New Tires Better MPG

[user 62851]

Hello all. I just wanted to make a post and say that I just got a front wheel alignment and 4 brand new Michelin LTX M/S tires on my 04 ST last week. I made the upgrade from the Bridgestone Revos to these. I purchased the same exact size (265/75R16) and I'm getting way better MPG. I have filled up 3 times since getting them and wow! With all the upgrades in performance plus the Revo's, I was getting around 310 MPT and still have about 2.5 gallons of gas left. Now with the LTX's, I'm getting about 380 MPT and still having 2.5 gallons left. I haven't made any changes to the system other than what I ran before. I seem to get better mileage using the XCAL3 with 89. Its pretty good. Not sure what the big difference is between the two, or if its even the tires that is helping. Might have been the front wheel alignment that is helping out the greatest. Just wanted to post and give my results. I'm loving it right now.

 

[EddieS'04]

Tires can make an improovement. But there are too many varibles to judge miles to the tank. I will only do it miles to the gallon.

 

[Woppy V]

oh trust me it's the revos... I went from 400 a tank with the 255 good year's and now with the 265 revos I am only getting 340.



keep in mind that the 255's were when she was bone stock. now I have all the performance mods and am still at 340

 

[JerryW Gilliland]

It's probably a combination of all of it, but I didn't do anything but change my tires and saw a small increase.



I put the Michelin LTX M/S on mine too and really like them. I had them on my Expedition 4x4 before that and noticed a difference in mileage, ride and road noise immediately.

 

[CobraXP]

You will see a difference in the computed MPG's, but it doesn't mean you are going more miles per gallon. Per their respective websites, Michelin LTX M/S is 31.6" in diameter where the Bridgestone is 31.9" in diameter. It is not enough to make up the difference you might be seeing, but it will make up some of the mileage being seen. Even though they are listed as they same size, you actually went to a smaller diameter tire, which will increase the revolutions per mile in comparing the two. This also depends on rim width and what the section width is. Air pressure, the alignment you had, daily temps, etc, etc, can make the difference.



I learned this after running different 18's on the Explorer from winter and summer. The winter tires are Michelin Cross Terrains, where the summer rubber is Hankook RH06 (more of a performance tire). The Michelins aloways looked bigger even though they were listed as the same size. I finally pulled the specs on each and the Hankooks are almost 1/2" shorter than the Michelins at their respective air pressures.











Bridgestone specs: http://www.bridgestonetire.com/tireselector/SizeSpecs_BS_EN.aspx?Product_ID=1055



MIchelin specs: http://www.michelinman.com/tires/light-truck/ltx-ms/97979/

 

[JerryW Gilliland]

I don't have a computer.

I do it the old fashioned way: Miles traveled divided by gallons used.

But I see what you're saying. Good point!

 

[CobraXP]

That is the way I figure mine also, but the variable there is if your speedometer is calibrated correctly for the tire size you have. If you change height without adjusting the speedo calibration, your miles traveled will be different. A shorter tire will produce more miles traveled because it is more revolutions per mile. A taller tire will make you lose revolutions per mile, making it seem like there is less miles per tank. Anytime I change tire height I recalibrate the speedo to match.



I have little books in each of my vehicles I keep the mileage and maintenance in. I write down every tank (I fill up, not just put 'X' amount in) including date, total price, gallons used, mileage, and trip mileage. I've been doing it since I started driving. The Explorer's book has all 190,000 miles of gas written in it... :lol:

 

[JerryW Gilliland]

A true stickler for detail.



That got me thinking about back in the 60's. I was driving a 66 Mustang then and I did the same thing. It was my first car and I was very anal about it. Writing down every penny spent; washing and waxing it ever Sunday, etc.



Gas was 25 cents a gallon then. Now that it's approaching $4 dollars a gallon, I don't write it down at all! Go figure. :lol:

 

[Richard L]

I agree with those above who state that you can not accurately measure your mileage using your fuel gauge. Most Sport Tracs will allow you to put in several mor gallons of gas after the pump has shut off several times. Since you never know how full your tank is unless you fill it to the brim and can see the cas in the filler neck, you never know how much gas is actually in the tank and the gauge is just too inaccurate.



I also agree that new tires and a good alighment can make a noticable improvement in mileage, especially if you have not been checking your tire pressures on the old tires. I had a tire with a slow leak and it would drop pressure to about 12 psi in less than a week. That one tire alone would take about 3-4 MPG off my mileage. When I finally realized what the problem was and got the tire repaired I was amazed at the improved fuel mileage.



A bad or misaligned front end can cause tires to drag and scuff across the pavement which increases fuel consumption, as well as doe the simple fact that the old tires have worn off some tread and are a slightly smaller diameter and must rurn more revolutions to go the same distance. New tires will be slightly larger in diameter, as well as the fact that different brands and models of the same size tires may have a slight difference in their diameter



All of these factors can add up to significant differances in you MPG. The tire pressure was probably the biggest factor, followed to a lesser degree by the alignment and the slightly larger new tires.



...Rich