: Surprising Mileage and a Tire Question



sapugh
10-07-11, 02:17 PM
Hey Folks,
Just drove from Seattle to Portland and back and average over 20MPG, Closer to 20.5 according to the DIC. Mostly on cruise and around 75-78MPH. I have a 2011 V-Couple, Manual Transmission.

Second Question, I really am missing Ultra High Performance All Season. I ran Michelin Pilot Sport A/S Plus on my previous vehicles and loved them but they do not seem to be available in OEM sizes. Other than going to 20" Wheels any other ideas?

Thanks,
Scott

Cub Cadet
10-07-11, 02:26 PM
Your mileage is not uncommon. I have averaged 24mpg with the cruise set at 69mph. One thing to remember... if you are using the display to check your mileage, you will have to *reset* it (the avg. mileage meter) at each fill-up. If not, it averages over the total mileage and will be pretty far off over time.
As for tires... I will save you the effort. I have spent a few months searching for an all season tire... and I refused to go with Michelins. What I came up with is the Bridgestone 970AS Pole position tire. The sizes that I got are 255/35 - 19 in Front and 295/30 - 19 in the rear. These actually do look really nice and will be just fine for the snow. The only downfall is that the front tire could really stand to be a 265 wide tire... just could not find any matching sets for that though. The reason I say this is because GM made a front width that just doesn't fit tires very well. The stock width Michelin does not look good on the wheel.... looks like the wheel is too wide for the tire.

thebigjimsho
10-08-11, 03:57 PM
Hey Folks,
Just drove from Seattle to Portland and back and average over 20MPG, Closer to 20.5 according to the DIC. Mostly on cruise and around 75-78MPH. I have a 2011 V-Couple, Manual Transmission.

Second Question, I really am missing Ultra High Performance All Season. I ran Michelin Pilot Sport A/S Plus on my previous vehicles and loved them but they do not seem to be available in OEM sizes. Other than going to 20" Wheels any other ideas?

Thanks,
ScottScott are you hung up on having square tires? If not, what is your criteria? In stock sizes, all seasons are limited.

Rule12b
10-08-11, 04:30 PM
Holy crap. I can't even fathom gettting 20 mpg. I average between 8 and 10 mpg around town and at best, 15-17 on a road trip, (although setting the cruise at 69 would be a level of hell reserved especially for me).

Gary Wells
10-09-11, 06:44 AM
The DIC is not near as accurate as computing your mileage the old fashioned way. I check the DIC against a manual mileage check every time that I fill up. And out of about 15 fill-ups and / or checks against the manual system the DIC reads optimistic about 6 out of every 7 checks, and out of about every 5 checks, it is way optimistic. Like 1.5-3.5 MPG.
Cub Cadet: I would sure like to see what your real mileage checks out to be. So far, nobody on the forum has ever reported 24 MPG, let alone average. A couple of people have reported 21 or 22 on isolated incidents. So not saying that you are incorrect, only that your DIC is very optimistic.
FWIW, IMHO, & HTH
BTW, my records, calculations, and checks are for a '09 CTS-V, bone stock, about 7K miles currently, and a auto (A6) transmission.

thebigjimsho
10-09-11, 01:10 PM
Must be those square tires he's rolling on to get 24mpg. lol.

deckofficer
10-09-11, 03:54 PM
The DIC is not near as accurate as computing your mileage the old fashioned way. I check the DIC against a manual mileage check every time that I fill up. And out of about 15 fill-ups and / or checks against the manual system the DIC reads optimistic about 6 out of every 7 checks, and out of about every 5 checks, it is way optimistic. Like 1.5-3.5 MPG.
Cub Cadet: I would sure like to see what your real mileage checks out to be. So far, nobody on the forum has ever reported 24 MPG, let alone average. A couple of people have reported 21 or 22 on isolated incidents. So not saying that you are incorrect, only that your DIC is very optimistic.
FWIW, IMHO, & HTH
BTW, my records, calculations, and checks are for a '09 CTS-V, bone stock, about 7K miles currently, and a auto (A6) transmission.

Has your V been chipped? Mine is stock and reads right on. I have a 4 tankful average of 19.7 mpg and this friday will be taking a 700 mile one way trip and I expect 21~22 MPG. I'll report back what I got.

