Tow Vehicle Tire Pressure

[Ltynman]

Hi:
I have a 2014 Ford F-150 as my towing vehicle. The recommended tire pressure is 35 PSI. I tow a 6000 lb. (when fully loaded) trailer. I have a anti-sway/weight distribution hitch.
My question is, should I increase the tire pressure in my truck when towing?

Thanks for your response.

Norm

[Seachaser186]

Are you going by your door sticker or max psi on your tires?

[HONDAMAN174]

I would max out the rear to the sidewall number. As for the fronts, that will depend on how it feels to you. I have d rated and felt light so I run 45 and have more road feel.


2014 Evo 2850 "Woodstock"
2011 Toyota Tundra "Clifford"

[Ltynman]

Originally Posted by Seachaser186

Are you going by your door sticker or max psi on your tires?

The 35 psi is on the door sticker.

[Ltynman]

Maxing the rear tires makes sense to me. Sould help with the additional load and help them run cool.
Thanks for your thoughts on this.

[jadatis]

If you use a weightdistribution hich like you do , weight on rear tires is distributed partly, to tires of trailer and front tires of tow vehicle.
But you must keep the rear tires at pressure , so when WDH is put loose so more weight on rear, must yust be enaugh to get no damage to tires in that case. When WDH is working then you have some reserve and better fuel saving.

the 35 psi advice is pressure needed for maximum load up to 99m/h for Standard load P-tires,wich you most likely have, so is probably given as standard , and not calculated for the real loads on the tires, yust so the carmaker is in the clear with all the responcibilitys. Real needed pressure , I am able to calculate for you and is , because of the expected oversised tires you have , much lower, mayby even as low as 30 psi in rear.

So putting more then 35 in rear is to my expectation not needed, even not when towing without WDH working.
Check data on tires and try to determine the real weights on tires when towing, and give those here, and I will calculate.

[Seachaser186]

Back to my original question. Look at the Max PSI on the tires and add air accordingly when towing to control tire roll. Normally I run 36 PSI and inflate to 46 PSI for towing, makes a big difference. My Max PSI is 54, I am running 116T 18' P-tires.

[jadatis]

Strange maximum cold pressure of last poster.
54 psi , is that correct .

For P tires in standard load , mostly 44 psi to 50 psi is given as max cold pressure.
But this is not for P-tires the same as for LT tires, those give maxloadpressure/reference-pressure/will call it further AT-pressure on sidewall,and is the pressure needed for the maximum load up to max speed of tire, or if lower 160km/99m/h.

P tires in Standard load give only maximum allowed cold pressure , max allowed by the tiremaker, and AT-pressure is lower.
SL/standard load P-tire AT 35 psi
XL/reinforced/Extraload P-tire AT 41 psi

For the tires its not bad to put higher pressure in , but for comfort and gripp lower pressure , so more deflection of tire, is better.
So front tires of towing vehicle benefit from using lower pressure ( but not to low) for better gripp, assuming most cars have frontwheeldrive( but TS car probably rearwheeldrive, i realise now), but also braking is most on front wheels .

[Seachaser186]

Originally Posted by jadatis

Strange maximum cold pressure of last poster.
54 psi , is that correct .

For P tires in standard load , mostly 44 psi to 50 psi is given as max cold pressure.
But this is not for P-tires the same as for LT tires, those give maxloadpressure/reference-pressure/will call it further AT-pressure on sidewall,and is the pressure needed for the maximum load up to max speed of tire, or if lower 160km/99m/h.

P tires in Standard load give only maximum allowed cold pressure , max allowed by the tiremaker, and AT-pressure is lower.
SL/standard load P-tire AT 35 psi
XL/reinforced/Extraload P-tire AT 41 psi

For the tires its not bad to put higher pressure in , but for comfort and gripp lower pressure , so more deflection of tire, is better.
So front tires of towing vehicle benefit from using lower pressure ( but not to low) for better gripp, assuming most cars have frontwheeldrive( but TS car probably rearwheeldrive, i realise now), but also braking is most on front wheels .

Yes 116T tires have 54 psi and have more load rating than some LT tires.

[jadatis]

Can you give here exact sises so I can google?
116T must mean , maximum load 1250kg/2756 lbs and because you write its a P-tire , it must be those AT-pressure I gave.
T stands for maximum speed of 190km/about 118m/H
But then maximum load is given still for 35 or 41(xl) psi and up to 160km/99m/h, and for higher speed the pressure needs to be highened up with a system depending on speedcode.
But not important here because speed will stay far below 99m/h.
So I expect them to be pretty large tires to give that high maximum load.
The LT tires you say have lower loadindex, must be smaller then.
A 225/75R16 tire in C-tire ( EUR equivalent of LT) I found also in 116 loadindex but then with 65 psi AT-pressure, so yours must be mayby 18 inch and wider.

[Seachaser186]

They are 275/65R/18 116T

[Seachaser186]

Originally Posted by Seachaser186

They are 275/65R/18 116T

The load index is 2756; you would exceed GVWR way before the tire rating.

[Bama Rambler]

Now that we've sidetracked the OP's thread. I'm not sure they ever got a good answer.

Originally Posted by Ltynman

Hi: My question is, should I increase the tire pressure in my truck when towing?

Norm

I personally would increase the pressure to the max sidewall pressure when towing. It makes the sidewall a little stiffer and therefore helps with sway.

[wmtire]

Originally Posted by Seachaser186

and have more load rating than some LT tires.

If only the tire manufacturers would make it so easy.

There's a thing called "derating" when using a Passenger tire on a pickup or trailer. This thread may help explain that.

http://www.forestriverforums.com/for...ml#post1122253

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To the OP's question, it would help to air up your tires to the max stated on the tire when using the trailer. However, knowing if that is too much or not enough, is really dependent on how much weight is on the tires, which can only be properly ascertained by weighing it on scales.

[pdqparalegal1]

Originally Posted by Bama Rambler

Now that we've sidetracked the OP's thread. I'm not sure they ever got a good answer.



I personally would increase the pressure to the max sidewall pressure when towing. It makes the sidewall a little stiffer and therefore helps with sway.

Agree!! go with MAX sidewall recommended pressure less a litle in the fornt. Worst case is a hard ride but without a blown tire. All things being equal!

[Seachaser186]

Can somebody answer this question? If you inflate to max psi for towing the psi will increase when the tires heat up. Is the max psi for a cold tire?

[jftrombley]

Max pressure on the sidewall is cold. I towed a travel trailer with a Ford F150 and did raise the rear tire pressure to 50 PSI for my Bridgestone tires with a max of 55psi. If you have light truck tires that is what you do to prevent low pressure issue like rubbing the side wall.

[Seachaser186]

The reason I asked the question, there are those who are saying to inflate to max psi for towing. If you drive the psi will exceed the max. That is why I don't inflate to max to allow room for expansion.

[mnoland30]

The pressure rating on the tire is always specified cold. The tire company takes the expansion into account. I've often wondered when it is 120 degrees in Phoenix if they really took all of the expansion into account. The General Services Administration supplies the Forest Service with Passenger tires on all of the pickups it sells us. They don't hold up like Light Truck tires. I had two flats the same day multiple times. You'll find that LT tires are more stable and last better, but they definitely ride rougher.

[Chuckinca]

The door plate on my Ram 3500 states max rear tire pressure when loaded is 75 PSI and 45 PSI with light load.

What is the major advantage in running the rear tires at a much lower pressure?

.