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2012 Sorento, 2000 Boxster, 2002 Pontiac
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Discussion Starter #1
MY 2012 V6 LX (35K miles) with the factory tires averaged 23/town and 27/hwy. Put on a set of Cooper CS4 all seasons 30 days ago. Now the average is 20 and highway best is 23.

Tires cost me around $720, and that's how much extra gas I'll be buying this year. :(
 

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2013 Sorento EX V6 AWD
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There's no way the tire change would make that much difference. Are you SURE they're properly inflated? If they're under-inflated, that could easily cost you a few mpgs.
 

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2011 Kia Sorento I4 FWD 6Spd, 2005 Audi A4 Quattro 1.8T 6Spd
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Some thing to keep in mind:
1. We are now using the "winter" formulation for gas. I saw a 2-3 MPG drop with my I4.
2. You will see a drop in MPG when replacing the OEM tires. They are optimized for low rolling resistance. This is evidenced by the complaints in this forum about traction.

Both of the above combined will account for your MPG drop...
 

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Cerato S Hatch Auto
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Aren't Cooper tyres the ones "with the extra tread depth"? That may make a difference to the overall diameter. Probably also decreases economy due to tread "squirming".

According to a Cooper site, overall diameters are the same as nominal OD calculated from the dimensions, but this may not be the case in practice. Anyhow, check your odometer for accuracy; you might be going further than you think on each gallon of petrol.

Michelin XM1 and XM2 tyres are promoted as fuel-savers, and I have found this to be true. It is claimed that the tyres will pay for themselves in fuel savings over their life, and this is fairly close to the mark (depending on the price of petrol). 40 MPG vs. 37 MPG (Imp.)
 

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2012 Sorento, 2000 Boxster, 2002 Pontiac
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Discussion Starter #5
Found a couple reviews where people complain about a substantial mpg loss with these tires. Can't say for sure about the winter gas, as I noticed the drop within days, most likely with the same gas run with the old tires.

However, I'm happy with the snow/slush performance of the tire. Dry road handling is great, and while I didn't notice them being super quiet, they're certainly no noisier than the OEM tires.

Cooper CS4 (T-rated) Gas Mileage
Cooper CS4 Touring information from Consumer Reports
 

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Cerato S Hatch Auto
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Found a couple reviews where people complain about a substantial mpg loss with these tires. Can't say for sure about the winter gas, as I noticed the drop within days, most likely with the same gas run with the old tires.
The MPG figures in these reviews don't seem reliable. One claimed 20% penalty with Coopers, the other suggested better economy after a running-in period, but only on the basis of a couple of tests.

I still think you should check your odometer. A bit late to check with the old tyres, but at least you could get an accurate figure for the Coopers for future reference.

Check odometer against GPS or over a known distance. We have calibrated 5 km stretches on some highways where you can do this, although with digital odometers, you have to estimate the second decimal (±0.1 isn't precise enough). Alternatively, our road signs are accurate to ±1 km over longer distances (e.g. 500 km) and agree with GPS and the Google Maps "Get Directions" application. I also have a "local lap" which is 5.31 km, and this provides a quick check for new cars or new tyres.
 

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2012 Sorento, 2000 Boxster, 2002 Pontiac
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Discussion Starter #7
Well it's May and the Cooper tires have about 6000 miles on them.
Since the weather has warmed this spring my mileage has gradually returned to 24/town and 26-27 /hwy. I've heard stories of tires needing a break in to scuff off the soft layer, or maybe it was a combination of cold driving/winter gas/new tires.
Anyway...strange mpg dip over the winter months and now back to normal.

Tom
 

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2013 Sorento EX V6 AWD
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Well it's May and the Cooper tires have about 6000 miles on them.
Since the weather has warmed this spring my mileage has gradually returned to 24/town and 26-27 /hwy. I've heard stories of tires needing a break in to scuff off the soft layer, or maybe it was a combination of cold driving/winter gas/new tires.
Anyway...strange mpg dip over the winter months and now back to normal.

Tom
10%-ish reduction in gas mileage with winter gas is pretty much bog standard.

You may thank your local Archer Daniels Midland lobbyist. :)
 

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2015 Sorento EX V6 AWD Ebony Black
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I noticed the same thing with the new Cooper CS-4's on my Sportage. Initially it seemed like I had a mileage loss, but now it's Spring, and after over 5000k miles it is back to where it was originally. This is my 3rd set of these, on as many cars, and I just love the extra all-weather traction, & smooth, quiet ride. They're not really snow tires, but do better in snow then any other all-season tire I've had.
 

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2011 Sorento V6 AWD
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Well it's May and the Cooper tires have about 6000 miles on them.
Since the weather has warmed this spring my mileage has gradually returned to 24/town and 26-27 /hwy. I've heard stories of tires needing a break in to scuff off the soft layer, or maybe it was a combination of cold driving/winter gas/new tires.
Anyway...strange mpg dip over the winter months and now back to normal.

Tom
Its not strange someone already told you. We see serious decrease in mpg during colder weather due to the winter fuel formula and cold weather affecting fuel mpg. Mine always goes down 1-2 mpg but I get it back come spring. I run new Firestone Le2 tires way more traction and tread but it did cost a little in fuel economy but the traction off road and in winter/wet conditions doesn't even compare with the stock junk tires they had on there.
 

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2013 Kia Sorento EX FWD v6
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I too had bought new Cooper tires for my Altima two years ago and the miliage dropped substantially. I was very upset at the time. My son now has the car and the miliage is back to normal. I guess the tread wore down a little. Is this normal for all new tires?
 

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1985 Subaru Loyale (wagon), 2000 Kia Sephia (sedan), and 1969 Mercury Comet (coupé)
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A simple question

Very kindly, let me ask: Did you used the same tire size?

in example, if the old tires were 235 / 60 R 16 ... Are the new tires of same numbers?

Kind Regards.
 

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2013 Sorento, Suzuki V-Strom
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New tires with deep tread always have higher rolling resistance than old tires with shallow remaining tread.

New tires have a larger outside diameter than worn tires--the difference of the worn-off tread depth. This causes the new tires to turn fewer revolutions per mile, and your odometer doesn't read as many miles for the same run, thus fewer recorded miles per gallon, not always fewer actual miles per gallon.

Different brands of new tires of the same listed tire size can have different actual outside diameters.

http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=177

There is always a 3-way trade off with tire characteristics: traction, rolling resistance, tread life. Increase one and you'll decrease one or two others. OEM tires are spec'ed to give low rolling resistance, i.e., good gas mileage, as well as a comfy ride on the test drive. Frequently the traction is poor and the life may be short. Get better traction and give up tread life and/or gas mileage. You get the idea.

Cooper has replaced their CS4 with the CS5. It has a 17" size that fits our cars, but not 18" In both 17" & 18" Cooper offers their Discoverer CTS.
"The Discoverer CTS is a premium luxury touring tire designed to deliver higher levels of wet traction, ride comfort and appearance. The CTS provides enhanced ride comfort and performance for your high-end SUV, CUV or truck."
 
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