Tow Vehicle front tire air pressure question

[Ephraim]

We tow a 2019 Classic 30RBQ with a 2006 Dodge Ram 2500 2WD.

The name plate says to run the tires at 40 front/50 rear when unloaded and 50/0. when loaded.

We've been doing that and it has been handling just fine. However, I've noticed that the scales are reporting the same axle load whether loaded or unloaded. That manual states that it is not necessary to restore all of the weight back onto the front axle when loaded. Here are the numbers from the last trip. Note that without the WDH, the steer axle is about 200lbs lighter than this.

Unloaded:
Steer: 3600
Drive 4280

Loaded:
Steer: 3540
Drive: 5220
Trailer: 8940

Is it really necessary to run the front tires at the higher psi when the weight on them doesn't change much between hitched and unhitched?

[Bcc75]

Great question.
I’ve often wondered about that. I have an F250 and honestly I don’t adjust mine loaded or unloaded. I keep all 4 consistent while unloaded according to what the door sticker says and don’t adjust when loaded. Works fine for me. I do run the trailer tires at 63-65 though. Helps soften the trailer ride and Keeps things from bouncing around so much

[Bill M.]

I wonder about that with my 2500 too. I run about the same in the front loaded or unloaded. Maybe a little more air would make it more stable with the tow. I do adjust the rear down after towing season is over.

[wulfraat]

Tires should be inflated based on load.

Too much pressure and you compromise handling and traction.

Too little and you get excess heat buildup / all sorts of other fun issues.

[ROBERTSUNRUS]

Hi, my F-150 came with load range "C" LT tires from the factory. My door sticker says to run 40 lbs. in all of the tires. These tires have a max pressure of 50 lbs. I leave my front tires at 40 lbs. but set my rear tires at the max pressure of 50 lbs. At 40 lbs. or 45 lbs. in the rear tires, I felt a little push on turns, so I upped my rear tire pressure to the max of 50 lbs. and it handles great.

[Ephraim]

Originally Posted by wulfraat

Tires should be inflated based on load.

Too much pressure and you compromise handling and traction.

Too little and you get excess heat buildup / all sorts of other fun issues.

Not to mention the bone jarring ride with overpressure. The 70 psi of the rear is required when hitched as I am right at the weight limit of the tire then. I do drop it to 50 when not hitched because I'm likely to not have any teeth left if I don't. The truck is heavier than the sticker. I think a truck normally has more weight on the front than the rear when unloaded, but I'm running a heavy fiberglass topper with Decked drawers and tools so "unloaded" is a relative term.

[Profxd]

Front to rear tire pressure differential effects how the vehicle handles, it’s not just about by load. It changes how the vehicle reacts to steering input.

[mykytiukr]

Originally Posted by wulfraat

Tires should be inflated based on load.

Too much pressure and you compromise handling and traction.

Too little and you get excess heat buildup / all sorts of other fun issues.

The short answer to the original question is….No.

[NeahBay]

I bought my 2018 F150 used. The dealer, or previous owner, swapped the original Michelin tires (43 lb max pressure), for Hankook (53 lb max). The door sticker references the Michelin pressure. My point: check the load and proper COLD air pressure rating on the side of the tires, and compare those figures with the door sticker.

Bob

[superChop]

Not sure what others are experiencing, but our E rated tires are filled to 70 PSI of 80 max. Why lower than max? Long Long Honeymoon YouTube channel recommended AND with our TPMS in our ‘19 F250 shows 80 PSI (70PSI COLD/80PSI hot) for most of our current cross country trip. Recommendation is to allow for increased pressures on hot summer days.

[jaybauman]

Originally Posted by superChop

Recommendation is to allow for increased pressures on hot summer days.

This is certainly a really bad recommendation. You fill your tires to your desired/required pressure when the tires are cold, i.e. the vehicle has not been driven. Tires and designed and engineered for the increased temperatures and pressures during operation.

[Mikebrady62]

[QUOTE=Ephraim;2508972]We tow a 2019 Classic 30RBQ with a 2006 Dodge Ram 2500 2WD.

The name plate says to run the tires at 40 front/50 rear when unloaded and 50/0. when loaded.

We've been doing that and it has been handling just fine. However, I've noticed that the scales are reporting the same axle load whether loaded or unloaded. That manual states that it is not necessary to restore all of the weight back onto the front axle when loaded. Here are the numbers from the last trip. Note that without the WDH, the steer axle is about 200lbs lighter than this.

If you do not notice a rougher or loose feeling when you are driving, more pressure (not exceeding max) is going to give you longer tire life and create less drag. I reduce my pressure when not towing to give me a smoother ride. Increase when towing for more stability in the rear.

