10 lbs, per tire lighter and no better MPG,,wtf..

as the title says,, just went from a 265/70/17 nitto ridge grappler E-load 54 lbs, to a 265/70/17 general grabber-at-x, 43 lbs. standard load..and see no improvement in MPG, possibly less after 3 tanks of gas.. wtf

 

Have you considered adding a wing to your bed?

 

Are they inflated properly? Did you calculate it or are you going off the computer?

 

same experience, went from an E to a C in the same tire, same size and only gained maybe 1 mpg. Its really the tread pattern and size that effects mpg more than the weight.

 

Interesting. But maybe give it a few tanks to see more average

 

you cut 44lbs off of a truck that weighs ~4500 lbs. that's like less than a 1% weight reduction. Happy friday i guess.

 

Great question. OP read this.

 

44lbs rolling should make a difference. I'm guessing it's the computer that's reading wrong. Not a true calculation.

 

Has to do with rotational mass, not necessary overall weight loss in comparison to the whole truck.

 

There was another thread like this recently. What I was trying to get in the post below is that even if your tires were 100lbs each, it's really not much.

 

Probably because the tires were installed right around the time winter gas was switched over. That and the mental mindset behind really driving it to see how sticky the new tires are.

 

still a small change. what does the rim weigh. 25lbs??? just guessing.. so 12.6% reduction in rotating mass. i wouldn't expect much of a change unless he changed his aero package

 

Soo....whats the actual MPG difference?

 

40lbs means nothing. Come on guys. If we went by that premise. Every time you put you 100lb wife in for a road trip your mileage should go to crap. 40lbs means nothing.

 

That’s a bad comparison because the wife isn’t unsprung rotational weight

 

I know everyone talks about rotational weight, it makes a difference at get up to speed but once rolling mass is moving it keeps it inertia much easier, it harder to slow down but at speed it wants to keep moving so it actually helps. But all in all 40lbs isnt magically giving you 2-4mpg.

 

Try two experiments.

First pick your wife up, hold for one minute and then put her down.

Next, pick her up and spin her at 500 RPMs for one minute. Then stop and put her down.

Are these the same thing? Which one is harder.

 

Not yet

 

40 lbs. of unsprung weight is not the same as 40 lbs. cargo. Try running with heavy boots then try running with track shoes, more energy would be expended with the boots.

 

Driving a 4banger, I can tell you that it has a harder time keeping those damn things rolling. The road isn’t a perfect frictionless physics homework problem. The road has small hills and turns all which cause continuous acceleration.