Gary Wells
10-09-11, 07:17 PM
FWIW, IMHO, & HTH......................BTW, my records, calculations, and checks are for a '09 CTS-V, bone stock, about 7K miles currently, and a auto (A6) transmission.

No, deckofficer, bone stock, and to make matters worse, I have looked for a root cause for some time now.
Mileage comparisons (started 06-22-2011):


09 Cadillac CTS-V: start: mileage: 3344:

ampg: actual mileage per gallon as computed manually, tank fill to tank fill
cmpg: computer DIC mileage per gallon as computed by the DIC

---date-----miles---miles----gals-----price----cost----ampg--cmpg.--spd---range
06-02-11---3516---172.0---11.430---4.199---48.00---15.0----N/A---00.0---000
06-14-11---3694---178.0---11.222---4.099---46.00---15.9----N/A---00.0---000
06-18-11---3823---129.0---13.220---4.099---40.00---13.2----N/A---00.0---000
06-22-11---3965---142.0---08.294---4.099---34.00---17.1----15.2---00.0---000
07-06-11---4092---126.4---08.335---3.959---33.00---15.1----15.3---00.0---000
07-12-11---4252---160.3---11.141---4.039---45.00---14.4----15.1---00.0---264
07-18-11---4392---139.4---08.913---4.039---36.00---15.6----15.4---31.6---266
07-21-11---4509---117.8---08.170---4.039---33.00---14.4----15.5---32.3---263
07-25-11---4656---146.0---09.752---3.999---39.00---15.0----15.4---33.0---278
07-30-11---4849---193.1---12.753---3.999---51.00---15.1----15.2---31.1---283
08-03-11---4989---140.7---08.501---3.999---34.00---16.6----17.3---39.0---278
08-09-11---5150---160.1---10.053---3.979---40.00---15.9----16.3---34.7---283
08-11-11---5258---108.2---06.568---3.959---26.00---16.5----16.4---34.5---285
08-13-11---5375---116.8---07.310---3.899---28.50---16.0----16.9---36.3---284
08-19-11---5563---188.0---12.054---3.899---47.00---15.6----15.8---32.3---263
08-23-11---5731---168.5---10.662---3.939---42.00---15.8----16.1---33.4---276
09-06-11---5948---217.0---14.666---4.159---61.00---14.8----16.0---33.8---287
09-13-11---6176---228.1---15.704---4.139---65.00---14.5----15.5---32.6---282
09-19-11---6352---175.4---11.717---4.139---48.50---15.0----15.6---31.4---275
09-24-11---6582---229.6---13.730---4.079---56.00---16.7----15.8---31.9---299
09-27-11---6755---173.5---11.141---4.039---45.00---15.6----16.0---31.9---284
10-02-11---6921---165.7---11.501---4.039---46.45---14.4----14.9---27.5---265

deckofficer
10-09-11, 08:39 PM
Gary,

Did a crude calculation and considering not always level fuel islands and not always a fully pressed tank on fill up, I believe your computer is pretty close, but as you said, optimistic. ampg 15.48, cmpg 15.77.

mountainv
10-09-11, 08:52 PM
The Bridgestone 970AS Pole Position tires (255/35-19, 295/30-19) sound like what I am looking for as a winter tire for North Carolina. Any problem with the slight size variation from the stock Michelins? Thanks....

thebigjimsho
10-09-11, 09:19 PM
Usually, you want a taller tire for dealing with snow. I was thinking of getting Continental ExtremeContact DWS for the V last winter in 245/45 19F, 275/40 19R sizes.

RC51V2
10-17-11, 12:45 PM
Speaking of mileage, this last weekend I drove from San Bernardino to Zion. Averaged 21.3 mpg there on the DIC (20.8 calculated) and 20.3 back on the DIC (19.7 calculated) and that was at an average speed of 80 mph. I really wasn't trying to drive easy, and I passed when and where needed and had sections up in the mid 90 mph range. Could not believe the mileage considering I usually average around 14-15 mpg in town. Best part was never needing to slow down in the twisty sections because the car stuck to the road so damn well, and passing long lines of cars going uphill when everyone else was topped out.