Air pressure in dually rears....

[Raptor Dave]

What is a good pressure to run in them fully loaded at around 17K on a toy hauler.
I'm getting answers from 65 to 80.
May as well get some more answers.

[Badbart56]

I run 65 in mine empty or loaded. Have had no issues.

[xrated]

Originally Posted by Raptor Dave

What is a good pressure to run in them fully loaded at around 17K on a toy hauler.
I'm getting answers from 65 to 80.
May as well get some more answers.

Run whatever the sticker on the door post states, as long as the tires are either OEM tires OR they are the same size and load capacity rating as the OEM tires. Inflating to that number on the door post, will give you enough tire load capacity to take your truck all the way to the GVWR, and beyond...it you do the math. If you overload the truck beyond that, or have tires that don't have enough load capacity, then you're on your own.

My Dually states 65 psi on the door sticker and I never run them more than that....even when the truck, as scaled on a CAT scale, was at 13,800 lbs....just shy of the 14K GVWR

[jsb5717]

Ditto, I run mine at 65 psi per the door sticker as well. I would imagine you could run them up to the tires max limit if you wanted. But that might only serve to stiffen the ride without added benefit.

[xrated]

Originally Posted by jsb5717

Ditto, I run mine at 65 psi per the door sticker as well. I would imagine you could run them up to the tires max limit if you wanted. But that might only serve to stiffen the ride without added benefit.

It would definitely stiffen the ride, and it would add some tire load capacity for each tire....BUT....there is no reason to do that as the door post psi inflation number will give you more than enough capacity to overload your truck past the GVWR of the truck........which of course should not be done.

[notanlines]

Dave, you’ll get the same answer here. 70 on the rear with the Continentals, towing 22k. Just passed 80,000 and they look good.

[gearhead]

Per door sticker..65 when loaded.
The Landmark is 18,000GVW and the Bigfoot will weigh 4500 loaded.
If I know I will be unloaded for awhile I’ll drop them down to 45 or 50.

[Badbart56]

If you run them higher than 65 PSI (per the door sticker) you'll get a rougher ride when you're empty or lightly loaded, but you'll also wear out the center of the tires over time.

My Fusion 405 has been loaded to 18,000 in the past and the rear tires on my dually showed no sign of being overloaded at 65 PSI. I have run sustained 70-75 mph on the interstate with 5240 pounds on the front axle, 7480 pounds on the rear axle, and 13,300 pounds on the three trailer axles (per the CAT scale ticket) and I've had no failures.

[vampress_me]

I’m also a part of the “door sticker says 65 psi”, and that’s what i run them at. OEM tires lasted to 59,000 miles doing that, and truck was happy the whole time. So, I figure I’ll keep going based off the door sticker.

[JDDilly]

I run at what is posted inside the door.

[rhagfo]

The rear axle on our 2016 Ram 3500 DRW is rated at GAWR of 9,750# at 65 psi. I don’t think it needs to be any higher than 65 psi.

[ACJCF2]

65 psi dual.

[Tireman9]

Originally Posted by Raptor Dave

What is a good pressure to run in them fully loaded at around 17K on a toy hauler.
I'm getting answers from 65 to 80.
May as well get some more answers.

"Duals" means 2 tires, side by side on each end of an axle as with many 1-ton Pick-ups
"Tandem" means two axles with one tire on each end of each axle of a tow-able



To me a "Toy-hauler" is usually a pull along trailer or 5th wheel trailer but there are some "Toy-Hauler" Motor-homes built on truck chassis with Dual tires on the drive axle.



For a trailer application there is a Certification Label on the Driver side, outside toward the front of the trailer. That label, per Federal Regulation and RVIA guidelines states the GAWR (max load on each axle), Tire Size, Tire Load Range (C, D, E) and the minimum cold inflation required by the tires to support the GAWR. If 2018 or newer the MINIMUM inflation is 110% of what is found in tire load & Inflation tables published by the tire industry.


It is best if you know your actual load for each tire position or at least for each individual axle as the actual load is almost NEVER evenly split between the tires. If you can only get the load on each axle use the weight of the heavier axle and assume that one end of that axle has 51% to 52% of the total weight of the axle. Using the calculated load consult the published Load & Inflation tables such as found here
https://www.goodyearrvtires.com/pdfs/rv_inflation.pdf
NOTE all the other tire companies have similar charts with THE SAME inflation numbers so you can use the GY table.


