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Author Topic: How many L/100KM do you lose from your winter tires? Back to Topics
kevinf28

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Hamilton

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Message Posted: Dec 28, 2012 9:19:29 AM

Hello all,

Just curious, since I put on my winter tires, I went from a 7.8L/100KM average to 8.3L/100KM, I do a lot of country highway + 401.

I did not buy specialty winter tires for "low rolling resistance" as I thought that was counter productive.

How many L/100KM do you lose from your winter tires?
REPLIES (newest first) Post a Reply
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IAMCANADIAN73
Champion Author Ontario

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Message Posted: Mar 20, 2013 12:02:35 AM

1-2
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golfer7332
Sophomore Author Toronto

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Message Posted: Mar 19, 2013 10:54:58 PM

The colder temperature drops gas mileage. I didn't find snow tires uses more gas. For the last few months the initial idle usage is 1.3-1.7 l/hr in the cold morning with the tdi which increase the average to 6.-6.3 l/100k
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giwan
Champion Author Michigan

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Message Posted: Mar 16, 2013 12:56:09 AM

how sure are you of calcs
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chipote
Champion Author Washington

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Message Posted: Mar 15, 2013 11:52:30 PM

Did not loose any mileage
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Banjoe
Champion Author Winnipeg

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Message Posted: Mar 15, 2013 8:15:26 AM

Not sure that I lose anything with the tire change but the temperature change is a big downer for mileage in our diesel. Consumption reads very high until the little creature finally warms up. Until then, it's pretty brutal.
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Dennis783
Champion Author Des Moines

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Message Posted: Mar 15, 2013 8:06:06 AM

I use the same tires all year
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sagnat
Champion Author Riverside

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Message Posted: Mar 14, 2013 2:46:16 PM

Fortunately I live where I don't have to use snows. I did live and work in Michigan for a couple years and ran Bridgestone Blizzacks on my Mercedes in the winter. Didn't really notice an impact to the MPG but then again that big 5.6 litre engine didn't really get good MPG anytime.
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metalhat73
Champion Author Wilmington

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Message Posted: Mar 13, 2013 10:46:59 AM

Used Nitto SN2 snow tires this winter and didn't see a reduction in fuel consumption. The reduced speed may had helped.
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PaylessKY
Champion Author Kentucky

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Message Posted: Mar 13, 2013 12:51:47 AM

I use the same tires all year long.
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herbiepopnecker
Champion Author British Columbia

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Message Posted: Mar 12, 2013 10:36:01 PM

I get better mileage - mainly because of reduced speeds.
I wonder if because you're pushing tons of slush and snow out of the way its fair to blame the mileage drop on the tires.
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pmjwright2
All-Star Author British Columbia

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Message Posted: Mar 12, 2013 2:26:32 PM

Oh, and driving habits too--people likely don't drive as aggressively on those days when traction and visibility are poorer. Much more common in winter!
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pmjwright2
All-Star Author British Columbia

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Message Posted: Mar 12, 2013 2:13:07 PM

Kevin, I also lose about 0.6 l/100 km. (6.5 summer/7.1 winter on my commute). Part of that is the switchover to winter gas, but that happens around Oct 1 and April 1 and I can see the change in fuel consumption even when I haven't switched tires over.

We all know that winter FE is affected by severel factors: softer grippier tires with higher rolling resistance; colder denser air (more wind resistance); winter vs summer gas (3% less energy per litre according to PetroCanada); increased rolling resistance caused by snow or water on the road; longer warmup time (even if you just start your car and go) where your engine is running inefficiently. About the only factor that works the other way is using A/C in summer.

But here's another factor that is rarely recognized: the difference in tire diameters. Over many years and vehicles and tires, I've found that snowtires are usually slightly smaller in circumference than the equivalent all-seasons. With my current car, I've noticed my commute is exactly 1 km (2%) shorter in summer vs winter. No, my office did't pick up and move, it's the exact same route!

Just because of the difference in tire circumference, my odom under-reports the summertime distance relative to winter because the slightly taller summer tires will make fewer rotations on the trip.

