Max PSI towing

[martinto]

New 2016 Sierra 6.2L 4X4 with max tow pkg. Goodyear P275/55R20's rated at 44 PSI Max. Towing TT dry at 5800 Lbs loaded between 6500 - 7000lbs. Heading cross country to the PNW in mid August. would like to hear perspectives on PSI. in my previous Yukon Denali i would go to 40PSI cold all around for towing. Thinking that would be sufficient to firm up the sidewalls on my Sierra as well. Last week in 90-100 degree temps, my cold 40 psi fill went up to 43 psi when running. Some have suggested i go 44 MAX on rears and 36 on fronts. Whats the experienced views on this forum?

[SeaDog]

Your truck tires are designed to carry max load at a specific psi which can be found on the sidewall of the tire. there may be 2 figures there one for dual and one single. I would follow what the tire says

[wyo700]

When towing yes at only 44 psi max out the tires front and rear it's not going to hurt anything.

[Riccochet]

Usually the max load is at max PSI. Just run them all at max PSI cold and be done with it.

[Kenny kustom]

I would swap out the passenger tires for a set of truck tires.


2016 Sabre 36QBOK
2015 Ram 3500 CUMMINS

[Airdale]

Originally Posted by SeaDog

Your truck tires are designed to carry max load at a specific psi which can be found on the sidewall of the tire. there may be 2 figures there one for dual and one single. I would follow what the tire says

That's not true for trucks with original equipment Passenger tires. The vehicle manufacturer was required to de-rate them. Take the maximum load capacity molded into the "P" tires sidewall and divide it by 1.1, the result is than the maximum load capacity for service on your truck.

[Airdale]

Originally Posted by martinto

New 2016 Sierra 6.2L 4X4 with max tow pkg. Goodyear P275/55R20's rated at 44 PSI Max. Towing TT dry at 5800 Lbs loaded between 6500 - 7000lbs. Heading cross country to the PNW in mid August. would like to hear perspectives on PSI. in my previous Yukon Denali i would go to 40PSI cold all around for towing. Thinking that would be sufficient to firm up the sidewalls on my Sierra as well. Last week in 90-100 degree temps, my cold 40 psi fill went up to 43 psi when running. Some have suggested i go 44 MAX on rears and 36 on fronts. Whats the experienced views on this forum?

Normally the inflation pressures found on the tire placard (certification label) are appropriate all the way to the vehicle's GVWR. If they are not, the vehicle owner's manual will have the recommended pressures for towing conditions.

[chriscowles]

I tow a Shamrock 21DK hybrid with a 2005 Dodge Durango. I swapped out the Durango OEM P tires for LTs. When not towing and with the truck tires inflated as listed on the door frame for P tires, there is little difference in handling.

If inflated to full capacity as was done as a "courtesy" at a local dealer the LTs are like rocks and handling is terrible when under tow. I deflated them down to 50 front/60 rear with significant improvement.

The tire manufacturer (Michelin) publishes an inflation guide with recommended pressures for given payloads. For the load ranges I generally carry when towing, their recommendations are far less than the capacity printed on the tire.

Consider getting LT tires and following the tire manufacturer's pressure recommendations for the specific load you're carrying.

[Airdale]

Some tire manufacturers have web pages in PDF format on the internet explaining the correct procedures for setting recommended tire pressures for replacements. Toyo and Firestone are the best ones. Both follow industry standards, as do all others.

The lead-off in such instructions are very much the same. Tire manufacturers DO NOT set tire pressures for vehicles that were built under FMFSS regulations, the vehicle manufacturers do. The vehicle manufacturer sets the standard for a vehicle with the Original Equipment (OE) tires. Here is a short version of how it works when changing designs from Passenger (P) to Light Truck (LT) tires.

The new tires must be capable of providing the load capacity the OE tires provided. When changing from P to LT tires one must understand that the vehicle manufacturer was required by FMVSS regulation to de-rate the P tires on any truck. So, when you use the load & inflation chart for the P tires to determine what the load capacity is set at, via the vehicle manufactures recommended pressures, you must divide the number by 1.1 to get the actual and official load capacity provided. Then you can take that value to the load & inflation chart for the LT tires.

Once the new recommended inflation pressures are determined using that procedure an auxiliary tire placard is allowed by NHTSA. It can be hand made and placed adjacent to the original tire placard. A notation should also be made in the vehicle owner’s manual.

