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Just bought a used truck that has a pretty new set of BFG AT KO2. The sidewall says 65 psi max. They are currently at 38 psi.
For those of you who have or have had these tires, what PSI did you run them at?
Thanks.
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What does the sticker on the door jamb say?
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Not the factory tires, so the door jamb is not for those tires
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Campfire Outfitter
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I run mine about 5 lbs. under max pressure cold. If I'm off-road I will sometimes lower them to 30 lbs. depending on terrain. If I'm pulling a trailer the rears are at max.
Let's Go Brandon! FJB
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Campfire 'Bwana
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Camp is where you make it.
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OK...I have KO2’s and run 70 in the back, 60 in the front. But I suspect I have different truck and size/load rating KO2’s than you.
Looking for blanket recommendations on what pressure to run your KO2’s at without any info on tire size or even what vehicle they are going on is not going to get you much. If they are the same size and load rating as the factory tires, the sticker on the door jamb is a good place to start.
If they are bigger, you may be able to run them at lower pressure and achieve the same load rating as the factory tires. If they are LT rated tires and they are replacing tires that were originally P rated, you have to run more pressure than the p-rated tires to achieve equal load ratings (contrary to most people’s intuition). Regardless, you don’t want to exceed the pressure rating of your tires and valve stems.
There are charts that help you figure it all out, but with zero information on your setup. no one can really offer you any meaningful advice.
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I got some for my 2011 Ram 1500 (now traded off) and I think I got the best ride between 40 and 45psi which was 5-10 higher than the door jamb recommended. You need to go higher if you will be hauling heavy loads.
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Campfire Outfitter
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65# max would give you a "D" rated 8-ply equivalent tire. The door jamb still applies as a guideline as your entire suspension system is designed around the amount of flex/spring rate the factory supplied tires had @ that pressure. If you've got a 1/2T that came with 4 or 6 ply rated tires, the 8-ply you have now will ride a little stiffer, even @ door-jamb pressures. If you have a 3/4T or 1T pickup that's supposed to have "E" rated 10-ply, those 8's are gonna feel squishy.
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Never run them at max. If pulling and fully loaded give yourself at least 3-5lbs for expansion from heat.
Empty I run all my E-10s at 75-80% of max. Lower end on halftons higher on the 3/4s
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Exactly. This question is like asking "what powder charge should I use in my gun?" We have no idea what the gun is. OK...I have KO2’s and run 70 in the back, 60 in the front. But I suspect I have different truck and size/load rating KO2’s than you.
Looking for blanket recommendations on what pressure to run your KO2’s at without any info on tire size or even what vehicle they are going on is not going to get you much. If they are the same size and load rating as the factory tires, the sticker on the door jamb is a good place to start.
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I run mine at 40-42 on my ‘10 F150
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Never run them at max. If pulling and fully loaded give yourself at least 3-5lbs for expansion from heat. This is untrue. They are designed to be safely inflated up to and including the stated maximum cold tire pressure. Pressure increase due to heat from driving is accounted for in this. It is perfectly safe to set to Max cold psi and tow all you want. The hot pressure will be higher than the stated cold max, but the tire is designed for that. If it makes you sleep better, let a few pounds out but you are actually lowering the maximum weight capacity of the tire when you do that. How much depends on the size. The Toyo tables posted are a good place to start.
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55 front and 50 back with empty bed on a 2500HD, adjusted up loaded.
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Run 44 psi on my Tundra. Got 64 K on the originals.
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If on a 1/2 ton truck around 35 PSI is a good place to start. With some experimenting you may need to tweak that up or down. When running factory P series tires on a 1/2 ton 35 PSI will give the best ride, but the sidewalls suggest 44 PSI for heavy loads. I always ran closer to 40 PSI with P series tires. The ride was a little stiffer, but I got better fuel mileage, didn't have to air up when I hauled a load, and still got 60K out of a set of tires. LT tires are stiffer and actually need LESS air to haul the same weight. The tire store put 50 PSI in mine when they mounted them. About right for an unloaded 3/4 ton. But I found the best ride at about 30 PSI. With the LT"s at 35 PSI they ride about the same as P's at 40 PSI and will carry more weight than a 1/2 ton is rated for at 35 PSI.
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Never run them at max. If pulling and fully loaded give yourself at least 3-5lbs for expansion from heat. This is untrue. They are designed to be safely inflated up to and including the stated maximum cold tire pressure. Pressure increase due to heat from driving is accounted for in this. It is perfectly safe to set to Max cold psi and tow all you want. The hot pressure will be higher than the stated cold max, but the tire is designed for that. If it makes you sleep better, let a few pounds out but you are actually lowering the maximum weight capacity of the tire when you do that. How much depends on the size. The Toyo tables posted are a good place to start. What is untrue? I was giving my opinion based on almost million miles driving over the last 35 years hauling and towing.
"Maybe we're all happy."
"Go to the sporting goods store. From the files, obtain form 4473. These will contain descriptions of weapons and lists of private ownership."
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I thought it was pretty simple. The statement about never run them at max because you need to give yourself some room for the heat to increase pressure is not supported by any tire manufacturers. Cold max pressure is just that. It is safe to set your tires to cold max and load up to max gvwr and drive. No tire manufacturer says to set them less than max because the pressure will rise when you drive. They build that into their calculations when they set max psi.
If you lower pressure you reduce load capacity, albeit not very much for only a few psi. Like I said, if it makes you feel better go ahead and do it, but you don’t have to to be safe. Given today’s tires typically far exceed the required load of today’s trucks, running them lower than max is almost always just fine.
Last edited by K1500; 09/14/19.
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No, LT-metric tires do not need less PSI than P-metrics to haul the same load. They need more.
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I run mine at 37psig on my 2019 Jeep JL.
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