KO2 tire pressure - psi
- Thread starter Maxb
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I run mine at 35lbs
Door jamb is for P275/60R18 (passenger car) tires. The LT275/70R18 KO2 are (light truck) E load range tires. Apples & Oranges. Depending on circumstances, I tend to run 35PSI (city), and 40PSI (long distance), although I believe 40PSI is the official recommendation, for conversion from P-series to LT-series tires.
Not really a significant difference, a bigger difference between P & LT construction. In an ideal world, for my use case, I’d lean 17” LT285/70R17 in a load range C, on an ET40-50 17x8 wheel.
That’s all that I could find, when I was looking. Same for LT285/75R16 on my other two.
The only way to do it right, is determining the axleloads 99% acurate, and look them back in a cold pressure/axleloadcapacity list, I can make for your tire, with build in maximum reserve, at wich comfort and gripp is still acceptable.
A C- load LT or eur equivalent C(omercial) needs higher pressure for the same load on tire, because lesser surface on the ground at same deflection.
The recomended pressures are for OEM - tires, and GAWR's with no reserve calculated for max technical carspeed.
If calculated, nowadays more often referencepressure of oem tire.
So if you see 35,36,41 or 42 psi, calculated for GAWR's, even with my reserves, could come lower, mayby in the 20s psi.
To make a list, I need next of tires.
1. Maximum load or loadindex
2. Kind of tire to determine referencepressure
3. Speedcode, less important, shal be Q or above, for wich maxload is given for 160kmph/99mph.
Then your task is "ONLY" to determine the axleloads in your use 99% acurate, the most tricky part, and your responcibility.
What pressures others use, does not automatically mean its good for your situation.
A C- load LT or eur equivalent C(omercial) needs higher pressure for the same load on tire, because lesser surface on the ground at same deflection.
The recomended pressures are for OEM - tires, and GAWR's with no reserve calculated for max technical carspeed.
If calculated, nowadays more often referencepressure of oem tire.
So if you see 35,36,41 or 42 psi, calculated for GAWR's, even with my reserves, could come lower, mayby in the 20s psi.
To make a list, I need next of tires.
1. Maximum load or loadindex
2. Kind of tire to determine referencepressure
3. Speedcode, less important, shal be Q or above, for wich maxload is given for 160kmph/99mph.
Then your task is "ONLY" to determine the axleloads in your use 99% acurate, the most tricky part, and your responcibility.
What pressures others use, does not automatically mean its good for your situation.
I run mine around 27 psi, it's comfy
I ran 40 when I had KO2s and am still running 40 with my cooper discover at3 xlt
FWIW I run 40 unless winter, and then down to 35. Don't do alot of off road, more of a fam adventure wagon at this point. I notice a little less forgiveness when at 40 (which may be all in my head). Lastly - I have a full size spare that I rotate in at every oil change. With about 40k miles on the set I'm still at 11/32 all around. Which feels good on a 50k tire. I know there is tribalism around whether or not to do this, but I'm a fan of the extra life it brings to the set.
Use this link to calculate what you need. The stock tire likely has a different rating, so the door jam tire pressure are off!
The calculator in the link uses all specs/ sizes/ numbers of the old tire and compares to the new tire specs.
tiresize.com
The calculator in the link uses all specs/ sizes/ numbers of the old tire and compares to the new tire specs.
Tire Pressure Calculator
Easy to use tire pressure calculator. Use our tire pressure calculator to calculate the new tire pressure needed when changing tire sizes.
I run ~35psi on my 305/55/20 KO2’s, unless I’m off-road in sandy conditions, then more like 25psi.
I've run 32-40psi on all 3 sets of 275/70/18 BFG KOs, KO2s - for a little over 150,000 miles. No discernible difference in feel. I do think the current tires, as much as I love the BFGs, will be the last BFGs. The E-rated tires are just too heavy and stiff. I knew this all along, but I recently put C-Rated 265/70/17 BFG KO2s on my 2020 4Runner... and was surprised how much smoother they are. I drove the 100 yesterday and wondered how I tolerated that ride for that long.
I do love how the KOs look though
I do love how the KOs look though
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I run mine at 32 psi, ran them at 40 before but the ride felt a good bit harsher to me.
Yeah 32-35 over here. 18psi off-road.
GTV
SILVER Star
Anyone here tried the chalk test on a 100? I'm gonna give it a shot, I'm curious where it ends up.
Jack90210
SILVER Star
29psi on this LT-rated tire is a dangerously low pressure.
To simply maintain the load-carrying equivalent of the factory (doorsill) P-rated recommendation of 29f/32r on a 275/70-18 LT-rated tire,
you should run 35psi front, 37psi rear.
To be more complete, 35psi on an LT-rated KO2 will handle the equivalent load of a P-rated, OEM-sized tire running the factory-suggested 29psi up front. Use the tire pressure calculator posted above (screenshot below).
I run my C-rated LT285/70R17 KO2s at 40psi both front and rear, more if I am towing; the factory recommendation seems low to me. I've never had any problems with uneven wear, and 40psi is plenty comfortable IMO.
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