Tire ? - AT/KO vs KM2/MT and fuel mileage

[doug720]

I was looking at the BFG website comparing the AT/KO and KM2/MT tires and noticed a comparison for fuel economy. It shows the KM2/MT has more rolling resistance than the KO/AT tire. The 0 - 10 scale shows the KO/AT with a 6 and the KM2/MT with a 4!

That is equal to a 20% drop in fuel "Efficiency" per BFG! Pretty big IMHO!

My question, has anyone switched from KO's to KM2's and noticed a big drop in fuel mileage? If yes. I hope it was not 20%? What has been some real world experiences between these 2 tires?

I am getting a set of taller tires for a little more rubber overdrive, but saw this and was concerned. I'm not a hardcore off roader, but lots of dirt roads, rocks and sand, but with a little snow too (I have good chains so KM2 are OK).

Thanks

Doug

 

[lehiguy]

The idiots at BFG deemed it prudent to only manufacture a particular type of tire once a year if that. I have been waiting for nine months for a 35x12.5r15 KO. The KM2s are on eternal backorder as well. For that reason, I suggest you look for a brand that is actually available.

 

[lovetoski]

All other things being equal, MT's will flex more, generate more heat/noise, wind-drag is higher, which means that they require more energy to roll down the road...ie, lower fuel economy. Can't say whether it's 20% or not. I went from 33X9.50 AT's to 33X10.50 MT's and my fuel milage went down by 1 - 2 mpg.

 

[doug720]

That's the info I was looking for. BFG has the KO's back ordered until at least early August, but the KM2's are available now which is my dilemma!

I don't DD my 60, and only drive around 4-5000 miles a year, but 1-2 mpg is still a lot.

I use 33X10.50X15's, so the choice is somewhat limited...Bummer!

I was going to pick up a set of KM2's Wednesday, now not so sure.

Doug

 

[lovetoski]

I went to MT's because I wanted the additional traction for off-highway adventures. If you don't need the additional traction, then I'd stick to the AT's...better fuel milage, tires will last longer, and road noise will be reduced.

Also, keep in mind the dollar cost of lower milage is not that painful when you don't drive the truck that much. 5000 miles per year at 15mpg (highway) versus 13mpg = 50 gallons if you see a 2mpg difference.

 

[doug720]

KM2's go on tomorrow!

Final straw was when I spoke to BFG today in North Carolina...They said; "The start of production for BFG KO models will not begin until the second week of August. From that point it will take 3 - 4 weeks for distribution to reach regional centers and 1 -2 weeks to hit dealers! Basically sometime in September!

Could not wait that long as vacation and travel time is nearly here.

Lets see how I like the KM2's...

Doug

 

[FJ60Seth]

Run your tires at the maximum pressure that provides a good wear pattern. I run my KM2's at 36 psi and I get 12-13 mpg driving 55-60 mph on a flat freeway.

 

[doug720]

Hopefully the diesel helps somewhat, maybe only a drop down to 18 mpg +/-?

Doug

 

[doug720]

Well, the KM2's are on on and so far, I'm very pleased! They are quiet, ride well, smooth and the 60 drives perfect.

I found something interesting, I compared the new 33X10.50X15 KM2's to my old KO's of the same size with both mounted and aired up, and the KM2's are taller by over 1.25 inches. Yes the KO's were partially worn, but had at least 75% tread left. Plus, I pulled my brand new 33X9.50X15 KO spare and it was nearly the same difference.

The extra diameter helps with a little more "Rubber Overdrive". More good.

Hope the KM2's continue this way. First road trip in a couple of weeks will confirm how the fuel mileage works out.

Plus, and this sounds hind of poser-ish... They do look good on a 60! Dammmmm good!

Doug

 

[klinetime574]

That's really interesting. My KO's are starting to look small to my eye. I may have to reconsider tire choices for the future.

You gotta post a picture btw...

 

[lehiguy]

By the time these morons get around to making more KOs, I will have been waiting a year for two 35x12.5 15s. I am going with a different brand because BFG pissed me off.

 

[doug720]

YA, YA...All BS without pictures!

Here you go.

Doug

 

[lovetoski]

booyah!

 

[rustybucket]

look nice just hope you are seen when on the road in a dark and raining night

 

[doug720]

look nice just hope you are seen when on the road in a dark and raining night

We don't have those types of days in SoCal! Never rains and way too many street lights.

Just kidding, thanks.

Doug

 

[gregnash]

Looks real good with the MT's doug! Can't wait to see mine in my driveway (who knows when that will be though).

Question, what roof rack is that?

 

[orangefj45]

Everytime somebody mentions fuel economy and land cruiser in the same sentence, I have to laugh.

Never gets old.


Georg

 

[doug720]

Looks real good with the MT's doug! Can't wait to see mine in my driveway (who knows when that will be though).

Question, what roof rack is that?

I made the roof rack.

Jorge, come on, all us cruiser owners are trying to save the planet too!

Doug