I was wondering what if any fuel mileage difference you have seen after installing new tires? What to look for when buying new tires for better fuel mileage? TIA
What gas mileage difference + or - have you seen after installing new tires?
- Thread starter tenderloin
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I put Cooper CS5 Ultras on a 2000 Beetle TDI and lost about 5 mpg consistently. So tires can really make a difference for some cars. No changes to the car aside from the tires at that time. While traction was excellent in all weather, the rolling resistance was obviously much higher. That is a big difference, but remember that this was a 50 MPG car to begin with. I imagine the change wouldn't be as drastic in something less efficient.
I have read that tire rubber hardens with age . Giving slightly lower rolling resistance . I am assuming the tires being replaced are older , so , that might change MPG ?
Hermann
Site Donor 2023
Went from OEM mileage type tires to a more trucky tire on a Cute Ute and mileage went down about 8%. (1.5 mpg)
2005 Mariner the new tires were Destination LE's
2005 Mariner the new tires were Destination LE's
I've found that high grip and high rolling resistance tyres really give bad mileage on coarse (new) road surface. On older and smoothed off surfaces the hit is almost non-existent. Drove a longer distaqnce on a new road yesterday and I found the UHP summers gave me a 20% fuel efficiency hit compared to the old road for the 2nd half of the trip. I'm sure grip went up aswell, but who needs that at 80 mph?
Sidewall flex consumes energy. However, don't assume you'll get better fuel economy with stiff high performance tires vs all-season tires.
I highly doubt Jetronic lost that much fuel economy due to tire choice. 30 to 24 MPG as an example doesn't sound right.
I highly doubt Jetronic lost that much fuel economy due to tire choice. 30 to 24 MPG as an example doesn't sound right.
Ah ....... Mmmmm ......... Not exactly.
Ya' see, the stiffness of a tire hardly plays a role in rolling resistance, because that stiffness is small co mpared to the stiffness generated by inflation pressure.
Further, RR is controlled by 3 things:
1) Deflection - and most of the deflection is controlled by the inflation pressure.
2) The amount of material being deflected - which is mostly tread rubber. So as a tire wears out, the RR gets better!
3) The properties of the material being deflected - again, mostly tread rubber. There is a 3 way technology triangle involving treadwear, traction, and RR. Car manufacturers are interested in fuel economy, so they set the tire specs to minimize RR - and they sacrifice treadwear and/or traction to get it.
Of you want to know more: Barry's Tire Tech: Rolling Resistance and Fuel Economy
And just to give some perspective: There can be up to a 60% difference in RR for the same size tire.
And the worse fuel economy jump is going to be taking off worn OE tires (the ones that came on the new car!) and replacing them with long wearing ones.
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I have always experienced lower fuel economy after putting new tires on. Older tires have lost rubber so weigh less most likely, less traction so lower rolling resistance if all else is equal. I should add that worn tires often make a car handle funny. New tires bring life back when you think you might need new suspension tires can often help
I think the main difference is just due to the larger diameter of new tires due to full tread depth. So you are just going further per km indicated compared to the worn out old tires.
I think i remember CapriRacer stating that older tire carcasses actually grow in size.
60 to 50 actually, but only on that section of road, there was no dicernable difference o the older surface. windstill day too