Tire pressure — should I bump up the pressure on my truck's tires?

[WhereStream]

I know a lot's been said about tire pressure on the trailer, but ... what about tire pressure on the tow vehicle?

Should I kick up the tire pressure on the truck (or, in my case, SUV) when towing?

I remember adding extra pounds of pressure when towing was taught way back in the bias-ply days (I recall watching a PSA about tire pressure on our black-and-white TV).

Nowadays, though, I've not heard a thing about it, and the wwner's manual doesn't address this question.

[out of sight]

I keep my trailer and rear truck tire pressures at maximum, as recommended by the manufacturers. That's 80 PSI for both the Airstream and truck. High pressure increases towing stability by increasing the sidewall stiffness. I also keep a healthy load on the tow vehicle's rear axle as this also increases sidewall stiffness. Some people use lower pressures because they are worried about the ride but it's safer to have high pressures.

If you have a newer tow vehicle then it probably has a tire pressure monitoring system (TPMS). You also need a TPMS for the Airstream tires. If you get a flat or blowout you will not feel it until the tire disintegrates. If that happens you will wipe out your wheel well at a cost of $1000 to repair.

[thewarden]

Bill, there are a couple of schools of thought when it comes to determining proper tire pressure. The first is to check the tire pressure sticker on the drivers door jam and inflate to the stickers recommended max pressure whenever you are loaded or towing.

The second is to check the inflation table for your specific tire and inflate to the recommended pressure based on whatever your load is. You can find that on any tire manufacturers website. In this case you will need to know how much weight is on each of your axles in order to set proper pressures, so a trip to the scale would be in order.

When in doubt, I would always inflate to the maximum pressure indicated on the door sticker when towing. The vehicle manufacturer will have set that pressure to ensure proper handling and braking in an emergency maneuver.

[ghaynes755]

Warden the tire pressure on the door sticker is usually the max pressure for the tires installed. I don't think the manufactures put something lower on the sticker than what is the speced by the manufacturer.

[dznf0g]

Originally Posted by ghaynes755

Warden the tire pressure on the door sticker is usually the max pressure for the tires installed. I don't think the manufactures put something lower on the sticker than what is the speced by the manufacturer.

This is the correct answer....at least for GM vehicles. I quizzed the Brand Quality and engineering folks a number of years ago. Door placard pressure is the spec for full axle loads. If you're overloading axle(s) above spec, you should bump up Pressure. Warning: you may likely be creating other problems!! The real question is, when your not loaded (ie. empty truck or SUV, should you lower pressure for ride quality. I couldn't get the engineers to commit....they hem/hawed around and said to inflate to placard pressure and forget it. I do lower the pressure in the rears of my Silverado by just a few pounds when empty. Stops that irritating hop over rough pavement.

[drbrick]

For the TV the sticker on the door is there to ensure you run with the correct tire pressure. For your AS the tire manufacturer tire pressure guide is load specific.

For example: On my F-150 with BFG KO2 20" I run 38# on my AS 25 Int'l CCD (6400#) with GYE 15" I run 67# both are the manufacturer's recomendation. IMHO they should know better than I what is best

[gypsydad]

Everyone here is an "expert", right? Follow your tire manufacture recommended PSI for the load/use model is my motto.

Goodyear Endurance has a recommended PSI for your particular application...for my 28' AS after weighing, it is 50-55PSI cold; running them at "Max Pressure 70PSI" when cold, caused rivets to pop, doors to open, and hinges to break; need I say more?? Goodyear says following the recommended tire pressures will not cause any excess wear...now, who you going to believe...the "experts" here who say "I run my tires at max pressure.." or the mfg??. It's your trailer....

For my F250 TV, I run the 275/65/20" Michelin AT's at 75PSI when pulling my AS; 80PSI is max. Be safe!

