the TPMS set at the same parameters, my high pressure alarm went off on two of my tires (96psi). Never having had the alarm go off before scared the hell out of me. The temperatures were between 92 & 99. I contacted EEZ support and related the situation. He said that +20% is an industry "standard" but could very from tire to tire and RV to RV. With the Pinnacle being nearly 1,800 pounds heavier than my North Point, he suggested I increase the high pressure alarm point to 99 psi. The highest I've seen my temps was 110 degrees in 100 degree weather.

[GHen]

Here is another issue, If you don’t run max air pressure as listed on the tire you also do not have the max load available for that tire. The tire manufacturer will have a chart that will show load at different pressures.
This is just an example; if the tire at 80 pounds gives you 2500 pounds load, the same tire at 75 pounds may only give you 2000 pounds load, I’m camping so I don’t have the chart for my tires with me, so just an example.

[Jerry Burks]

What bothers me about the "xxx pressure cold" spec is that it does not mention how cold that is. Is that a spring day in Minneapolis or a nice summer day in Phoenix? Such a "cold" temperature range will already account for 20 psi difference or more.

So for my purposes I will assume that "cold" means about 60-70F before driving and I try to set the pressure to the Jayco specified 82psi (not the max load rated 110psi of the tires). On a warmer day I will use a little more pressure or less when colder. FWIW, this is not for a fifth wheel but a F53 based class A.

[Mopar_Earl]

Originally Posted by Jerry Burks

What bothers me about the "xxx pressure cold" spec is that it does not mention how cold that is. Is that a spring day in Minneapolis or a nice summer day in Phoenix? Such a "cold" temperature range will already account for 20 psi difference or more.

So for my purposes I will assume that "cold" means about 60-70F before driving and I try to set the pressure to the Jayco specified 82psi (not the max load rated 110psi of the tires). On a warmer day I will use a little more pressure or less when colder. FWIW, this is not for a fifth wheel but a F53 based class A.

Cold is ambient temperature, not driven. That's why they don't say X temperature. Actual temperature doesn't matter as you inflate when the tire is cold (ambient). Altitude also effects tire pressure.


Earl

[Rock]

Tires cold at 105 running in summer 120 and temp up to 128. All will vary 5-10 on temp and psi. Rear on truck 80 cold 95 running in summer and temps 115-120

[jasum]

Originally Posted by Bassdogs

Read the label on the tire sidewall. 80 may be 80 but its what it says along with the number and that is cold temp. Tire manufacturers know a tire temp will rise as it rolls and that will cause an increase in PSI. The max cold limit is not the max tire limit at road speed. If you start out low, a couple things can happen. One is that the tire sidewall will flex more as it rolls which will result in heat and can lead to tire failure. Second, lower psi will increase drag and negatively impact fuel mileage.



Trust the manufacturer rating and start at the max psi rating for optimal tire performance.

X2

[jasum]

Originally Posted by Mopar_Earl

Cold is ambient temperature, not driven. That's why they don't say X temperature. Actual temperature doesn't matter as you inflate when the tire is cold (ambient). Altitude also effects tire pressure.





Earl

X2

[RedHorse1]

Originally Posted by rkymntsno

We were traveling this past Thursday and the outside air temps were about 94 going around Austin and into San Antonio. The right rear got the hottest at 108 where the others were 99 and below.

A 10 deg difference between the hottest tire and the other 3 sounds a bit much. Could be a brake dragging or a bearing running hot. Next time you see that much difference find a safe place to pull over and feel the hubs to see if the heat is coming from one of those sources. Might also be the way the TT is loaded or something with the suspension, a visual inspection of the spring hangers and spring to axle U bolts to make sure they look ok.

[rkymntsno]

Originally Posted by RedHorse1

A 10 deg difference between the hottest tire and the other 3 sounds a bit much. Could be a brake dragging or a bearing running hot. Next time you see that much difference find a safe place to pull over and feel the hubs to see if the heat is coming from one of those sources. Might also be the way the TT is loaded or something with the suspension, a visual inspection of the spring hangers and spring to axle U bolts to make sure they look ok.

Ok, will do. I have a thermal gun just for that purpose but didn't mess with it as we were getting close to home and worn out. Usually when it happens right? This stuff's all new to me and I'm trying to learn it. I take it in Tuesday and will talk to the service dept about it also. Thanks.

[wags999]

I guess were never suppose to have an RV since we live in Phoenix...where ambient air temps can easily be 115. Road temps can be over 140 degrees, Never had an issues. Maybe my tires are defective, much like my guns...tires never exploded and my guns never shot anyone...think I need smarter tires and guns?

[Marmot]

Check and adjust the pressure to 80psi first thing in the morning before driving and before the sun hits the tires. Don’t worry or concern yourself about the rise in temp and pressure while driving-tires are designed and built to withstand the changes. Your monitoring system is mostly useful to catch a tire going flat.