Two very important tire industry standards to remember. 1. Always use replacement tires that provide load capacities equal to or greater than the OE tires. 2. Never use less inflation pressures than what has been recommended by the vehicle manufacturer or such pressures as amended by “Plus Sizing”.

It is wise to remember there are no provisions in FMVSS to inflate tires to the “load carried”. That procedure comes from the trucking industry where there are no rules for recommended inflation pressures.

All tires normally degrade. A tire that has degraded , say 5%, inflated to the load carried is automatically going to be overloaded. A tire loses 1.6% of its load capacity capabilities with every 1 PSI loss of recommended inflation pressure (RMA).

[itat]

For "P" passenger tires, always go with the max. pressure noted on the sidewalls. I agree with Kenny Kustom that an upgrade to "LT" light truck tires would be beneficial.

[Airdale]

Originally Posted by itat

For "P" passenger tires, always go with the max. pressure noted on the sidewalls. I agree with Kenny Kustom that an upgrade to "LT" light truck tires would be beneficial.

The vehicle certification label, tire placard and owner's manual always display the correct tire inflation pressures, even in Canada.

[Kf4mnc]

Originally Posted by Airdale

Normally the inflation pressures found on the tire placard (certification label) are appropriate all the way to the vehicle's GVWR. If they are not, the vehicle owner's manual will have the recommended pressures for towing conditions.

This is the BEST information for OEM tires.

When I upgraded to LT tires I emailed Michelin directly and told them my vehicle, original tires and new tires and they responded with the correct PSI. AND, if I recall correctly they let me know within 48 hours.

[Airdale]

Originally Posted by Kf4mnc

This is the BEST information for OEM tires.

When I upgraded to LT tires I emailed Michelin directly and told them my vehicle, original tires and new tires and they responded with the correct PSI. AND, if I recall correctly they let me know within 48 hours.

OEM recommended tire inflation pressures are not set by a tire manufacturer. They are always set by the vehicle manufacturer.

If you have changed tire sizes the installer should set new recommended tire pressures for tires of a different size and/or design.

The wording of your question to Michelin will determine their answer.

Did Michelin provide you with an answer that would require your replacement tires to have enough load capacity to equal or be greater than the OEM tires provided?

[itat]

Originally Posted by Airdale

The vehicle certification label, tire placard and owner's manual always display the correct tire inflation pressures, even in Canada.

The vehicle manufacturer's placard provides their "recommended" tire pressure for the best ride based on what they consider to be typical driving conditions. Yes, their recommended psi will be good up to the GVWR, but there is no reason you can't go with the max. pressure indicated on the tire sidewall for improved stability if you are at or slightly over the GVWR as is often the case. As long as we understand that it does nothing to increase the GVWR.

I upgraded my tires from P to LT and inflate the LT tires to 65 psi based on manufacturer's recommendations and my seat-of-the-pants feeling about performance based on experimentation. The LT tires can go up to 80 psi but I don't need that much pressure for my weight.

[Airdale]

Originally Posted by itat

The vehicle manufacturer's placard provides their "recommended" tire pressure for the best ride based on what they consider to be typical driving conditions.

In the world of tire inflation pressures, recommended and correct mean the same thing. Vehicle manufacturer's must use the rules as they apply to them. Inflation pressures set by vehicle manufacturers are not arbitrary, they are set in accordance with FMVSS 571.110 & 571.120.

Yes, their recommended psi will be good up to the GVWR, but there is no reason you can't go with the max.

That is true. However, going over GVWR is never recommended.

My messages are in green.

[Kf4mnc]

Originally Posted by Airdale

OEM recommended tire inflation pressures are not set by a tire manufacturer. They are always set by the vehicle manufacturer.

If you have changed tire sizes the installer should set new recommended tire pressures for tires of a different size and/or design.

The wording of your question to Michelin will determine their answer.

Did Michelin provide you with an answer that would require your replacement tires to have enough load capacity to equal or be greater than the OEM tires provided?

I was referring to the OEM recommendations by the manufacture for the OEM tires. Which you also stated in the post immediately preceding mine. I don't understand what you are questioning? We are saying the same thing?

Regarding the reply from Michelin, I have copied it below.

