Trailer tire pressure in the hot summer

[911golf]

Hello. I am sure this has been asked and I apologize if I am in the wrong section. Do you keep your tires at max pressure during the hot summer? My tires are 50 PSI cold. In the morning I plan to check pressure while it is mild out but then do I pump them to 50, knowing it will get hot and we will be pulling for about 5 hours? Or, do I pump them a little less, knowing they pressure will build with the heat....if so how much less? thanks everyone.

[Turtle_n_Peeps]

coolbreeze01 wrote:

Turtle n Peeps wrote:


Not really a new concept at all. It's simple, the more pressure you run the cooler the tire will run.

It's up to you whether you try it or not. When a tire maker recommends to run 10 over I will give it a try to keep my tires cool in hot weather to keep them alive. 35+ years, all with ST tires with one tire failure is a pretty good record I think.

You're turn OB.

Good info for those that didn't know. I've been lucky with ST tires too 😉

For some reason, the more I learn the luckier I get. 😉

[sh410]

Turtle n Peeps wrote:

Not really a new concept at all. It's simple, the more pressure you run the cooler the tire will run.

It's up to you whether you try it or not. When a tire maker recommends to run 10 over I will give it a try to keep my tires cool in hot weather to keep them alive. 35+ years, all with ST tires with one tire failure is a pretty good record I think.

You're turn OB.

It should be noted that ONLY Goodyear has endorsed that recommendation and ONLY for their Marathon tires. I don't think you can apply that to all brands of ST tires.

Further, ISTR tha one of the tire engineers was quoted on these forums that even though you can go over the Max PSI by ten, and go faster than 65 mph you must allow for decreased load. You can have increased speed OR increased load but not both.

[coolbreeze01]

Turtle n Peeps wrote:


Not really a new concept at all. It's simple, the more pressure you run the cooler the tire will run.

It's up to you whether you try it or not. When a tire maker recommends to run 10 over I will give it a try to keep my tires cool in hot weather to keep them alive. 35+ years, all with ST tires with one tire failure is a pretty good record I think.

You're turn OB.

Good info for those that didn't know. I've been lucky with ST tires too 😉

[TXiceman]

Do not over inflate tires. The tire manufacturers have a loading vs tire pressure chart. weight the truck and RV and set you re pressures off this when the tires are cold. Yes, they will warm up and the pressure will increase. Do not let pressure out during the day.

Ken

[Turtle_n_Peeps]

Old-Biscuit wrote:

Mine are 50 PSI and I run 60 PSI cold. Keeps the heat down when I tow in the 100 degree heat.

Now that's a new concept..........over inflate so they run cooler :H
Don't think I'll give that a try any time soon or ever.


OP
MAX PSI is MAX Pressure tires should be inflated to for max load rating.

If you check/adjust them in the morning...then 50# is what you should inflate to if 50# is your MAX PSI on tire.

Not really a new concept at all. It's simple, the more pressure you run the cooler the tire will run.

It's up to you whether you try it or not. When a tire maker recommends to run 10 over I will give it a try to keep my tires cool in hot weather to keep them alive. 35+ years, all with ST tires with one tire failure is a pretty good record I think.

You're turn OB.

[ktmrfs]

tire mfg state that tire pressure should be set when the tire is at ambient temp. then don't worry about temp rise during the day they are designed to accomidate the temp rise when running.

and most ST tire mfg state the tire should be inflated to the sidewall pressure regardless of tire load. this is different than your car/tv tire which has a tire pressure recomendation based on load and generally is lower than the max sidewall pressure.

[Drew_K]

That 50 psi rating is the cold rating before you start towing, so start the day at 50 psi. Also, you're better off with a too much pressure than too little.

[RCMAN46]

I have had a pressure Pro system on my trailer for 6 years.

I have noticed I can set the pressures in my shop building with an ambient about 65 degrees and no sun heating to worry about.

Then I start a trip early morning. I have found my pressures after 10 miles of towing will be within a couple pounds of the run early in the morning with ambient in the 50's vs the pressures late afternoon when the ambient is in the high 80's. This is always after towing 10 miles or so.

I have found ambient temperature and sun on the tires does not have as much effect on tire pressure as the friction the tires see after towing 10 miles.

[jadatis]

If 50 psi is the pressure needed for the maximum load and not the maximum pressure of tire , this 10 psi extra so 60 psi is allowed by the tire maker, and often adviced by them for ST tires even for 75m/h instead of standard 65m/h.

Only for normal car tires ( P-tires) and XL/Extraload/reinforced they give only maximum pressure on sidewall. From C-load/6PR ( maxloadpressure 50 psi) tires and up they give the maxloadpressure/ reference-pressure/ pressure needed for the maximum load on sidewall mostly like this "maximum load xxxx lbs AT yyy PSI( cold) " or in KG and kPa, and this is not the maximum ( cold) pressure of tire.
That maximum is probably ( as I concluded of PDF of Semperit( continental) 1.4 times the maxloadpressure// and then even cold.
when it gets warmer inside the tire this may even highen up .
I make that of the remark that a tire standing still ( so no heatening up of the inside air by driving or braking) is allowed to carry 2 times the maximum load when 1.4 times the maxloadpressure// .
Standing still only ambient temperature rising or sunshine can heaten up the tire inside. So I suspect the absolute highest pressure is about 1.5 to mayby even 2 times the maxloadpressure//.
Using 60 PSI instead of 50 is 1.2 times the maxloadpressure ( cold) so even enaugh is left for pressure rising bij temperature rising.
the tire can stand it and even the valves.

to make it complete maxloadpressure is for P-tires in American system always 35 psi regardles of what maximum pressure is given on sidewall.
for XL// its 41 psi. Extra between maxload- and maximum-pressure is used for highening up the maxloadpressure for higher speed then the speed the maximum load is calculated for .
This gives the tire lesser deflection and so lesser heatproduction by driving . Mind that the heatprocuction is what counts for giving damage or not to tire, and its a product of howmuch the rubber bends and bend back by every deflection and the times per second it happens when driving ( 50 m/h about 10 times a second ).

[Old-Biscuit]

Mine are 50 PSI and I run 60 PSI cold. Keeps the heat down when I tow in the 100 degree heat.

Now that's a new concept..........over inflate so they run cooler :H
Don't think I'll give that a try any time soon or ever.


OP
MAX PSI is MAX Pressure tires should be inflated to for max load rating.

If you check/adjust them in the morning...then 50# is what you should inflate to if 50# is your MAX PSI on tire.

[Turtle_n_Peeps]

Mine are 50 PSI and I run 60 PSI cold. Keeps the heat down when I tow in the 100 degree heat.

[poncho62]

Put 50 lbs in them...They are designed for the temp increase....Besides, lower pressure will cause more heat...and failure