Thousands of Miles of Mileage Records for My Mustang

Gas Mileage

Here's some interesting trivia about gas mileage. Have you ever wondered which brand, grade, or octane rating gives better gas mileage? Well, I've collected thousands of miles of data on a wide variety of brands, octane ratings, grades, etc. All this information is from my 1967 Ford Mustang. I have found these results interesting, I hope you do as well.


Overall Mileage

Here is a partial record of my gas mileage in my 1967 Ford Mustang. These records start with the first tank of gas I put into the Mustang after I purchased it used in May of 2008.

This table shows the brand, grade, and octane rating of gasoline I was purchasing, the odometer reading at the time of fill-up, and the date and location (when available) of the fill up. It also shows the number of miles traveled since the last fill up and the mileage since that last fill-up, as well as a running total of the mileage I have been receiving.

BrandOctaneOdometer ReadingGallonsMiles CoveredMiles Per GallonAverage Miles Per Gallon(Running Average)DateLocation
Cennex 88 159,306.7         Jul 14, 2008 Bozeman, MT
Exxon 88 159,359.5 4.549 52.8 11.61 11.61 Jul 19, 2008 Bozeman, MT
Cennex 88 159,457.3 3.697 97.8 26.45 19.03 Jul 19, 2008 Butte, MT
Cennex 88 159,661.8 9.484 204.5 21.56 19.87 Jul 19, 2008 Butte, MT
Holiday 88 159,745.1 3.571 83.3 23.33 20.74 Jul 19, 2008 Bozeman, MT
Holiday 88 159,903.6 10.825 158.5 14.64 19.52 Aug 17, 2008 Bozeman, MT
Cennex 88 160,016.3 7.526 112.7 14.97 18.76 Aug 29, 2008 Bozeman, MT
Holiday 85.5 160,179.3 6.868 163.0 23.73 19.47 Aug 31, 2008 Billings, MT
Exxon 85.5 160,320.4 5.537 141.1 25.48 20.22 Aug 31, 2008 Bozeman, MT
Cennex 88 160,437.3 7.946 116.9 14.71 19.61 Sep 29, 2008 Bozeman, MT
'76 88 160,523.5 4.293 86.2 20.08 19.66 Sep 29, 2008 Butte, MT
Holiday 88 160,713.1 10.767 189.6 17.61 19.47 Oct 16, 2008 Bozeman, MT
Cennex 85.5 160,826.8 8.124 113.7 14.00 19.01 Nov 27, 2008 Bozeman, MT
Holiday 85.5 160,976.6 7.171 149.8 20.89 19.16 Nov 28, 2008 Billings, MT
Exxon 85.5 161,117.3 7.992 140.7 17.61 19.05 Nov 28, 2008 Bozeman, MT
Cennex 85.5 161,253.4 10.493 136.1 12.97 18.64 Dec 9, 2008 Bozeman, MT
Exxon 87 161,392.3 6.873 138.9 20.21 18.74 Dec 16, 2008 Boulder, MT
Exxon 88 161,592.1 11.065 199.8 18.06 18.7 Dec 19, 2008 Bozeman, MT
Exxon 88 161,650.9 5.063 58.8 11.61 18.31 Dec 26, 2008 Bozeman, MT
Cennex 88 161,808.5 6.797 157.6 23.19 18.56 Dec 26, 2008 Billings, MT
Holiday 88 161,962.2 6.544 153.7 23.49 18.81 Dec 27, 2008 Bozeman, MT
Exxon 89 162,182.8 9.881 220.6 22.33 18.98 Dec 28, 2008 Anaconda, MT
Holiday 88 162,295.3 4.766 112.5 23.60 19.19 Dec 28, 2008 Bozeman, MT
Exxon 88 162,473.0 10.277 177.7 17.29 19.11 Jan 4, 2009 Bozeman, MT
Holiday 88 162,557.5 5.931 84.5 14.25 18.9 Jan 9, 2009 Bozeman, MT
Cennex 88 162,677.6 5.457 120.1 22.01 19.03 Jan 9, 2009 Butte, MT
Conoco 88 162,760.4 3.495 82.8 23.69 19.21 Jan 9, 2009 Bozeman, MT
Holiday 88 162,815.4 6.128 55.0 8.98 18.83 Jan 27, 2009 Bozeman, MT
Cennex 88 162,921.8 6.467 106.4 16.45 18.74 Jan 29, 2009 Butte, MT
