Correct tire pressue under load?
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Senior Member
Joined: Oct 2008
Posts: 3,121
Likes: 4
From: Burlington, VT
Correct tire pressue under load?
I normally keep my tires at about 38 - 40 PSI. Now that I'm towing a 5x8 UHaul and I have a full bed, I notice the tires look a little flat. But when I check them pressure when cold, it reads 44PSI front and back. Last time I filled them it was at 39 PSI all around. Did the pressure go up because of the load? I made sure to check the pressure when the truck had been sitting overnight.
Anyway, just curious what the best pressure would be. Should I add air, remove air? As I said, they do look a little flat in the back but read over 40 PSI.
Thanks.
Anyway, just curious what the best pressure would be. Should I add air, remove air? As I said, they do look a little flat in the back but read over 40 PSI.
Thanks.
Senior Member
Joined: Dec 2008
Posts: 161
Likes: 0
From: Colorado Springs
I normally keep my tires at about 38 - 40 PSI. Now that I'm towing a 5x8 UHaul and I have a full bed, I notice the tires look a little flat. But when I check them pressure when cold, it reads 44PSI front and back. Last time I filled them it was at 39 PSI all around. Did the pressure go up because of the load? I made sure to check the pressure when the truck had been sitting overnight.
Anyway, just curious what the best pressure would be. Should I add air, remove air? As I said, they do look a little flat in the back but read over 40 PSI.
Thanks.
Anyway, just curious what the best pressure would be. Should I add air, remove air? As I said, they do look a little flat in the back but read over 40 PSI.
Thanks.
Senior Member
Joined: Dec 2007
Posts: 277
Likes: 2
From: San Antonio, TX
One thing to consider is temperature difference. You check tire pressure "cold" because air volume increases as it heats up. Your load will not affect your pressure that much. 5psi is around 15%+ variance on 39-40 psi. Consider out side air temp, gauge reading difference, and the load will make only minimal difference, but all these things can add up.
If you are that worried about it just make sure you are consistant and use the recommend psi that the label says on the door jam. Your vehicle weight max towing load and GVW are all considered when a pressure is determined.
If you are that worried about it just make sure you are consistant and use the recommend psi that the label says on the door jam. Your vehicle weight max towing load and GVW are all considered when a pressure is determined.
Senior Member
Joined: Dec 2003
Posts: 6,550
Likes: 2
From: Mount Airy,MD
If I remember correctly, the stock Hankooks had a max pressure of 35. At least those on my 07 had that max and the door sticker recommended was 35. Use what is on the door sticker if it is OE. That will handle anything within your trucks rated capabilities.
Senior Member
Joined: Sep 2005
Posts: 2,723
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From: Rich, Virginia
Some will keep [not exceed] their tire pressure at the recommended PSI written on the placard inside the door pillar when towing.
Some will run their pressure at the maximum PSI rating stated on the tire's sidewall when towing [80PSI on many tires]. Many, though, will tell you at this pressure, you will have very uneven tire wear [the centers will wear out much quicker than the lateral part of the tire] very quickly especially on radials.
Some will run a mucher higher PSI on the rear [load] then the front when towing.
It's really personal preference.
Whichever way you go, follow tim98's advice above.
Some will run their pressure at the maximum PSI rating stated on the tire's sidewall when towing [80PSI on many tires]. Many, though, will tell you at this pressure, you will have very uneven tire wear [the centers will wear out much quicker than the lateral part of the tire] very quickly especially on radials.
Some will run a mucher higher PSI on the rear [load] then the front when towing.
It's really personal preference.
Whichever way you go, follow tim98's advice above.