Average tire temp above ambient

[SteveSueMac]

I've seen some conflicting information in this and other forums regarding tire temperature above ambient.

With the friction of the tire against the road, which itself is probably higher than ambient air temperatures, I'm wondering what range is acceptable for tire temps.

With my TPMS system, I'm seeing an average of 30 degrees above ambient (consistently over the 4 trailer tires) This doesn't bother me when ambient temps are 70 or below, but above 70, my trailer tires start registering triple digits. I've seen them get as high as 120 during 90+ degree weather.

My TPMS manufacturer recommends a warning at 154 (I believe) as much above that (180? ) is where failure occurs.

Any thoughts? Thanks!

[SteveH]

I think tire temperature will be depend on lots of variables like speed, load, air pressure, direct sun light, etc., so there's probably no set or predictable temperature above ambient.


I can tell you on our last trip, I saw temps from 10 to 15 degrees above ambient with 16" load range E LT tires inflated to 70 pounds, and running an average of 65 MPH.

[Aviator]

I usually see about 30f degrees above ambient. It is a combination of road temp plus friction. I am not concerned as long as it stays below 140f. Yes, tires,will fail at about 180f

[DKB_SATX]

The ST tires that were on my Argosy when I bought it (Carlisle Radial Trails) ran about 25F above ambient (as measured with an infrared thermometer).

The Michelin LTXs I replaced the Carlisles with when they aged out run about half that... 10-15F above ambient.

[ghaynes755]

15" Marathons with the TST TPMS system are usually 30 degrees above OAT running at 65mph.

[Tireman9]

Tire operating temperature primarily comes from the internal molecular friction of bending the rubber. The temperature will increase until the heat generation rate matches the cooling from the surrounding air and heat flow through the internal air in the tire to the wheel and to outside air.

Multi-axle trailers should use the tire sidewall pressure as the cold "set" pressure.
I have written in my blog about how this max pressure will keep the rubber flexing and internal shear forces as low as possible for the load you are running.

Cooler running and storage under white tire covers also will lower the tire aging rate which means more service before possible failure.

There is no way you can use the info from a different RV to know what the "correct" answer is for your tires. Speed, inflation, load, air flow, tread depth type of wheel (steel or aluminum) even wheel design can all impact the steady state running temperature.

The 150 - 160F range for TPM warning is reasonable but you should never see that if you are running less than 85% of the maximim tire load and are running the tire max inflation.

[CapriRacer]

A couple of thoughts:

First is that there is a difference between measuring the surface temperature of a tire (by using an infrared thermometer) and the temperature of the air chamber. Don't confuse the 2.

Second a 30°F build up (about 10% pressure buildup) is a good operating number. Concern should be paid if the values gets over either of those.

[andreasduess]

I do a quick touch check on my tires after towing, so far from accurate, but I can say that 30º above ambient seems high to me.

Then again, on the triple axles the tire load is relatively low, so they can, and should, be run at slightly lower pressure.

[SteveSueMac]

Originally Posted by CapriRacer

A couple of thoughts:

First is that there is a difference between measuring the surface temperature of a tire (by using an infrared thermometer) and the temperature of the air chamber. Don't confuse the 2.

Second a 30°F build up (about 10% pressure buildup) is a good operating number. Concern should be paid if the values gets over either of those.

Thanks - those are both what I'm seeing - about 30 degrees F above ambient and about 10% increase in pressure (consistently). My TV TPMS doesn't show temp, only pressure and those tend to rise about 10% as well.

Thanks for the insights! Very helpful!

[Tireman9]

Originally Posted by andreasduess

I do a quick touch check on my tires after towing, so far from accurate, but I can say that 30º above ambient seems high to me.

Then again, on the triple axles the tire load is relatively low, so they can, and should, be run at slightly lower pressure.

With over half on 5th wheel RVs having one or more tires overloaded I am not sure you can be confident a triple axle is not overloaded.
Load is never balanced equally between all axles and side to side on all axles.
Many times there are unbalance loads of over 500#.

Internal tire structure temperatur can run 20 to 60F above ambient depending on the many variables of load, inflation speed, type of wheel etc.