I recommend that you set your minimum COLD inflation to 110% of the PSI found in the table for your loading. I also recommend that your TPMS Low Pressure Warning be set to 105% of the PSI found in the table. Your High Pressure warning can be 120 to 125% of your COLD inflation number and your High Temperature is good at 158°F.


You will find many other folks offering info on what they use on their RV but I would bet against them having identical load on their tires. I am an actual Tire Design Engineer with 50 years experience in tire design and failed tire forensics. or you can ignore my recommendations and go with whatever Bubba suggests. Your choice.

[lunge motorsport]

FWIW
In my vehicles I set tire pressure based on the temperature across the tread. For the tow vehicle, I load the vehicle to typical weight when towing and then run down the highway for approx. 30 minutes to bring the tires to operating temp. I then measure and note the temps in 3 different areas across each tire, inside, middle, and outside. This must be done quickly as the temps tend to "blend" together the longer the delay after stopping. The goal is to equalize temps as closely as possible. I have never seen equal average tire temps on every location. My main takeaway from this exercise is that in all cases, on every dually I have owned, I found that the inner rear tires on the dually wants to see about 5-8 psi greater pressure than the outers. This is empty or loaded.
I'm interested in the tire engineers opinion/input in this regard.

Cheers

[Tireman9]

Originally Posted by lunge motorsport

FWIW
In my vehicles I set tire pressure based on the temperature across the tread. For the tow vehicle, I load the vehicle to typical weight when towing and then run down the highway for approx. 30 minutes to bring the tires to operating temp. I then measure and note the temps in 3 different areas across each tire, inside, middle, and outside. This must be done quickly as the temps tend to "blend" together the longer the delay after stopping. The goal is to equalize temps as closely as possible. I have never seen equal average tire temps on every location. My main takeaway from this exercise is that in all cases, on every dually I have owned, I found that the inner rear tires on the dually wants to see about 5-8 psi greater pressure than the outers. This is empty or loaded.
I'm interested in the tire engineers opinion/input in this regard.

Cheers

Unless you are measuring tread temperature with a needle probe at the belt edges, taken within the 1st 10 to 20 seconds of stopping I would not trust your numbers. This is based on my work with some drivers named Andretti, Ruby and Unser at a little track in Indiana. Tread surface temperature is not the critical location.

[notanlines]

I can only imagine as anal as some members are with this 3 to 5 psi and 5 to 10 degrees tread temperatures what they might be like with beer temperatures, grill temperatures, miles per gallon and trans fats in their margarine rather than real butter, when in hell do y’all actually start having fun on a camping trip?
Dear God, set the tires at 65 and get on down the road!

[sourdough]

Originally Posted by notanlines

I can only imagine as anal as some members are with this 3 to 5 psi and 5 to 10 degrees tread temperatures what they might be like with beer temperatures, grill temperatures, miles per gallon and trans fats in their margarine rather than real butter, when in hell do y’all actually start having fun on a camping trip?
Dear God, set the tires at 65 and get on down the road!

Jim, Jim! Trans fats? Margarine? Didn't they outlaw all that stuff when the CDC said we should all consume 1 lb. butter per day (seems I recall that)? I'm loving it. MPG? It is what it is. I don't have any idea other than what the pump says I owe... I'm going to go...it's going to cost...I'm not stopping in the middle of a trip or cancelling one because fuel went up a dime....

Thanks. For a moment I was thinking about delaying our next trip because quik stop water was going to cost more.....

[flybouy]

Originally Posted by notanlines

I can only imagine as anal as some members are with this 3 to 5 psi and 5 to 10 degrees tread temperatures what they might be like with beer temperatures, grill temperatures, miles per gallon and trans fats in their margarine rather than real butter, when in hell do y’all actually start having fun on a camping trip?
Dear God, set the tires at 65 and get on down the road!

Don't forget to stop every hundred miles or so to restore max aerodynamics. You have to wash the and wax the truck and rig to remove bugs & dirt to enable smooth airflow!

[rhagfo]

Originally Posted by Raptor Dave

What is a good pressure to run in them fully loaded at around 17K on a toy hauler.
I'm getting answers from 65 to 80.
May as well get some more answers.

Well without TV information year and axle weight rating a little hard to give a solid answer. That said, our 2016 Ram DRW, we have a rear GAWR of 9,750# and a truck GVWR of 14,000# and payload of 5,411#. If one deducts the total payload from the rear axle rating leaves 4,339# about what my rear axle weighs ready to tow. The 65 psi is for the axle 9,750# rating, so 65 psi should e plenty.