So I have been using the Montereys with Continental True Contact for ~70,000 miles. My mileage has averaged 40-48 mpg roughly through 69,000 miles of highway driving depending if my indicated speed was 70 or higher. I switched to 17" Long Beachs with Continental Pure Contacts and it took me to 36-38 mpg on my normal trip. When I had the Arriettas installed with Extreme Contact DWS I average 39-42mpg on the same trip. Maybe it has something to do with possible winter diesel but I am not sure how far South winter diesel is this year do to the colder temperatures. I may swap back to the Arriettas eventually to see the larger than expected loss is do to the Long Beaches or something else.
Fuel Economy Loss after Wheel and Tire Swap
- Thread starter cbman18j
- Start date
Both the Long Beach and the Arriettas are being run with 225/45/17s; the arriettas had extreme dws in that size
jettawreck
Top Post Dawg
Tread depth also causes mileage change, new/deeper tread causes more resistance. Also larger overall diameter decreases the indicated miles, which doesn't change your "real life" mpg much, but does change the calculation results since it tallies up fewer miles on the odometer. Slight changes seem to multiply the results more than expected.
New tires have always returned less mpg than the worn out ones when I have replaced.
Heavier wheels are also supposedly a bit worse for mileage, especially for those doing more stop/go driving.
New tires have always returned less mpg than the worn out ones when I have replaced.
Heavier wheels are also supposedly a bit worse for mileage, especially for those doing more stop/go driving.
Yeah I was expecting some loss from switch from the Avus but compared to the artist has I was surprised by the loss
That makes sense because when I ran the arriettas the tires were not new, they were probably about 25-50% life left in them.
Fixmy59bug
Veteran Member
It can be quite the drastic change...
You are going from a 35lb wheel and tire combination (Avus weighs 17lbs, 195/65-15 TrueContact tire weighs 18lbs)
And you are installing a 47lb wheel and tire combination (Arietta weighs 25lbs, and 225/45-17 PureContact weighs 22lbs).
Not to mention the additional drag of a 195mm wide tire compared to a 225mm wide tire.
2015vwgolfdiesel
Top Post Dawg
$.02
....in general wheel tire swapping (IMO) is going to hurt your MPG.
... In general auto manufactures are pushed hard to get the best MPG results the day the car hits the rode.
... Respectfully your "style" changes are going to negatively affect MPG.
....in general wheel tire swapping (IMO) is going to hurt your MPG.
... In general auto manufactures are pushed hard to get the best MPG results the day the car hits the rode.
... Respectfully your "style" changes are going to negatively affect MPG.
I had expected some negative affects on MPG due to my experience with the Arrietta and DWS combo previously, I was just shocked that there was more negative affects when I went to the Long Beach and Truecontact combo. I would have expected similar results between the Long Beach and Arrietta since the both tires were the same size 225-45/17.....in general wheel tire swapping (IMO) is going to hurt your MPG.
... In general auto manufactures are pushed hard to get the best MPG results the day the car hits the rode.
... Respectfully your "style" changes are going to negatively affect MPG.
turbovan+tdi
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Long beach wheels are pretty heavy.
Andyinchville1
Veteran Member
FWIW - I went from factory Steelies and Ecopia tires (195 65 r 15 ) to
factory Avus wheels and Ecopica in the 205 70 r 15 size and have achieved the same or better MPG's (in addition to lower engine RPMs).
The weight of the wheel assemblies more or less remained the same based on my weight scale (I lost the actual papers I wrote the info on) BUT the avus wheel lightness offset the larger tires weight.
I like the reduced RPM's at speed , increased (slightly) ground clearance, and the look of the more "filled" wheel wells.
Andrew
factory Avus wheels and Ecopica in the 205 70 r 15 size and have achieved the same or better MPG's (in addition to lower engine RPMs).
The weight of the wheel assemblies more or less remained the same based on my weight scale (I lost the actual papers I wrote the info on) BUT the avus wheel lightness offset the larger tires weight.
I like the reduced RPM's at speed , increased (slightly) ground clearance, and the look of the more "filled" wheel wells.
Andrew
If you look at the Dunlop "blu response" the manufacturer says both 15' and 16' types fall into class band "C" for fuel efficiency.
However, the 16 inch tyre is rated 69 decibels, while the 15 inch tyre is rated 67 decibels. That might not sound much difference, but decibels is measured in a logarithmic scale, so a difference of 1 decibel is considerable.
