Tow vehicle tire pressure

[TSRig18]

Good morning - I have a new to me 2021 GMC Sierra 3500 dually. The previous owner had put new tires on which were much larger than the OEM. The placard on the door jam states that the tires should be run at 80 psi, the new tires have on their sidewall a pressure of 65 psi. I am getting conflicting info as to what pressure to actually run them at. I would appreciate any info you could share.

Cheers

Tim

[FT4NOW]

You could look up the loading/inflation chart for your specific tires, and as long as you know the weight of the truck you could figure out where to set the pressure. A CAT scale would be helpful in this case, if you have no idea on weight, you could base it off the GVWR of the truck, most likely 14k lbs for a dually.

[TSRig18]

thanks for that - will do.

[Hoopy Frood]

Sounds like the PO replaced the "E" rated tires with "P" rated passenger tires. If so, the ride will be much softer, but the towing will suffer due to the softer sidewalls and lower inflation pressure.

[xrated]

Good morning - I have a new to me 2021 GMC Sierra 3500 dually. The previous owner had put new tires on which were much larger than the OEM. The placard on the door jam states that the tires should be run at 80 psi, the new tires have on their sidewall a pressure of 65 psi. I am getting conflicting info as to what pressure to actually run them at. I would appreciate any info you could share.

Cheers

Tim

I would be concerned with the tires that are on the truck now. You need to look up the rated load capacity of the tire at the maximum inflated psi. If all four tires on the rear of the truck are equal to or less than the Rear Axle Weight rating, they need to go, and be replaced with tires that are equal to OEM tire ratings and spec. Same thing with the front tires.

In the line of progression, as far as capacity ratings go, payload for the truck is the starting point. Then the RAWR, then the tire load capacity rating....which should ALWAYS be higher than the RAWR....by at least some amount.

[FT4NOW]

Excellent points about which tires the previous owner installed. Hope you dont need to replace them, that's a good $1200 - 1500.

[Rabbit]

All good points being made. Sounds like the tires are not appropriate for your vehicle. Regardless, go by the pressure on the tire, not on the door label as you don’t have the OEM tires.

[TSRig18]

Thank you, that was good info. I did go onto the tire manufacturer's website to check the max load per tire, which is 2910lb. The RAWR is 10,500 so we are good there. It still begs the question though, do I follow the info on the tire as to the pressure they should be inflated to. A gentleman at the GM dealership said they should be inflated to 80psi as per the placard on the doorframe (even though they are not the OEM tires)???

[FT4NOW]

Thank you, that was good info. I did go onto the tire manufacturer's website to check the max load per tire, which is 2910lb. The RAWR is 10,500 so we are good there. It still begs the question though, do I follow the info on the tire as to the pressure they should be inflated to. A gentleman at the GM dealership said they should be inflated to 80psi as per the placard on the doorframe (even though they are not the OEM tires)???

If it were me, I'd still go off what the tire manufacturer says per their tables. Just because someone at a dealership tells you something, doesn't make it right....especial if they were from the sales department. Maybe someone else has a better idea.

[Hoopy Frood]

If the tire says "Maximum Pressure is 65 psi", why would you think the tire should be inflated to 80 psi? What tire size does the placard call for, and what tire size is presently on the truck?