[TUDO BEM]

I recently purchased (June 2019) a new F-150 with Max tow Pkg and all the bells and whistles. I have 12000 miles on it now with 9000 miles towing my 2009 27FB Classic Airstream. (I previously pulled this trailer with a 2008 F250 Diesel for 135,000 miles). I used the Door Placard recommendation of 35PSI on the 275/55R 20 A/T Owl 113T tires that came with the F-150. While traveling I noticed in high wind conditions that I had some handling issues. Most of my travels were in the Rockies with high pass driving (Up to 11800ft). When I returned I checked with the local Ford Dealer (got no help) about the correct pressure of my truck tires when towing. They recommended I check with Discount Tire. So I did and this is what Discount Tire said after they researched their resources. I should use 5-6 lbs more (ie 40-41psi) when I am towing my Airstream. By the way 51psi is the max pressure on my f150 tires.

[mpsgolf]

Tire pressure recommendations by manufacturers are load dependent. The sidewalls say “xxxx lbs at max pressure xx psi.” I don't run max all the time - no sense jarring your fillings loose when you dont need to. I do go above “normal daily” on TV when I tow due to additional weight on the vehicle. My $.02.

[thewarden]

Originally Posted by ghaynes755

Warden the tire pressure on the door sticker is usually the max pressure for the tires installed. I don't think the manufactures put something lower on the sticker than what is the speced by the manufacturer.

That is correct, mostly. I have a 1 ton SWD GMC. The door sticker indicates the recommended pressure for the front tires is 65 psi. The max pressure from the tire manufacturer is 80 psi.

That is why I indicated that the other method of determining proper pressure is by load weight, which, depending on your load, may allow you to lower the pressure from the sticker pressure for ride comfort, etc.

I also said, if in doubt, inflate to the stickers max as you will always be safe in doing so. This certainly does not take into account "best ride", rather "safest ride". Best ride will involve knowing your loaded weight and inflating to the tire manufacturers recommended pressure using their load table to find the correct pressure for the weight you are hauling, being sure to add a safety margin.

[franklyfrank]

Originally Posted by thewarden

That is correct, mostly. I have a 1 ton SWD GMC. The door sticker indicates the recommended pressure for the front tires is 65 psi. The max pressure from the tire manufacturer is 80 psi.

That is why I indicated that the other method of determining proper pressure is by load weight, which, depending on your load, may allow you to lower the pressure from the sticker pressure for ride comfort, etc.

I also said, if in doubt, inflate to the stickers max as you will always be safe in doing so. This certainly does not take into account "best ride", rather "safest ride". Best ride will involve knowing your loaded weight and inflating to the tire manufacturers recommended pressure using their load table to find the correct pressure for the weight you are hauling, being sure to add a safety margin.

On my 2017 F-250 Powerstroke door specs by the manufacturer recommends 60 PSI in front tires and 75 PSI on the rear tires.
Front axle weight without load is @ 4,200 lbs the rear is half of that which makes sense because the payload on the truck is 2,320 lbs.
That pretty much tells me that it is safe to run the rear tires at 60 PSI as well without load which I do, it improves the empty ride tremendously. Obviously I do increase the rear tire pressure when I load the truck.
I also adjust the Trailer tire pressure for the load which results in a much better ride. It is a fact that trailer bounces around a lot more at 80 PSI than at 72. I run Michelin 16" LT E rated tires on the trailer.
You couldn't do this with ST tires however.
I increase the pressure to 82 PSI when the trailer is parked at the house for extended periods.

[uncle_bob]

Hi

If you want to read up on more than you would ever want to know, go back a few years and take a look at the Ford / Firestone debate over tire pressure on the Expedition. More or less, Ford wanted you to run lower pressure to improve the ride. Firestone felt this was not correct in all cases. It got pretty crazy and ultimately Firestone went from being the preferred tire supplier to Ford (since the days of Henry Ford) to "off the list".

If you run "to much" pressure in the tires for the load you are at, they will be just a bit high in the center. That will increase wear and shorten the life of the tires a bit. The same "middle high" situation will decrease traction a bit. Indeed in loose sand, you likely want to let air out of your tires (like a lot of air).

If you run "to little" pressure, the tires flex more. That may get them hotter than they like to be. It also is going to increase wear on the sidewalls. As noted in other posts, it probably makes them a bit more flexible.