Holiday 88 163,034.2 5.066 112.4 22.19 18.86 Jan 31, 2009 Bozeman, MT
Cennex 88 163,123.7 5.792 89.5 15.45 18.75 Feb 1, 2009 Butte, MT
Exxon 85.5 163,194.4 3.089 70.7 22.89 18.88 Feb 1, 2009 Helena, MT
Cennex 88 163,327.7 10.430 133.3 12.78 18.69 Feb 4, 2009 Butte, MT
Conoco 88 163,530.0 11.869 202.3 17.04 18.64 Feb 18, 2009 Butte, MT
Exxon 88 163,645.5 7.217 115.5 16.00 18.56 Mar 14, 2009 Helena, MT
Conoco 87 163,773.0 7.147 127.5 17.84 18.54 Mar 20, 2009 Butte, MT
Conoco 88 163,872.1 5.995 99.1 16.53 18.49 Mar 21, 2009 Bozeman, MT
Exxon 85.5 163,958.3 4.054 86.2 21.26 18.56 Mar 21, 2009 Butte, MT
Conoco 88 164,016.6 5.858 58.3 9.95 18.34 Mar 27, 2009 Butte, MT
Exxon 88 164,138.9 6.968 122.3 17.55 18.31 Mar 29, 2009 Bozeman, MT
Cennex 88 164,226.2 5.014 87.3 17.41 18.29 Mar 30, 2009 Butte, MT
Holiday 88 164,335.6 5.948 109.4 18.39 18.29 Mar 30, 2009 Bozeman, MT
Cennex 88 164,453.8 8.068 118.2 14.65 18.21 Apr 11, 2009 Butte, MT
Conoco 88 164,671.6 10.441 217.8 20.86 18.27 Apr 11, 2009 Laurel, MT
Conoco 88 164,722.5 2.023 50.9 25.16 18.43 Apr 12, 2009 Billings, MT
Exxon 88 164,902.9 11.702 180.4 15.42 18.36 Apr 12, 2009 Three Forks, MT
Cennex 88 164,988.8 5.608 85.9 15.32 18.29 Apr 21, 2009 Butte, MT
Sinclair 88 165,058.4 2.616 69.6 26.61 18.47 Apr 21, 2009 Helena, MT
Exxon 91 165,143.3 5.705 84.9 14.88 18.4 Apr 23, 2009 Butte, MT
Holiday 88 165,219.8 3.785 76.5 20.21 18.43 Apr 23, 2009 Bozeman, MT
Cennex 88 165,327.7 7.470 107.9 14.44 18.35 May 1, 2009 Butte, MT
Exxon 91 165,402.3 4.212 74.6 17.71 18.34 May 9, 2009 Butte, MT
Conoco 88 165,489.8 5.296 87.5 16.52 18.31 May 9, 2009 Bozeman, MT
Conoco 88 165,662.2 10.255 172.4 16.81 18.28 May 21, 2009 Butte, MT
Exxon 87 165,793.8 7.319 131.6 17.98 18.27 May 25, 2009 Missoula, MT
Exxon 85.5 165,968.6 9.628 174.8 18.16 18.27 May 30, 2009 Butte, MT
Exxon 88 166,040.1 3.420 71.5 20.91 18.32 May 30, 2009 Helena, MT
Exxon 91 166,138.4 5.396 98.3 18.22 18.31 Jun 3, 2009 Butte, MT
Exxon 87 166,261.8 6.122 123.4 20.16 18.35 Jun 3, 2009 Missoula, MT
Exxon 91 166,443.1 9.920 181.3 18.28 18.35 Jun 10, 2009 Butte, MT
Exxon 88 166,624.0 9.078 180.9 19.93 18.37 Jun 12, 2009 Bozeman, MT
Conoco 88 166,872.4 14.820 248.4 16.76 18.35 Jul 13, 2009 Butte, MT
Exxon 88 166,966.3 5.390 93.9 17.42 18.33 Jul 25, 2009 Helena, MT
Exxon 85.5 167,149.6 10.592 183.3 17.31 18.31 Aug 21, 2009 Anaconda, MT
Conoco 85.5 167,303.0 11.750 153.4 13.06 18.23 Oct 9, 2009 Butte, MT
Exxon 85.5 167,377.7 4.212 74.7 17.74 18.22 Oct 11, 2009 Helena, MT
Conoco 88 167,532.4 10.863 154.7 14.24 18.16 Nov 12, 2009 Butte, MT
Conoco 88 167,603.2 4.289 70.8 16.51 18.14 Nov 18, 2009 Butte, MT
Exxon 89 167,727.3 6.157 124.1 20.16 18.17 Nov 18, 2009 Missoula, MT
Conoco 88 167,884.7 9.724 157.4 16.19 18.14 Nov 26, 2009 Butte, MT
Holiday 88 168,132.0 11.699 247.3 21.14 18.18 Nov 27, 2009 Billings, MT
Cennex 88 168,366.7 12.367 234.7 18.98 18.19 Nov 27, 2009 Butte, MT
Exxon 89 168,510.3 8.845 143.6 16.24 18.17 Dec 2, 2009 Missoula, MT
Conoco 88 168,673.4 10.429 163.1 15.64 18.13 Dec 10, 2009 Butte, MT
