265/65R18 to 275/65R18, reprogram needed?

titan01 · April 22, 2015

Have a new 2015 Sierra All Terrain. Want to replace the stock SR-A's with some BFG KO2's. If I go slightly bigger to a 275/65R18 would I need to get a reprogram for the 1/2" diameter size difference? Or is it not enough difference to matter. Gotta think that any tire loses 1/2" diameter as it wears down anyways?

Thanks

Big Whiskey · April 23, 2015

I did the same thing on my truck, and didn't reprogram anything. You'll be just fine. Your speedometer might be 1-2 mph off at 70 mph, but you won't notice it at lower speeds.

titan01 · April 23, 2015

Good to hear, thanks! Nice rims by the way.

Big Whiskey · April 24, 2015

Good to hear, thanks! Nice rims by the way.

No problem. And thank you!

bcbz71 · May 21, 2015

Have a new 2015 Sierra All Terrain. Want to replace the stock SR-A's with some BFG KO2's. If I go slightly bigger to a 275/65R18 would I need to get a reprogram for the 1/2" diameter size difference? Or is it not enough difference to matter. Gotta think that any tire loses 1/2" diameter as it wears down anyways?

Thanks

I went to the same size in p-metric and the dealer reprogrammed for me for free but honestly, I don't think it makes much difference as the All Terrain Sierras with 20s are the same size as the 275/65r18.

Those BFGs in 275 are gonna look skinnier than your stock SRAs in 265. You can go 285 in BFG without a level.

titan01 · May 21, 2015

Had the 275 BFG KO2's on for around 2 weeks now, love them. The old KO's might have looked skinny but the new KO2's definitely do not, they are real beefy. Look way better than the stock SRA's.

cuttingedge · May 22, 2015

The difference is about 1-2% if you use a tire calculator, that means KM reading will be very minimal and no need for any adjustments.

bcbz71 · May 23, 2015

Had the 275 BFG KO2's on for around 2 weeks now, love them. The old KO's might have looked skinny but the new KO2's definitely do not, they are real beefy. Look way better than the stock SRA's.

The tread width of the KO and KO2 is still 9" in 275....do the KO2 have a wider section width? Post up some pics from the rear of your truck. Here's one of an F150 I had with 275/70r18s. Looked great from the side....skinny from the rear.