I believe sound is an indicator of efficiency, all else being equal.
Try a smaller lighter wheel maybe?
Tyres ratings compared:
dunlop blu response
195/65/16
195/65/15
However, the 16 inch tyre is rated 69 decibels, while the 15 inch tyre is rated 67 decibels. That might not sound much difference, but decibels is measured in a logarithmic scale, so a difference of 1 decibel is considerable.
I believe sound is an indicator of efficiency, all else being equal.
Try a smaller lighter wheel maybe?
Tyres ratings compared:
dunlop blu response
195/65/16
195/65/15
Last edited:
2015vwgolfdiesel
Top Post Dawg
IndigoBlueWagon
TDIClub Enthusiast, Principal IDParts, Vendor , w/
I wonder if something's off with your current FE calculation or with your car. Although what posters say about wheel weight and tire width is correct, I can't see it making that big a difference in FE in the same driving conditions. And to me it's a red flag whenever any manual transmission ALH shows less than 40 MPG. Seems to me that all your MPG numbers are a bit on the low side.
I won't rule out something is wrong but everything that I read about vehicles at sea level that run in excess of 70 mph for extended periods of time seem to get mpg in the low 40s without a tune. I wont say how much in excess I run above 70 but the fuel economy I saw with the 15" avus was what I had been expecting giving my driving conditions and road conditions. Just as a note I have gone thru the entire vehicle over the past 2 years and 100k miles you can see in some of my other threads,
intake cleaning, fuel filter, air filter, front/rear brakes, even a stuck caliper, all fluids, timing belt, vacuum lines, turbo actuator, timing adjust to green in vagcom.
intake cleaning, fuel filter, air filter, front/rear brakes, even a stuck caliper, all fluids, timing belt, vacuum lines, turbo actuator, timing adjust to green in vagcom.
turbovan+tdi
Top Post Dawg
- Joined
- Mar 23, 2014
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- Abbotsford, BC.
- TDI
- 2003 TDI 2.0L ALH, auto, silver wagon, lowered, Colt stage 2 cam, ported head,205 injectors, 1756 turbo, Malone 2.0, 3" exhaust, 18" BBS RC GLI rims. 2004 blue GSW TDI, 5 speed, lowered, GLI BBS wheels painted black, Malone stage 2, Aerotur
Check the MAF sensor as well. I noticed my MPG has dropped off and the power didn't seem to be there. I cleaned it last night and power is back, plus the exhaust drone that cropped up has gone. We'll see if the MPG come's back.
Steve-o
Veteran Member
Actually, it's not considerable: 1 dB is the smallest difference in sound pressure level that can be detected by the human ear. The 2 dB between these tires may well be barely perceptible to most people.
In truth, the dB difference is pretty much meaningless without discussing the frequency of the sound. Humans perceive much smaller dB differences around certain frequencies and don't perceive much larger dB differences around some others. So it's not just the sound pressure level but also the frequency composition of the sound that affects how we perceive the sound.
No its not meaningless.
We are not talking about perceived sound levels to the human ear (Psycho-Acoustics). We are talking about measured sound pressure (energy) as measured by the tyre manufacturer. This is about fuel economy when changing rim sizes.
We are then talking about 4 tyres, 4 times the change.
A Bel is an order of magnitude (10 times) of power and a decibel is one tenth that. Thus, 1 dB is a power change of about 26% (10^0.1). Frequently decibels are referenced to a standard power level. For example, dBm means dB referenced to a milliwatt where 0 dBm is one milliwatt, -10 dBm is 0.1 milliwatts, +20 dBm is 100 milliwatts, and so forth. This means each decibel is a different amount of watts depending where on the scale you are. At 0 dBm, one decibel means about 0.26 milliwatts but at +30 dBm (1 watt) one decibel is 0.26 watts.
For sound levels, the same kind of thing is true. 0 decibels SPL (Sound Pressure Level) is a specific amplitude of sound level (yes, there can be negative values). Going from 50 dB SPL to 51 dB SPL requires a lot less watts than going from 100 to 101 dB SPL.
Steve-o
Veteran Member
*shrug* I guess you're the expert. Wasn't clear to me we were not talking about psychoacoustics, though that is a (minor) issue for vehicles. I stand corrected.