[drescape08]

well i bought an 08 escape that came with the horrid silver painted steel wheels. (which are for sale for whoever wants..hint hint) so i upgraded to some nice 18" chrome wheels that came with 235-65/18 tires, which i know is one size bigger and shouldve got 235-60 to make them stock size...but those came w/ the wheels. anyways they have hurt my gas mileage and i do add in the 3.7% tire size difference. i found some 255-55/18 which is the same size tire as stock diameter size but are wider. would these help my mileage or am i just not gonna get the same size i upgraded wheels? any help?

 

[stone]

Not sure about that.

 

[PollKat]

...... anyways they have hurt my gas mileage and i do add in the 3.7% tire size difference. i found some 255-55/18 which is the same size tire as stock diameter size but are wider. would these help my mileage or am i just not gonna get the same size i upgraded wheels? any help?

Seems the wider tire would hurt mpk/mpg. More area contact (tire) with road. But from all I've listened/read tires make little difference in mpk/mpg if any. They have nothing to do with Air/fuel ratio (volumetric efficiency) timing, spark, etc. etc. If your millage went down and you took into account the difference.(tire size) Then something else is wrong. Case in point. I did allot of research on the Goodyear Triple Treads that I had installed. Some complained, that there mpg went down. So, on goes the scan-gauge. On my "02" there was zero difference in mpg. So I just concluded that they were driving a bit more aggressively..

 

[Scooter Scott]

Here is what your current setup looks like:

 

[drescape08]

i didnt think it wouldve affected it either...yeah these are bigger rims...but also aluminum and not steel..so not too much weight gain...and if anything i should get better on the highway...a lil bigger equals less resistance touching the road and a lil bigger means you go just a touch faster w/o the rpms. so i dont know. i changed the fuel filter and usually run 89 octane. so i dont know. and that picture is the same site i found out what my tire size was and how i account for the difference in mileage

 

[Squishy]

How much has it affected your mileage, and could you be driving more aggressively with nicer wheels and tires? I go one inch taller for my winter tires (5.4% difference) and my mileage is pretty much the same after I account for the size difference. I also go from aluminium* wheels in the summer to black steelies in the winter. My mileage does drop once it gets cold, but that would be because of longer engine warm-ups.

You can try some used tires in the correct size (thinner, O.E. diameter) to see if your mileage improves. Those should be around $20-$30 each.

*Scottie, you saw nothing. :tease:

 

[jonas1022]

About the worst thing with a wider tire is you get more bump steer. It used to be that wider tires would produce lower MPG. But that is not so much the case any longer...

 

[drescape08]

well i really dont want to just buy tires to check...since i have to have the tpms sensors reset as well. i got 33 mpg driving it home on a very hilly road running 65-75 the whole way and drove to gatlinburg and around and still maintained 29mpg. but i drove to IN from KY with cruise set on 80 and no gunning it at all and got 25 mpg. which was the same driving style when i went to gatlinburg and i drove through the towns there and used windows this time and no a/c or windows down goin to IN. which there wasnt the hills??? should this tire and wheel combo have hurt it that bad? and so i guess the 255/55 wouldnt help?

 

[jonas1022]

Maybe your pushing it outside it's engineered box for best mpg? IDK.

It's best to check fuel mileage over a period of time, filling at the same gas pump, parked in the same spot, with the same ambient air temp. Sheesh! I never did. Just averaged the fills over a period of time. One tank is not necessarily representative of what your Escape is getting. For the 25 mpg, it could have been crappy gas... :shrug:

 

[drescape08]

im just goin off of the way i drove before to now and it wasnt any different. ill watch it for a while and see how it goes. by the way...what octane gas does everyone use. ive been using 89 most of the time. have used 87 though and did on my long trip. didnt know if that mattered or not but i do only use like shell, bp, marathon gas.

 

[Scooter Scott]

I use 93 but I also have the XCal 2 that tunes my Escape for the 93 octane.

 

[jonas1022]

87 octane in everything. That's what the factory recommends. Any higher octane, and your wasting money.

Unless you use your XCal to program your Escape differently!

 

[drescape08]

so im still continuously getting around 24-26mpg instead of 29-31mpg. i even added a k&n. could it be the tires i have are a stickier rubber? i just dont understand how i dropped that much on a 3.7% bigger tire. this means im doing 62.2 at 60mph i wouldve thought on the highway it wouldve been better w/ this. but its not.

 

[Putt]

First I would max out the air pressure in the tires, look on the side and see what the max pressure is and put it at that. Don't worry about the air getting hot and going over pressure, if the air is getting that hot the tire is already shot. Then I would watch the milage over a period of time, remember cold air is dense and gives better combustion, as does altitude, and humidity. While the wider tire does have a bigger foot print it may or may not have more rolling resistance than your old combo, up the air pressure to decrease rolling resistance. And you may have step over the edge of the "sweet spot" for your particular engines HP/torque range.

If the vehicle is setting higher you might be experiancing some under cariage air drag issue, try a lower front bumper airdam.

Be sure you are not comparing non E gas and E gas figures, ethanol will drop the MPG becuase it is lower in btu' than gasoline.

Let us know what you come up with.

PUTT

 

[Davis137]

Go and get your tires filled with Nitrogen...

This is going to be expensive, but your tires won't expand or contract with gas in them.

L8tz

 

[Squishy]

What? Yes it will. ALL gasses will expand when heated. What you're referring to is the fact that compressed nitrogen used in racing applications is "dry", so water does not enter the tires and does not drastically affect pressure when it heats up and becomes steam. Most tire shops that offer nitrogen inflation use a compressor fitted with a "filter" that separates N2 gas - I have no idea if it really does come out "dry". The Escape can not get up to a speed where nitrogen will be of benefit.

The only (barely) plausible benefit of nitrogen is that it may effuse slower than oxygen, and even then, air is already 78% nitrogen. Also, Graham's Law states that molecules with lower atomic mass will effuse at a greater rate than molecules of higher atomic mass - nitrogen gas, N2, has an atomic mass of 28 g/mol, compared to O2's 32 g/mol. That is the complete opposite of what nitrogen marketing says. Who to believe?

If your tire shop does this for free, then go nuts. But paying for it? :doh:

 

[jonas1022]

What? But paying for it? :doh:

Right! Don't pay for it, I never do... :blush:

 

[drescape08]

well i already had nitrogen in them...and i upped the tire pressure from 32-40psi. and it still hasnt seemed to do anything for my mileage. its also cold as balls here...so im guessing thats hurting my mileage as well. looking for an xcal3 to see if i can get some back that way.

 

[Scooter Scott]

make sure to contact Torrie at [email protected] as he is our local SCT dealer and a member of this board.