Dually air pressure

[Bobplouhar0@gmail.com]

I have a 2018 Ram Dually what tire pressure should I run when loaded with my 16,000 lb mobile suites 17” wheels Nexon tires

[Cummins12V98]

First thing I would do is dump the NEXEN's that WILL have a tread separation.

Now the second thing is get your front end aligned to 1/64" toe. This WILL stop the outer front tire "STEPPING".

Third is proper rotation. Leave the rears alone! Fronts separate the tires from the rims leaving the rims at their current location and move the tires side to side with the rotation staying the same. This will put the outside of the tire to the inside. This will even out the tire from outer edge wear from turning.

Now the fourth is proper air pressure. The fronts ALWAYS leave them at 80psi. the rears when you are running around unloaded 30psi is more than enough. Loaded that is a question that cannot be answers properly without knowing what your actual weight is on the four rear tires. Fully loaded go to the CAT scales or any Highway scales. Now that you know your weights you can know your proper inflation.

Lookup the load/inflation chart for your tire size and load range. Add 5psi to the rear tire pressure on the chart. If you want to dial in the fronts do the same and add 10 psi, this will get you to 80 or darn close.

If you follow my recommendations that have been proven to get the best tire wear you will be a happy Camper!

Tires in pic have 40k with lots of tread left using the methods above. My truck 2015 RAM DRW weighs 16,000# fully loaded, with nearly 1/2 the miles towing.

I run 30 unloaded rear and 67 at full RAWR 9,750#

[dfrnt]

By 1/64” toe, you mean toe in, right?

[OneReallyOldGuy]

I just saw this thread. First off, how you can still have nexen’s on a 2018 is beyond me. Two of mine separated by 18,000 miles. Replaced all 6 with Michelins and I’m at 66,000 with lots of tread left.
I have to disagree with the tire rotation suggestion. I never reverse the direction of any tires. Manufacturer recommended 6 wheel rotation is, front to outside rear, outside rear to inside, inside rear to front. I bought from Discount Tire and they dismount all 6, rebalance and rotate at no charge every time I ask in any city I happen to be.
As far as tire pressure goes, I run what’s printed on the door placard. Front, 80psi COLD, rear, 65psi COLD, loaded or empty.

[Cummins12V98]

Originally Posted by dfrnt

By 1/64” toe, you mean toe in, right?

YES it does!

[Cummins12V98]

"I have to disagree with the tire rotation suggestion. I never reverse the direction of any tires."

Old Guy did you actually READ what I said about rotation?

Also if you are running empty for any length of time you sure could improve your ride comfort by lowering the rears to 30-35psi.

[Cummins12V98]

YES, NEXENS are pure junk!!! That is why I had them removed at 200 miles and sold on CL for $650 the first call. Replaced with Michelins. They only made it 40k and was given around $1,000 to buy any tires I wanted under their warranty. I went with Michelins again and now at 46k with lots of tread left.

[OneReallyOldGuy]

Originally Posted by Cummins12V98

"I have to disagree with the tire rotation suggestion. I never reverse the direction of any tires."

Old Guy did you actually READ what I said about rotation?

Also if you are running empty for any length of time you sure could improve your ride comfort by lowering the rears to 30-35psi.

I went back and reread your post and yea, I misread it. Sorry about that. I’m still not convinced driving around on severely under-inflated tires is a good idea. Anybody care to weigh in?

[4happyfeet]

Cummins12V98-how do you get your rear tires at 35 psi without the low pressure warning driving you crazy? Can that feature be disabled? I just bought a 2021 Ram 3500 with Nexens. I’m now concerned about them. What do I look for in regards to separation. Do they come apart like a blowout or get a bubble?

[Cummins12V98]

Originally Posted by OneReallyOldGuy

I went back and reread your post and yea, I misread it. Sorry about that. I’m still not convinced driving around on severely under-inflated tires is a good idea. Anybody care to weigh in?

They are NOT under inflated. There is a reason there is an inflation chart for every tire. At 35psi the lowest number I have MUCH more capacity than my actual weight.

Fact is with the proper inflation for the weight you have a better ride, better traction and better tire wear.

[Cummins12V98]

Originally Posted by 4happyfeet

Cummins12V98-how do you get your rear tires at 35 psi without the low pressure warning driving you crazy? Can that feature be disabled? I just bought a 2021 Ram 3500 with Nexens. I’m now concerned about them. What do I look for in regards to separation. Do they come apart like a blowout or get a bubble?

You don't have a TPMS you have a way to see tire pressure but ZERO warning with any 3500 RAM. Only 2500 RAM trucks give a warning.

NEXEN tires at around 25k +- have tread separation and possibly tread loss.

Go to Discount tire and get a set of their best Michelin or GY's and sell the NEXEN's on CL. Sold mine for $650 but I bet now with higher pricing they will net you at least $1,000.

[4happyfeet]

Sounds like a plan!

