What is the optimal Tire Pressure one should be on?

[KinkyDuramax]

After purchasing a 23' Sierra I noticed that my other truck 20' Sierra that had a leveling kit added to it, and new tires (AT3Ws) the shop has set the PSI to 60. Whilst my new truck (23) is on A/T tires as well is set to 30-35PSI (depending on the cold/winter).

 

So, just for regular use - driving (not towing, or loading up the bed) what is the optimal tire pressure one should do? 

The 20' is going in for a recall to a GM dealership, figured I'd have them deflate it to the proper pressure.

 

I'm no mechanic - but 60PSI seems high for these tires for regular use. Logically to me if the tires are deflated they should be able to stick to the ground more providing more traction especially in these winter months, and just daily usage. With it being 30-35 PSI on my 23' I notice about 17-19 mpgs. I don't notice much of a difference in the 20' in terms of MPGs to PSIs.

 

I'm eager to see what folks have to say. 

[newdude]

35 minutes ago, ARedSierra said:

After purchasing a 23' Sierra I noticed that my other truck 20' Sierra that had a leveling kit added to it, and new tires (AT3Ws) the shop has set the PSI to 60. Whilst my new truck (23) is on A/T tires as well is set to 30-35PSI (depending on the cold/winter).

 

So, just for regular use - driving (not towing, or loading up the bed) what is the optimal tire pressure one should do? 

The 20' is going in for a recall to a GM dealership, figured I'd have them deflate it to the proper pressure.

 

I'm no mechanic - but 60PSI seems high for these tires for regular use. Logically to me if the tires are deflated they should be able to stick to the ground more providing more traction especially in these winter months, and just daily usage. With it being 30-35 PSI on my 23' I notice about 17-19 mpgs. I don't notice much of a difference in the 20' in terms of MPGs to PSIs.

 

I'm eager to see what folks have to say. 

 

 

Are they LT tires with a higher load rating?  D or E load for example?  

[KinkyDuramax]

13 minutes ago, newdude said:

 

 

Are they LT tires with a higher load rating?  D or E load for example?  

The tires on the truck according to an invoice is LT285/55R/20 FALK WP A/T3W E BW. 

[newdude]

10 minutes ago, ARedSierra said:

The tires on the truck according to an invoice is LT285/55R/20 FALK WP A/T3W E BW. 

 

 

Gotcha.  

 

So.  When you step up from a P tire to an LT tire, you should inflate to equate the load rating of the original tire.  So if you are on stock 20" wheels, your stock tires are P275/60R20.  At 35psi cold, the load rating in lbs is 2601lbs per tire.  Your new tires should be inflated to reach or exceed 2601lbs to ensure proper weight capacity matched to the OE tires.  

 

At 65psi, the effective load rating of the LT285/55R20 E is 2600lbs per tire.  So your cold PSI should be no less than 65psi to equal your new tires to the old tires.  If you aren't hauling heavy, could you drop to 50-60psi?  I suppose so sure, but when loading the truck (towing, etc.) I'd take them back to 65psi.  

 

Chart I use is from Toyo - Application of Load Inflation Tables Version 2020-7 (toyotires.com)

 

Yes, you have Falkens but Toyo is the only one I can find with detailed chart that shows this.  

Edited December 7, 2023 by newdude

[KinkyDuramax]

20 minutes ago, newdude said:

 

 

Gotcha.  

 

So.  When you step up from a P tire to an LT tire, you should inflate to equate the load rating of the original tire.  So if you are on stock 20" wheels, your stock tires are P275/60R20.  At 35psi cold, the load rating in lbs is 2601lbs per tire.  Your new tires should be inflated to reach or exceed 2601lbs to ensure proper weight capacity matched to the OE tires.  

 

At 65psi, the effective load rating of the LT285/55R20 E is 2600lbs per tire.  So your cold PSI should be no less than 65psi to equal your new tires to the old tires.  If you aren't hauling heavy, could you drop to 50-60psi?  I suppose so sure, but when loading the truck (towing, etc.) I'd take them back to 65psi.  

 

Chart I use is from Toyo - Application of Load Inflation Tables Version 2020-7 (toyotires.com)

 

Yes, you have Falkens but Toyo is the only one I can find with detailed chart that shows this.  

 

Sounds good. I'll drop them down to 45-50PSI and see how that performs. Thankfully, I can always stop by the dealership and have them inflate/deflate for free. It just super confusing for someone who knows nothing about tires aside from which brand is better/worse. I could see where it's important if towing. 

[Vincej138]

45-50 psi is still super high. Its gonna ride hard unloaded. The Falken have a very rigid sidewall, I would drop them to about 40psi. You could even go lower if you want. We always set E-rated tires on newly lifted vehicles in the 35-40 range. Can air up to 50-60 if towing big load. But around town, get the better feel. 

 

I run my 315/70/17 Nitto's around 37psi cold.