Concerned about new tire purchase!

[lpennock]

Easy starting point for your tire pressure. Pull the tire size and pressures off the door jam and plug them into this Tire Pressure Calculator. I would run the rears lower than the door jam pressure as that pressure assumes the truck is fully loaded. For a LT315/70-17 I would probably start at 35psi which wii support a 2535x2=5070lb axle weight.

 

[62Blazer]

Easy starting point for your tire pressure. Pull the tire size and pressures off the door jam and plug them into this Tire Pressure Calculator. I would run the rears lower than the door jam pressure as that pressure assumes the truck is fully loaded. For a LT315/70-17 I would probably start at 35psi which wii support a 2535x2=5070lb axle weight.

I understand what you are saying. However just to make it clear for somebody else maybe reading this post, they are not saying to run the tire pressures shown on the door jam which only pertain to the original tires size and load rating, but the posted calculator will "translate" the pressure of the original tires to what is needed for a different size and/or load rating tire.

The calculator can be useful if you have an "idea" air pressure for the current tires (not the door sticker, but what works the best in real life) and want to get a baseline for a different size or load rating tires.

 

[lpennock]

I understand what you are saying. However just to make it clear for somebody else maybe reading this post, they are not saying to run the tire pressures shown on the door jam which only pertain to the original tires size and load rating, but the posted calculator will "translate" the pressure of the original tires to what is needed for a different size and/or load rating tire.

The calculator can be useful if you have an "idea" air pressure for the current tires (not the door sticker, but what works the best in real life) and want to get a baseline for a different size or load rating tires.

The Door jam pressure is usually pretty close to ideal with a margin of error on the front axle. For my 3500 the door jam was 80 psi but after weighting the truck and looking at the load tables the minimum pressure for the Axle Weight was 72psi. So now I run about 78. Unless the person is going to get the truck weighted at a CAT scale and look up the load tables I will still recommend the door jam pressure and tire size as the starting point for the calculator.

The rear axles aren't close unless the truck is loaded as TRA managed to get a ruling passed that required the door jam pressure to be for the maximum GAWR.

Both my 06 3500 and 18 DRW came in under 3500lb unloaded axle weights. So when I make a rear psi recommendation I will use 2000lb (margin of error) to look up the pressure in the load tables. Since the load tables I have for a LT don't go below 35 psi I won't recommend below 35psi even though the tires can be run lower if someone does calculation.

 

[62Blazer]

The Door jam pressure is usually pretty close to ideal with a margin of error on the front axle. For my 3500 the door jam was 80 psi but after weighting the truck and looking at the load tables the minimum pressure for the Axle Weight was 72psi. So now I run about 78. Unless the person is going to get the truck weighted at a CAT scale and look up the load tables I will still recommend the door jam pressure and tire size as the starting point for the calculator.

The rear axles aren't close unless the truck is loaded as TRA managed to get a ruling passed that required the door jam pressure to be for the maximum GAWR.

Both my 06 3500 and 18 DRW came in under 3500lb unloaded axle weights. So when I make a rear psi recommendation I will use 2000lb (margin of error) to look up the pressure in the load tables. Since the load tables I have for a LT don't go below 35 psi I won't recommend below 35psi even though the tires can be run lower if someone does calculation.

The tire pressures listed are ideal pressures if you are running at the maximum load of the truck. Having the rear tires at 80 psi on an empty pickup truck is in no way ideal. Fully loaded, I will agree it is close.......but not empty.

 

[lpennock]

The tire pressures listed are ideal pressures if you are running at the maximum load of the truck. Having the rear tires at 80 psi on an empty pickup truck is in no way ideal. Fully loaded, I will agree it is close.......but not empty.

We are in total agreement on the Rears. The jam pressures are way high for unload.

I'm saying that the fronts are close enough as there is only about 5-600 lb axle weight difference between unloaded and rated GAWR, at least with a Cummins up there.

 

[olyelr]

The Door jam pressure is usually pretty close to ideal with a margin of error on the front axle. For my 3500 the door jam was 80 psi but after weighting the truck and looking at the load tables the minimum pressure for the Axle Weight was 72psi. So now I run about 78. Unless the person is going to get the truck weighted at a CAT scale and look up the load tables I will still recommend the door jam pressure and tire size as the starting point for the calculator.

The rear axles aren't close unless the truck is loaded as TRA managed to get a ruling passed that required the door jam pressure to be for the maximum GAWR.

Both my 06 3500 and 18 DRW came in under 3500lb unloaded axle weights. So when I make a rear psi recommendation I will use 2000lb (margin of error) to look up the pressure in the load tables. Since the load tables I have for a LT don't go below 35 psi I won't recommend below 35psi even though the tires can be run lower if someone does calculation.

The door jam sticker goes right out the window when you swap different size tires with different load ratings. Period. They no longer exist lol.

 

[lpennock]

The door jam sticker goes right out the window when you swap different size tires with different load ratings. Period. They no longer exist lol.

Not so they are the data to use the calculator with.

 

[ryanpaulaf1]

I've been running 40 front and about 35-38 rear for about 2 weeks now and I personally love the way they feel. The truck rides so so much better than my previous E rated tires. I love them so far. Can't wait for the winter time now.