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.
What does the sticker on the door jamb say?
Not the factory tires, so the door jamb is not for those tires
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.
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.
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.
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.
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
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.
I run mine at 40-42 on my ‘10 F150
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.
55 front and 50 back with empty bed on a 2500HD, adjusted up loaded.
Run 44 psi on my Tundra. Got 64 K on the originals.
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.
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.
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.
No, LT-metric tires do not need less PSI than P-metrics to haul the same load. They need more.
I run mine at 37psig on my 2019 Jeep JL.
With the 265/65/18 Hankook ATMs I have on my truck now, 5 pounds less than the 50 PSI max listed on the sidewall data, in cool/cold weather. Summertime, 8 pounds less.
Had a set of BFG AT KOs on a half ton 4x4 back in 2002. Ran 'em at whatever the max sidewall pressure was. At maybe 50K miles and running the truck hard on a four lane, one front tire literally exploded. Ain't owned a BFG since. FWIW, they weren't worth all that much in deep mud or snow and that truck saw plenty of both.
In my 63 chevy i run 25 lbs.
In my 2015 f150 i run 40 but air them up when pulling a trailer.
With the 265/65/18 Hankook ATMs I have on my truck now, 5 pounds less than the 50 PSI max listed on the sidewall data, in cool/cold weather. Summertime, 8 pounds less.
Had a set of BFG AT KOs on a half ton 4x4 back in 2002. Ran 'em at whatever the max sidewall pressure was. At maybe 50K miles and running the truck hard on a four lane, one front tire literally exploded. Ain't owned a BFG since. FWIW, they weren't worth all that much in deep mud or snow and that truck saw plenty of both.
Preach!
Amen!
I've had good service from Cooper AT3s on my previous truck and them ol' Hancooks on my current ride They replaced the useless Goodyears that came on it new..
My first 4x4 was an '80 K10 Chebbie short box. Forget WTH they were called back then, but put a new set of fairly wide Firestone "off road" gums on it. Buddy had a set of Wranglers with a similar tread style on his '81. Both sets of tires shared the same problem: Hit an inch of standing water at speed and it was white knuckle time,
Tire makers eventually figured out it was a good idea to design a tread that actually allowed water to escape, so the sumbeeches didn't hydro plane..
Sorry,
Have been out of town.
The tires are BFG AT KO2, LT305/65R18 124/121R on a Silverado 1500 Trail Boss
5 pounds under max pressure on the sidewall.
Not BFG's but Brigstones on the wife's new SUV. 20's and H rated and it rides terrible at the door jam recommended 35 psi. H's are 134 mph rated tires and why do I need that on something that isn't going even half of that speed during its lifetime? I run Michlen P rated 20's on my truck and at 35 psi they ride just fine. S rated 19" Michelin tires on the same model older SUV and they ride way better than those Brigstone H's. I might be wrong, but aren't people looking for a smoother, quieter ride from their new car? I miss those 15, 16, 17 and 18" wheels with the more flexible tire sidewalls.
Update: I talked with a tire guy today and he said that I could reduce the tire pressure down to around 32 psi for a better ride, but he said that he wouldn't ever drop it lower than 30 psi.
They are about 38 PSI now. Might bump it up based on the responses. Just want to maximize the tread life as they are not cheap.
^^^^
That. Let the tire tell you how low it will let you run in pressure, for ride quality with and E rated and a 1/2 ton. Otherwise, you’ll be running it too stiff for a good ride or the suspension to like it, or too soft for good wear. ....at least that’s been best since a tire bud had me doing it for when I put bigger/stiffer tires on my lighter Toyotas and such.
On our 2012 Tundra with 213,000+ miles on the odometer, I am on my third set. FWIW. I have been running them at 40 psi on the highway, but air them up to 50 when we go somewhere off road with a lot of rocks. I have never had a problem, but my wife has ruined two over the years while driving on rough backcountry "roads" that are not regularly maintained.
Jeep xj and cj.....31 x 10.50s.
35 on street. 15 -20 wheeeling ( reg 8 inch rims ).
Reg BFG AT and KO.....even wear....lucky to het 30k out of a set.
Ride good. Did ok offroad to 50%.
Switched to Goodyear MTR. Sucked on wet pavement, but better everywhere else. 40k amd no flats. Cost more.
Got cheap Mastercraft going on the Jeep this week