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Old 11-11-2015, 06:47 PM
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Question what a good tire pressure for new BFGoodrich KO2

Hi all i need some help. I just install new 245/75R16 BFG KO2 tires. the shop that installed them put 50psi. I dont know if that to much pressure. I dont do no off road driving. just normal highway/road driving.

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Old 11-11-2015, 06:51 PM   #2
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50 psi is absurdly high, that shop is clueless... they probably just read the air pressure molded onto its sidewall which is never the correct normal pressure. That sidewall air pressure is just its maximum safe air pressure.

Your tires are 30.5 which is roughly equivalent to a 31" size where 30-31 psi is fine. There should also be a sticker on your door jam which gives the exact factory recommended air pressure which should include your 245/75/R16 size.

Vehicle weight determines the correct air pressure so that same size tire you're running would have 5 different correct air pressures with 5 different weight vehicles running it. The heavier the vehicle, the more air pressure that is required.

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Old 11-11-2015, 06:54 PM   #3
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Originally Posted by timothy View Post
Hi all i need some help. I just install new 245/75R16 BFG KO2 tires. the shop that installed them put 50psi. I dont know if that to much pressure. I dont do no off road driving. just normal highway/road driving.

Around 30 psi should be just about right. Even 35 psi on the road will be fine if you do a lot of highway driving.
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Old 11-11-2015, 07:00 PM
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Around 30 psi should be just about right. Even 35 psi on the road will be fine if you do a lot of highway driving.
ok i think 35psi will be fine.
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Old 11-11-2015, 07:02 PM   #5
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ok i think 35psi will be fine.
35 would be a little excessive for that size tire.
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Old 11-11-2015, 07:04 PM
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[QUOTE=Jerry Bransford;22445249]50 psi is absurdly high, that shop is clueless... they probably just read the air pressure molded onto its sidewall which is never the correct normal pressure. That sidewall air pressure is just its maximum safe air pressure.

Your tires are 30.5 which is roughly equivalent to a 31" size where 30-31 psi is fine. There should also be a sticker on your door jam which gives the exact factory recommended air pressure which should include your 245/75/R16 size.

Vehicle weight determines the correct air pressure so that same size tire you're running would have 5 different correct air pressures with 5 different weight vehicles running it. The heavier the vehicle, the more air pressure that is required.[/QUO

i dont have the sticker in my door jam. i think 31 psi will be fine
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Old 11-12-2015, 09:25 AM   #7
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30 or a hair below (28 lowest) is what I run, at least on my KOs. I found 35 to be a rougher ride, and 30 made a difference. My set of KOs lasted 86,000 miles but performance started to really drop off at 75,000. I only rotated my tires maybe 3-4 times. I JUST had KO2s installed, and havent had a chance to check tire pressure that was installed. Just the soft new rubber alone gave a better ride lol.
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Old 11-12-2015, 11:22 AM   #8
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I Run 25 rear, 28 front. They wear perfectly, I rotate,front to back every other oil change and adjust accordingly. I came up with there pressures by chalk test and then keeping a eye on wear. Got lots of miles on them and they looking great. This is on my 91 yj with heavy bumpers winch tire swing and so on. Every jeep is different though.
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Old 11-12-2015, 04:06 PM   #9
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Googled the tire and saw LT ,so your giiven 50 psi is C-load and the pressure at wich the maximum load can be carried up to 99m/h .
Also saw Loadindex 120 wich means maximum load 1400kg/3086lbs.
Also saw picture and this tire has large profile blocks that cover a part of the sidewall, from wich I concluded that they are allowed lesser deflection then the tire-maker calculated the maximum load for.

But even if you substract 20% to be in the clear with laws of nature, still 1120 kg/2460lbs a tire.
This is probably close to the GAWR so 1 tire can bare the maximum allowed weight on the axle.

This means that only half of the maximum load on one tire so needed pressure about half of 50 psi is 25 psi. This for up to 99m/h road driving speed.
And car fully loaded, wich most dont have in normal use.

But if you can produce these GAWR's front and rear, and while your are busy also GVWR, or empty weight and weight division and way you load it, so I can estimate the weight on the axles, I can calculate a save highest pressure for you, with still acceptable gripp and comfort .

Then also confirm the tire maximum load and AT-pressure ( wich is not the maximum allowed cold pressure of tire) and maximum speed of tire. Mostly can be found on sidewall.

Greatings from a Dutch Pigheaded self-declared tirepressure-specialist.
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Old 11-12-2015, 05:57 PM   #10
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Googled the tire and saw LT ,so your giiven 50 psi is C-load and the pressure at wich the maximum load can be carried up to 99m/h .
Also saw Loadindex 120 wich means maximum load 1400kg/3086lbs.
Also saw picture and this tire has large profile blocks that cover a part of the sidewall, from wich I concluded that they are allowed lesser deflection then the tire-maker calculated the maximum load for.

But even if you substract 20% to be in the clear with laws of nature, still 1120 kg/2460lbs a tire.
This is probably close to the GAWR so 1 tire can bare the maximum allowed weight on the axle.

This means that only half of the maximum load on one tire so needed pressure about half of 50 psi is 25 psi. This for up to 99m/h road driving speed.
And car fully loaded, wich most dont have in normal use.

But if you can produce these GAWR's front and rear, and while your are busy also GVWR, or empty weight and weight division and way you load it, so I can estimate the weight on the axles, I can calculate a save highest pressure for you, with still acceptable gripp and comfort .

Then also confirm the tire maximum load and AT-pressure ( wich is not the maximum allowed cold pressure of tire) and maximum speed of tire. Mostly can be found on sidewall.

Greatings from a Dutch Pigheaded self-declared tirepressure-specialist.
Ha ha, or just chalk em and move on. Bet I get 70k out of mine.
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Old 11-12-2015, 06:09 PM   #11
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Chalking is talked about a lot but in my personal opinion, basing a tire's air pressure on getting even wear off a chalk line most likely ends up with an underinflated tire. They draw a chalk line across the tread and then keep airing it down until all the chalk wears off evenly without realizing the edge of the tread of most tires isn't supposed to touch the ground.
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Old 11-12-2015, 06:16 PM   #12
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All I can say is it works! I'm a cheap sob and hate spending $ on tires. Been doing it that way for 20 some odd years, and never had a set of bfg's wear bad, uneven, or get less than 60k out of them. If the edges shouldn't be touching then the centers wouldn't be wearing well either.
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Old 11-12-2015, 06:18 PM   #13
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Also get abt 16-18 MPG on 33s in my 91 4.0 5sp.
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Old 11-12-2015, 06:29 PM   #14
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All I can say is it works! I'm a cheap sob and hate spending $ on tires. Been doing it that way for 20 some odd years, and never had a set of bfg's wear bad, uneven, or get less than 60k out of them. If the edges shouldn't be touching then the centers wouldn't be wearing well either.
The edges of the treads are for when you're cornering and the tire is rolling to the side. The entire tread should not be on the ground for most tires we use on our Jeeps.
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Old 11-12-2015, 07:22 PM   #15
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The edges of the treads are for when you're cornering and the tire is rolling to the side. The entire tread should not be on the ground for most tires we use on our Jeeps.
Why not? Doesn't accelerate wear, mine dont.

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