To sipe or not to sipe KM2s?


2005 Expedition Trophy Champion
Would you sipe KM2s? I'm a proponent of siping but I don't agree that it extends the mileage of the tire. What say you?


I took my KM2's out in the snow last year, is was packed a little, but it did 4 wheel slides really easy. If I lived where there was more snow, I'd sipe them.


Well, I run a set of them on my rig, and while they are great tires for off roading they scare the ever living heck out of me to drive in the snow. This could partially be do to the size I am running, 35, 12.5, 16's. I have had sipped tires in the past and I really do think it helps in the wet/frozen,snowy drives. I would say yes, it's very worth it and can't really do anything negative to your rig. IMHO. :)



Expedition Leader
The idea that sipes help dissipate life robbing heat from the tread forms a compelling argument as to their benefit. Added traction in snow and on ice is another. I'm a siper!


Active member
I think the decision to sipe or not to sipe depends more on the conditions on which the tire will be in service..........depends on where you live, weather and the terrain you drive on the most and your driving habits.

Although I have no experience with the new BFG KM2's I have siped tires in the past and had mixed results. Some tires it made better (hard rubber compound) it caused a bunch of "chunking" of the tread.(really soft compound) Where I live now I travel nearly exclusively on gravel roads and I don't see siping being advantageous on the terrain I travel on, in fact I see all those biting edges as a point where the tread can chunk.


I'm running the same tyres as well. Although I have 37's (knobs the size of a rubics cube) with a detroit locker rear end and so the tyre chunking is happening without them being siped. I do plan on sipping the front tyres though. Good braking on an icy mountain road with 10,000' cliffs is nice to have. Dont forget the weight of your rig is most important variable. I have a 100gal diesel transfer tank that works wonders!

I'm going to start out with a 2.5-3mm cut and work from there once I reach the Andes this summer (our winter). This also means I will be sipping them once every couple of weeks if I will be doing 200-500 miles days each day.

A pro Colorado rock crawler told me this... "Sipe only the two middle treads! Not the outside ones!"


Viking with a Hammer
Yeah, sipe the center lugs. I don't see any disadvantage to doing so.

I think I'm going to use a set of GY Duratracs for the winter instead.


Expedition Leader
Lot's of snow driving sipe them. Or if you do lot's of rock crawling. Otherwise do not sipe.

my 2cents


FWIW, 2 weekends ago I noticed Bill Burke has the 2 center rows siped on his KM2s. IIRC, he lives in Colorado snow country.



i ran 35 /12.50 /16 bfg mudders ,on my f250 when i lived in bend ,OR ..they are just plan scary with out siping ,after siping the best snow tire i have used .i run dura tracs here in texas as most tire shops dont do siping ..i did the entire tire and yes over time did get some chunks ripped out ,nothing bad .as for the life of the tire ?bfgs are great tires and last long ..hope this helps..


...wait...I don't see the centers siped in that picture?
yeah, it's hard to see and that's not really my picture (just for illustrative purposes, I guess). but he does have the center 2 rows of tread siped and recommended it on the KM2's for any kind of winter driving at his class at NW SarCon (Mt Hood, OR)