wayoflife

exactly. it makes no sense to obsess over something as trivial as 10 lbs. extra per tire when there is so much more you really need to be looking at. when building up your jeep, you really need to step back and look at the whole picture.

of course, you're talking to a guy who runs 40x15.50 toyo's mounted on 20" atx slab wheels that have a combined weight of 187 lbs a piece. of course, this is to say nothing about how heavy the dynatrac prorock 60s they're mounted to weighs and yes, my jeep is a daily driver.

dognights

I remember filling the tires of an old trail buggy about half way with water before going out with it when I was younger.

Sure like anything else weight matters. I dont personally think it makes enough difference for myself to choose a tire like the KM2s thou over something less likely to tear a sidewall. If you really are concerned about improving mpg and want to save a little weight use a narrower tire. Im personally a fan of narrower tires anyway, because of how weight is applied. Unless the only thing you do is run around in soft sand or super deep mud, most of the time I would say you would be better served with a narrower tire anyway.

The little weight you save on the tire plus a little less weight for the rim and there is your ten pounds you were looking for. Also less rolling resistance as mentioned above.

wayoflife

LOL!! old school tech great unsprung weight for trail use but nothing i would recommend for the highway.

maybe it's because of where you live and the kind of trails you run but, a nice wide tire actually kicks butt on the rocks as it gives you a much greater footprint and by virtue of it, superior traction and stability.

RedRockJeeper

you got balls Roll I would never and will not run 37's on my D30. I love being underneath my Jeep adding stuff at home, I DO NOT like being underneath my Jeep fixing something on the trail, lol!!!!

TheTerminator

I was simply giving an extreme example for the sake of getting my point across. 10 lbs per tire probably won't be a deal breaker on a JK. But if you're going to double the stock tire weight, I'm sure the Jeep and your pocket will feel it. So tire weight does matter.

TheTerminator

Everyone needs to decide for himself where he wants to compromise and how much. There is nothing wrong with trying to achieve a bit better gas mileage where possible. Those extra 1-2 mpg can easily turn into $50-$100 or more savings per month.

wayoflife

since you seem to have missed it, that's what we're talking about here. the op is NOT trying to compare stock tires to tires that are double their weight but rather, he's asking about two tires that are both the same size and one of which weighs about 10 lbs more. contrary to what you were trying to suggest before, this WILL NOT be a deal breaker.

wayoflife

please, i never said that there was anything wrong with trying to achieve a bit better gas mileage, only that you're kidding yourself if you really think that 10 extra lbs per tire weight savings is really going make a difference. hell, you might as well not have any passengers ride along in your jeep as that would compromise your mpg as much as 2 gal or more per person. of course, you can believe whatever it is you want to believe especially if it helps you to sleep better at night.

oleskool

Ahhh the ole mass moment of inertia issue. In my world this really matters but on a 5 thousand lb jeep and extra 40 lbs of rotating mass should never be noticed. They might take a fraction more torque to turn over but once moving they tend to want to stay moving so what ever you lose which is an extremely tiny percentage is gained when you let off the gas and coast. Yes this might be seen more in stop and go driving but dropping mpgs shouldn't be the case. I drive a 6 speed so I have a little more control on my gearing but I didn't see a 2 mpg drop pulling my 8 ft trailer with 500 lbs of gear on it. I was still pulling 17 mpgs on 35's with stock Rubi 4.10's.

jkrubcon

Some one earlier in the thread was talking about unsprung weight. It reminded me in the late 70's when everything was stiff leaf suspension and the higher the better. The jeeps I was wheeling with(at that time I was wheeling Broncos) had some kind of fluid in their tires to keep the rubber on the rocks. Seemed to work good. No one cared about mileage back then like today. Sorry about the off topic thoughts .