[Cummins12V98]

Originally Posted by 4happyfeet

Sounds like a plan!

Another small thing request they mount the balancing weights out of sight.

[CALinSC]

The correct inflation pressures have been published and displayed by the vehicle manufacturer. Why not just use them?

There is no provision in FMVSS to lower tire inflation pressures below vehicle manufacturers recommendations.

[Cummins12V98]

Originally Posted by CALinSC

The correct inflation pressures have been published and displayed by the vehicle manufacturer. Why not just use them?

There is no provision in FMVSS to lower tire inflation pressures below vehicle manufacturers recommendations.

ONLY inflation my truck lists is for FULL axle ratings. 80psi fronts and 65psi rears.

PLEASE explain if it's ok to run those pressures fully loaded why it's not ok to use the weight/inflation chart to lower the pressures for proper ride, traction and tread wear???

Use the charts and the brain GOD has given us.

"A RV trailer tire poster" Curious was this title self appointed or earned?

[CALinSC]

Originally Posted by Cummins12V98

ONLY inflation my truck lists is for FULL axle ratings. 80psi fronts and 65psi rears.

PLEASE explain if it's ok to run those pressures fully loaded why it's not ok to use the weight/inflation chart to lower the pressures for proper ride, traction and tread wear???

Use the charts and the brain GOD has given us.

"A RV trailer tire poster" Curious was this title self appointed or earned?

The regulations and tire industry agree that the recommended cold inflation pressures on the vehicle certification label are correct.

They describe underinflation as having a cold inflation pressure below what is recommended. They describe overinflation as having a cold inflation pressure above sidewall max. Everything in-between is optional.

The primary purpose for TRA load inflation charts is to SET recommended cold inflation pressures. Retailers rely on the load inflation charts to set inflation pressures for plus sized tires.

If a consumer is acting as a tire installer for OE tires, a load inflation chart is not needed as the correct inflation pressures are displayed on the vehicle certification label, tire & load placard and in the vehicle owner's manual.

Many consumers confuse FMVSS standards with FMCSA standards. They are not applicable with each other.

[Cummins12V98]

Can't use your own words to explain I guess or answer my question.

PLEASE tell my why every tire out there has a Weight/Inflation chart and you don't think it should be used.

I am guessing you work for some sort of Government Agency?

[CALinSC]

Originally Posted by Cummins12V98

Can't use your own words to explain I guess or answer my question.

PLEASE tell my why every tire out there has a Weight/Inflation chart and you don't think it should be used.

I am guessing you work for some sort of Government Agency?

Weight inflation charts were developed for the tire industry. They are standardized by the Tire and Rim Association (TRA). They are very useful for Original Equipment (OE) installers to speed-up production. They are not recommendations. They are precise inflation pressures divided in increments. They are necessary for aftermarket installers of plus sized tires and for determining inflation pressures when changing from “P” tires to “LT” tires.

They are probably most useful for consumers that increase a OE designated size to a higher load range.

It’s the industry misinformation that gets consumers confused. I cannot be wishy-washy with my tire presentations and that’s why I write strictly from industry regulations (NHTSA & FMVSS) and standards (USTMA).

Probably to get a better understanding of initial tire inflation pressures one should become familiar how and why the vehicle manufacturers determined and set OE tire inflation pressures. It’s quite simple, they MUST install OE tires that, at the vary minimum, provide – via inflation – a load capacity that will support the vehicle’s certified GAWRs. For automotive fitments GAWRs will provide the necessary vehicle load capacity reserves. For RV trailers there is no requirement for tire load capacity reserves. This is very important; vehicle manufacturers have the sole responsibility for setting OE tire recommended cold inflation pressures. Because the direction to do so is written in the FMVSS standards, those set inflation pressures become the minimum standard for that vehicle. Why? FMVSS standards are written to insure minimum standards are enforced by the manufacturing industry. It may be best understood when you read the basics for replacement tires: Replacement tires MUST provide a load capacity equal to or greater than what the OE tires provided.

The vast majority of RV trailer axles are overloaded on one end or the other. Only scaled weights can be used to manage the weight across their axles. As many have found, guessing at the proper weight for trailer tires can be very costly. At the minimum, follow the vehicle manufacturer’s minimums.

A lengthy post getting longer: the following quote is from the USTMA RV tire instruction manual. It encompasses both Motorized RVs and RV trailers.

“Inflation pressure recommendations may also be determined based on the tire manufacturer’s specifications, which define the amount of inflation pressure necessary to carry a given load. These inflation pressures may differ from those found on the vehicle tire placard or certification label. However, never use inflation pressures lower than specified by the vehicle tire placard, certification label or owner’s manual. Nor should inflation pressure exceed the maximum pressure molded on the tire sidewall.”

[Cummins12V98]

Incredible!!!

[Notanlines]

Actually he DID work for ‘some sort of government agency: ‘. The US Air Force for many years. And thank you to Cal for that!