As a result, the difference in FE is even greater than I have calculated above.
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dontuknowOH
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Message Posted: Feb 10, 2013 8:42:05 AM

If one really thinks about what the differience is between a rough tread traction tire compared to a smoother surface softer compound regular road multi purpose,quietier tire,then those differiences may show the loss % in mileage.

My thoughts are the traction tire has more large sype areas rather tread tunnels to trap material into the tread forming a grip on the substance snow/mud/whatever.

The rough design tread catches air on dry days each rugged rubber traction part acts like a mini fan blade on the outer wheel surface acting somewhat like a blower fan when turning fast at highway speeds,fanning tha air.

Also all the tires I have looked at had rough design edge iregulatories for deep muck travel,desiged to get a grip from the tread sidewall.these finned areas catch air also and the rolling resistance could be affected (increased).

A few drivers have seen furnace blower cage fans,they have small finns but do move a lot of air,need HP energy and the rotor fan spins normally slower than an auto wheel,that's my comparison or reasoning for the fuel energy loss,possible the Winter traction tire is physically heavier weight wise,that affects motion dynamics. Just my thoughts....
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HotRod10
Champion Author Wyoming

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Message Posted: Feb 5, 2013 11:22:17 AM

Some of your loss could be due to the engine taking longer to warm up, winter blend fuel, and other factors of winter driving, and not just the tires. Even so, a 6% decrease in mileage to decrease your stopping distance on snow and ice by 20% (over all-season tires) or 125% (over performance/summer tires) seems like a worthwhile trade to me. Tire Test

I actually went to the junkyard a got an extra set of rims for my car so I don't have to pay for mounting and unmounting the tires twice a year.

[Edited by: HotRod10 at 2/5/2013 11:26:08 AM EST]
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kevinf28
Veteran Author Hamilton

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Message Posted: Jan 1, 2013 7:40:14 PM

My average actually got better.. now its sitting at 8.1L/100KM. I have only had this car two winters, and I don't have last years written down... at least now I do for next year ;)
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Banjoe
Champion Author Winnipeg

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Message Posted: Jan 1, 2013 6:56:10 AM

golfer7332 - thanks for those numbers. Our TDI is seeing the same drop with the winter temps.

Our drop doesn't' come from excessive idling as there's very little time spent trying to warm things up as these critters never seem to get warm just idling.

I was thinking there is some change in diesel fuel blends in the winter as there are with gasoline but don't know if that's the case or not.

The cold air is nice and dense so the engine should be running a bit more efficiently.

Maybe all the winter clothes as well as the collected ice and snow that adds enough weight to consume more fuel?

Long story short - mileage drops when the thermometer drops.
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DanFMA
Champion Author Massachusetts

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Message Posted: Jan 1, 2013 6:23:54 AM

Don't change tires.
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golfer7332
Sophomore Author Toronto

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Message Posted: Dec 31, 2012 9:56:21 PM

It could be a number of factors. A longer idle warm up time. More ethanol in winter gas has less energy per volume.
My TDI diesel has shown typical idle fuel use is .9-1.1L/hr. In summer, it is .6-.7L/hr. The average 50km trip has jumped from 5.2L/100 to 5.7-5.8 in the winter months. this was before the snow hits.
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OceanArcher
Champion Author Mississippi

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Message Posted: Dec 31, 2012 11:03:36 AM

Losing grip/traction with the road under slippery conditions is not a good thing -- it leads to unplanned visits with the ditches alongside the road ...
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MertieMan
Champion Author Lexington

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Message Posted: Dec 31, 2012 8:09:54 AM

I wouldn't know because we don't especially use winter type tires in this area.
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kevinf28
Veteran Author Hamilton

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Message Posted: Dec 30, 2012 9:54:50 PM

I get the lower fuel economy with or without snow. Im sure with slippery conditions it would be worse though, as not all engine force is translated into forward momentum.
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OceanArcher
Champion Author Mississippi

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Message Posted: Dec 28, 2012 10:23:32 AM

I would think that you may be looking at the function of snow depth --> the deeper the snow, the harder it is to make headway.
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