[RivetED]

Originally Posted by Profxd

Front to rear tire pressure differential effects how the vehicle handles, it’s not just about by load. It changes how the vehicle reacts to steering input.

____________________
Warning Message
Caution! Most advice given here is nothing more than a subjective opinion. Please reference the vehicles owner manual for instruction on towing and hitch use which is based on physics, facts, and research.


...Profxd makes an excellent point and a warning that is spot on. That's only my opinion.

[jcanavera]

My 3/4 GMC passenger van sticker shows that loads really only require pressure changes on the rear tires. I'm using 225x75 R16 E rated tires. Front tires show an inflation pressure of 55 psi, regardless of weight. Rear tires show 80 psi under full load. Typically I'll run the rears at about 65-70 psi when I'm unloaded or not towing. 80 psi in those rears with no load is pretty noticeable on ride quality.

Jack

[jadatis]

Fully loaded is something else then when towing.
And even then front not much more weight then only driver in car.

And neded pressure is all about weight and speed.
Wonder why only 60 lbs less on front, is it a 5thwh or are you using WDH verry tight on the chains?

Speed is probably lower when towing.
Car-advice is often given for max technical carspeed ( higher speed needs higher pressure .

So no in your case same pressure front can do fine, only rear needs higher.

[Dick tracy]

recommended PSI when not towing or loaded is 36psi. when towing I run 45 front and 65 rear.
when not towing and running these pressures, the rear really "hooks up" more noticeably, faster throttle response, almost jumps when I nail it. much stiffer when not towing. temperature is the key element.

[avonroemer]

I would recommend getting the tire chart for your specific tire from the manufacturer, which will provide the load rating for each tire at various pressures. Then take your vehicle to a CAT scale and weigh without the trailer and then with the trailer loaded for a typical trip. The tire chart will show what pressure is required for your loads, both unloaded and loaded.
Then, I would verify those settings using the chalk test. On a level surface, put a strip of chalk about an inch wide across all tires on the tread, then drive forward 100 feet and look at the chalk strip. If it has worn evenly then you have the correct pressure, if worn off at the center you are too high, if worn at the edges then too low. It may take a few passes, but you should be able to come to a correct pressure for you loads and within the tire pressure chart.

[tjdonahoe]

My 17 ram 4x4 says 60 front. 80 rear….lol why…my loaded weight is equal…so I runs 70 lbs of air front and rear….loaded and empty

[A W Warn]

Originally Posted by Ephraim

We tow a 2019 Classic 30RBQ with a 2006 Dodge Ram 2500 2WD.

The name plate says to run the tires at 40 front/50 rear when unloaded and 50/0. when loaded.

We've been doing that and it has been handling just fine. However, I've noticed that the scales are reporting the same axle load whether loaded or unloaded. That manual states that it is not necessary to restore all of the weight back onto the front axle when loaded. Here are the numbers from the last trip. Note that without the WDH, the steer axle is about 200lbs lighter than this.

Unloaded:
Steer: 3600
Drive 4280

Loaded:
Steer: 3540
Drive: 5220
Trailer: 8940

Is it really necessary to run the front tires at the higher psi when the weight on them doesn't change much between hitched and unhitched?

Originally Posted by Ephraim

Not to mention the bone jarring ride with overpressure. The 70 psi of the rear is required when hitched as I am right at the weight limit of the tire then. I do drop it to 50 when not hitched because I'm likely to not have any teeth left if I don't. The truck is heavier than the sticker. I think a truck normally has more weight on the front than the rear when unloaded, but I'm running a heavy fiberglass topper with Decked drawers and tools so "unloaded" is a relative term.

My $.02>
In my opinion you are not getting the full benefit of your weight distribution system. I think you would be better off, ride comfort and tire load, if you would tension the hitch just a bit more, so that it restores or adds a bit of weight to the front axle and shifts a bit off of the drive axle onto the trailer axles.
The manual may say that it is not necessary to shift this weight, but it does not say don't do it.

[2008AS]

Originally Posted by ROBERTSUNRUS

Hi, my F-150 came with load range "C" LT tires from the factory. My door sticker says to run 40 lbs. in all of the tires. These tires have a max pressure of 50 lbs. I leave my front tires at 40 lbs. but set my rear tires at the max pressure of 50 lbs. At 40 lbs. or 45 lbs. in the rear tires, I felt a little push on turns, so I upped my rear tire pressure to the max of 50 lbs. and it handles great.

I think we have the same set up. . Goodyear Wrangler 18” LT’s?

I have played with tire pressure and most recently settled on 42 front and 45 rear. I have also run at 50 , 50. I still get that push pull feel even after cranking down on the sway bars.

My only hope to solve this loose feeling is to replace the tires with heavier duty truck tires. I’ve never wanted a set of tires to wear out so fast in all my life of vehicle ownership.