02/18/2015

Hello Chris,

Thank you for your email. We welcome the opportunity to serve you.


In regards to the email you sent stating:
---------------------------------------------------------------------
To Whom it May Concern,
I am writing in regards to a recent tire purchase I made. I am inquiring as to what the recommended tire pressure should be since I am not running the factory size tire on my vehicle. The specs are below:

Vehicle:
2008 Toyota Tundra Double Cab
4.7L 4X4

Original Factory Size:
P255-70-18
Recommended Factory Inflation:
30 PSI Front 33 PSI Rear

Current Size:
LT275-70-18
What would the recommend Inflation be for the new size?

Thank You for your help!

Chris

---------------------------------------------------------------------

The best air pressure recommendation for the original equipment size tires is to use the inflation pressure as specified by the vehicle manufacturer which can be found on the placard located on the driver’s door jam or in the vehicle owner’s manual. They have determined the optimal inflation pressure for load, ride, handling, rolling resistance and treadwear performance.

Maintaining correct tire inflation pressure helps optimize tire performance and fuel economy. Correct tire inflation pressure also allows you to experience tire comfort, durability and performance designed to match the needs of your vehicle.

Based on the original equipment tire size and inflation pressures of 30 psi front and 33 psi rear, we would recommend that you inflate your tires to 45 psi front and rear for comfort, handling; including even tire.

Michelin 1-866-866-6605

We appreciate your business.

It is our goal to ensure that your issue has been resolved or your question answered to your satisfaction. If we can assist you further, please respond to this email or call us at 1-866-866-6605 (toll free) between 8:00AM and 8:00PM Eastern Time Monday through Friday or between 8:30AM and 4:30PM Eastern Time on Saturday.

Sincerely,

Alvin

Folks really are making this more complicated than it should be. Go by what your manual states and you should be fine. Stating that people should have to contact each tire manufacture is just crazy. The vast majority of folks will not do that, so it is prudent that the manufacture provided accurate information. Now, should you replace their tires with none OEM equipment that is another story. At that point the owner is responsible for determining the appropriate pressure, at which point, may require contacting the tire manufacture and the vehicle manufacture.

[Airdale]

Originally Posted by Kf4mnc

I was referring to the OEM recommendations by the manufacture for the OEM tires. Which you also stated in the post immediately preceding mine. I don't understand what you are questioning? We are saying the same thing?

Regarding the reply from Michelin, I have copied it below.


Folks really are making this more complicated than it should be. Go by what your manual states and you should be fine. Stating that people should have to contact each tire manufacture is just crazy. The vast majority of folks will not do that, so it is prudent that the manufacture provided accurate information. Now, should you replace their tires with none OEM equipment that is another story. At that point the owner is responsible for determining the appropriate pressure, at which point, may require contacting the tire manufacture and the vehicle manufacture.

What I said.

If you have changed tire sizes the installer should set new recommended tire pressures for tires of a different size and/or design.

It is important to remember that OEM Passenger tires fitted to a pick-up truck MUST be degraded for fitment to the truck. Vehicle manufacturers will do the math when selecting the tire for fitment. The load capacity of the "P" tire at a given inflation pressure MUST be lowered by dividing the value found on the tire's load inflation chart by 1.1.

Excerpt from FMVSS 571.110, paragraph S4.2.2.2; When passenger car tires are installed on an MPV, truck, bus, or trailer, each tire's load rating is reduced by dividing it by 1.10 before determining the sum of the maximum load ratings of the tires fitted to an axle.

[DaveGray]

Here's all you need to know about tow vehicle and RV PSI.
http://fifthwheelst.com/step5.html

Sent from my VS985 4G using Tapatalk

[ilmor]

Originally Posted by Airdale

Normally the inflation pressures found on the tire placard (certification label) are appropriate all the way to the vehicle's GVWR. If they are not, the vehicle owner's manual will have the recommended pressures for towing conditions.

This is the answer.

[Tom48]

Originally Posted by Kenny kustom

I would swap out the passenger tires for a set of truck tires.


2016 Sabre 36QBOK
2015 Ram 3500 CUMMINS

X2 I did and feels good. My first towing with a 25 foot toy hauler was on 44 psi at PSI van tires . Was on 40 psi van tires. Blowout one trip flat tire next trip new tires third trip