You can indeed find websites and YouTube videos talking about weighing the load on each tire individually each day. You then adjust the truck and trailer tires that morning before you set off. I would suggest that these people being in the business of selling weighing equipment just *might* be a factor in those "suggestions"

How much use do you put on your trailer tires? Do you wear out the tread from running down the road? Some of these tires have a 50 to 60,000 mile rating on them. Do you go that far with the trailer in 5 to 10 years? (we do). If not, they likely will rot out before you get into highway wear related tread issues.

Lots of variables.

Bob

[Daquenzer]

My F150 tires say 38psi. I run at about 40psi (cold) while towing. Not really sure it makes much of any difference except in my head. I do know the last time out I felt the back end was a little sloppy. I checked the tire pressure and one tire was at 32psi. We turned around and went to a station we just passed and I inflated it to 40psi. Thankfully there was no air leak. But clearly the handling improved.

I don't think you will hurt anything by adding a bit of extra air over the recommended PSI I would experiment with your vehicle.

As to the AS I keep mine at 80psi cold which is what the sticker says for max psi. I haven't had popped rivets (yet). And the tires seem to be wearing quite evenly. My feeling is that if I start adjusting PSI based upon load it's just one more complication to deal with. I like the KISS principle.

[guskmg]

When you think about it correct tire pressure causes even tread wear if the inflation is correct for the load. That is: if the pressure is low or the load is excessive you will get more wear on the outside edges of the tires. Conversely, if the pressure is too high or the load is to light the center of the tires will wear. Therefore, after a few thousand miles carefully look at (measure) tire wear and determine which is the case. Over or under inflated, adjust accordingly. In my case with all 10 Michelins tires at 80 psi max and no uneven wear after thousands of miles I have determined that the tires are running at near maximun load at max tire placard pressure. Don't forget to rotate and keep the pressure at the correct loaded amount. TPS monitors are great inventions for tire safety.
guskmg

[davidz71]

E rated tires on 2500hd truck are set 70 lbs rear and 58 on front.
D rated tires on '86 25' Sovereign are 60 lbs.

80 lbs. on truck and 65 lbs. on trailer would be tougher than I'd like on my trailer.

[out of sight]

It's not about getting a smooth ride or tire wear. It's about towing stability, which is highly dependent on tire sidewall stiffness. Inflating to the maximum will make your tow safer.

I have never had a popped rivet despite that I keep my tires at 80 psi.

[Ronyx]

Originally Posted by out of sight

It's not about getting a smooth ride or tire wear. It's about towing stability, which is highly dependent on tire sidewall stiffness. Inflating to the maximum will make your tow safer.

I have never had a popped rivet despite that I keep my tires at 80 psi.

Maximum pressure is just that, the maximum pressure the tire is designed to accommodate. It does not mean "this is the recommended operating pressure for all loads and conditions". Inflation pressures not properly matched to load can impact the safety of the tire from a wear, traction, handling and braking perspective. Doing a net search of "proper tire inflation" yields many results supporting this.

[davidz71]

Originally Posted by out of sight

It's not about getting a smooth ride or tire wear. It's about towing stability, which is highly dependent on tire sidewall stiffness. Inflating to the maximum will make your tow safer.

I have never had a popped rivet despite that I keep my tires at 80 psi.

That is just it, my stability is right on with rear truck tires no less than 70 lbs. When I go below that I can feel the truck start to squirm. Higher than 70 lbs. and I notice no increase in stability but why go higher with my combination if it isn't needed. Each to their own and I know what works for me.

[out of sight]

There is no net search that will tell you that deflating your tires is going to make your rig more stable.

[WhereStream]

The tire placard on my new Expedition says to run the rubber at 39 pounds, fore and aft.

These are 20-inch, low-profile tires, which I'm not familiar with.

The low-profile should be good for towing — sidewall less likely to wiggle.

But low profile means low volume of air, so I'm wondering if that means I should do anything special when there's an extra load on the axles.