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New LT275/65R18 BFG KO2's today

FL335i

By FL335i
in Modifications & Accessories

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FL335i Enthusiast

FL335i

Posted
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Threw them on today. Running them on the factory 18" wheels. No rubbing so far, they are +1 size, should not rub. I think they look great and ride even better. I actually like the stiffer tire. I feel more connected to the road. the SRA's felt like pillows. Currently running 45psi in the front, 40psi in the rear as I'm empty 90% of the time. I'll get some pics up later. The OEM SRA's were rated for 2,469 Lbs @ 51psi. GM's door sticker called for 35psi. The door sticker says 3,950 Lbs per axle for max gross weight. I found a few inflation charts for E rated LT275/65R18 and they show 40psi as being plenty, 45psi if I'm really wanting to error on safety's side when loaded. I've also put some paint marker stripes on the treads. See how the 45F/40R does on wear pattern. But somewhere in the area of 40-45 is where I'll be running them.

Waaazooo Senior Enthusiast

Waaazooo

Posted
Posted

I run 275/65-20 without rubbing as well. They came from tire rack inflated to 80psi. Which was like a flintstone ride... Lowered them down to 45 all around, much better than 80

 

 

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OldBlue61 Enthusiast

OldBlue61

Posted
Posted

Interested in feedback on how the 40-45psi works in the +1 size. Seems like a good range to run them at.

FL335i Enthusiast

FL335i

Posted
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Today the 45/40 combo did great in daily driving. I noticed the fronts heated up to 49psi and the rears to 43 while driving. I might try 42 up front see what that does. By the time I got to work both F&R paint marker stripes were gone.... might have to mark them up and just drive a few miles around the neighborhood.

FL335i Enthusiast

FL335i

Posted
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Drove them today from Tampa to St Pete on the highway. Had them up to 80 mph for a short time to test for vibration, cruised around 77. I am very impressed with the highway ride. Super smooth and quiet. The funny thing is these KO2's are smoother on the highway than compare to the OEM SRA's. I had no vibration today, in the heat of the day, running on the hwy which normally produced a slight chevy shake from the rear. These Ko2's are definitively a top shelf tire. Around town with bumpier roads, pot holes, speed bumps etc you can tell they are stiffer and heavier than the SRA's and the steering input is diminished also, but that's expected from a larger, heavier, knobby E load tire compare to bald SRA's. I'm sticking with the 45psi in the front, 40 in the rear. When I tow or load up I'll air the rears up to 45. Similar to what I was doing with the SRA's.... 35 in the front, 32 in the rear. Same % difference. Treat pattern looks even on both front and rear. Braking is very good on these tires from what I've experienced so far. Very confident braking. Thus far I am very pleased with these tires. I can see why this tire has a large following. If they continue to treat me as well as they have in the first 500 miles, I've got my tire for life.

  • 2 weeks later...
TeamGoose Enthusiast

TeamGoose

Posted
Posted

Threw them on today. Running them on the factory 18" wheels. No rubbing so far, they are +1 size, should not rub. I think they look great and ride even better. I actually like the stiffer tire. I feel more connected to the road. the SRA's felt like pillows. Currently running 45psi in the front, 40psi in the rear as I'm empty 90% of the time. I'll get some pics up later. The OEM SRA's were rated for 2,469 Lbs @ 51psi. GM's door sticker called for 35psi. The door sticker says 3,950 Lbs per axle for max gross weight. I found a few inflation charts for E rated LT275/65R18 and they show 40psi as being plenty, 45psi if I'm really wanting to error on safety's side when loaded. I've also put some paint marker stripes on the treads. See how the 45F/40R does on wear pattern. But somewhere in the area of 40-45 is where I'll be running them.

Pics?? I bought the Bilstein 1500 adjustable ride height shocks to give me 1.8" in the front and bought the Bilstein 1500 to replace my back ones. Thinking of running 275/70r18 KO 2s. Would like to see what the 65s look like compared to the 70s.

 

 

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silveradosid Senior Enthusiast

silveradosid

Posted
Posted

just put 275-75-17 on my truck today. would you recommend the same pressures, they are E ratted. they do make alot more noise than the goodyear fuel max tires i had on

Cowpie Senior Enthusiast

Cowpie

Posted
Posted

I have LT275/70R18 BFG AT KO2's on my 2500, one size up from the LT265/70R18's that came from the factory. A much nicer tire than the stock Michelins LTX AT2's. I also run the tire pressures down. On my 2500 when empty or light loaded, I typically run 50-55 psi in them. Not the stupid 60F 70R that GM recommends. That OEM recommendation is psi for max gross. The BFG AT KO2's are superb for the gravel roads I have to drive on daily and off road farm/ranch stuff. Much more sure footed and a really nice ride. And even very impressive as a highway tire. Pretty quiet for a E rated AT tire. Turned my 2500 into a different pickup compared to the stock tires.

 

Just because a tire is rated for 80 psi doesn't mean that is what they should be run at. My semi truck tires are rated for 120 psi, but the tire manufacturer load pressure charts show that I should run 95-98 psi for the gross loading I do, 17,000 lb per axle. Must be pretty good recommendation as I got 447,000 miles out of the last set of drive tires on that semi. I have found that by running lower pressures on my pickup when empty or light loaded, I have less wheel hop on bumpy roads which improves tire wear and even fuel economy by a little because the traction control is not having to micro manage those wheel hop events. Also overall handling, braking, etc is markedly improved. Let's face it, when a tire is properly inflated for the load that is on it, it is much better to get the pickup stopped when you need to.

 

It has been recommended, and I concur, that to determine the best inflation on the tire without the benefit of a tire manufacturer load/pressure chart, make a couple of chalk lines across the width of the tread and move the vehicle about 100 ft or so. Check the chalk lines. If there is nice uniform wear on the chalk lines, you have the best pressure. Uneven wear then not. If center of the chalk line is rubbed off more than the edges, too much inflation. Edges more than the center, under inflated. A good average person way of determining the best pressure for that tire on your vehicle.

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