Conoco 85.5 168,839.8 13.102 166.4 12.70 18.06 Feb 23, 2010 Butte, MT
Conoco 85.5 168,951.7 6.619 111.9 16.91 18.04 Feb 26, 2010 Bozeman, MT
Exxon 85.5 169,117.2 11.084 165.5 14.93 18 Apr 10, 2010 Butte, MT
Conoco 85.5 169,199.5 4.340 82.3 18.96 18.02 Apr 14, 2010 Butte, MT
Exxon 87 169,343.3 7.500 143.8 19.17 18.03 Apr 14, 2010 Missoula, MT
Conoco 85.5 169,506.5 9.335 163.2 17.48 18.02 May 7, 2010 Butte, MT
Conoco 88 169,656.8 12.267 150.3 12.25 17.95 Jul 7, 2010 Butte, MT
Exxon 87 169,782.5 5.454 125.7 23.05 18.01 Jul 7, 2010 Missoula, MT
Conoco 88 170,017.3 13.058 234.8 17.98 18.01 Aug 18, 2010 Butte, MT
Exxon 87 170,141.1 5.619 123.8 22.03 18.06 Aug 18, 2010 Missoula, MT
Conoco 85.5 170,326.0 10.631 184.9 17.39 18.05 Sep 15, 2010 Butte, MT
Exxon 87 170,449.5 5.358 123.5 23.05 18.11 Sep 15, 2010 Missoula, MT
Cennex 87 170,691.6 13.873 242.1 17.45 18.11 Oct 20, 2010 Butte, MT
Exxon 87 170,829.5 6.211 137.9 22.20 18.15 Oct 20, 2010 Missoual, MT
Exxon 85.5 171,083.4 15.136 253.9 16.77 18.14 Nov 18, 2010 Butte, MT
Cennex 88 171,179.3 4.039 95.9 23.74 18.2 Nov 18, 2010 Bozeman, MT
Conoco 85.5 171,287.0 7.419 107.7 14.52 18.16 Dec 14, 2010 Butte, MT
Exxon 87 171,427.7 6.502 140.7 21.64 18.2 Dec 15, 2010 Missoula, MT
Conoco 85.5 171,578.5 7.600 150.8 19.84 18.21 Dec 23, 2010 Butte, MT
Conoco 85.5 171,657.0 3.931 78.5 19.97 18.23 Dec 23, 2010 East Helana, MT
Conoco 89 171,889.3 11.145 232.3 20.84 18.26 Dec 23, 2010 Billings, MT
Holiday 85.5 171,944.0 3.446 54.7 15.87 18.24 Dec 26, 2010 Billings, MT
Exxon 88 172,182.5 13.016 238.5 18.32 18.24 Dec 26, 2010 Helena, MT
Cennex 87 172,302.6 8.157 120.1 14.72 18.2 Jan 16, 2011 Butte, MT
Exxon 87 172,466.5 9.252 163.9 17.72 18.2 Jan 19, 2011 Missoula, MT
Exxon 85.5 172,590.4 6.221 123.9 19.92 18.21 Jan 24, 2011 Butte, MT
Conoco 85.5 172,611.4 2.610 21.0 8.05 18.11 Feb 7, 2011 Butte, MT
Conoco 85.5 172,724.4 5.293 113.0 21.35 18.14 Feb 9, 2011 Butte, MT
Conoco 87 172,843.5 5.357 119.1 22.23 18.18 Feb 9, 2011 Missoula, MT
Exxon 85.5 172,975.8 6.940 132.3 19.06 18.19 Feb 12, 2011 Butte, MT
Conoco 85.5 173,097.3 6.539 121.5 18.58 18.2 Feb 23, 2011 Anaconda, MT
Exxon 87 173,207.9 5.443 110.6 20.32 18.22 Feb 23, 2011 Missoula, MT
Exxon 85.5 173,356.1 8.707 148.2 17.02 18.21 Mar 4, 2011 Butte, MT
Exxon 85.5 173,537.4 11.945 181.3 15.18 18.18 Apr 12, 2011 Butte, MT
Cennex 87 173,644.7 5.845 107.3 18.36 18.18 Apr 22, 2011 Bozeman, MT
Holiday 85.5 173,869.2 9.895 224.5 22.69 18.22 Apr 24, 2011 Billings, MT
Conoco 85.5 174,029.7 6.813 160.5 23.56 18.27 Apr 24, 2011 Manhattan, MT
Cennex 87 174,094.1 3.514 64.4 18.33 18.27 Apr 24, 2011 Butte, MT
Exxon 85.5 174,214.5 8.906 120.4 13.52 18.23 May 22, 2011 Butte, MT
Exxon 85.5 174,361.6 7.164 147.1 20.53 18.25 May 22, 2011 Big Timber, MT
Conoco 85.5 174,450.4 3.850 88.8 23.06 18.29 May 22, 2011 Billings, MT
Holiday 85.5 174,567.5 5.396 117.1 21.70 18.32 May 23, 2011 Billings, MT
Cennex 87 174,706.4 6.538 138.9 21.25 18.34 May 23, 2011 Bozeman, MT
Exxon 85.5 174,809.6 5.151 103.2 20.03 18.36 May 23, 2011 Helena, MT
Conoco 85.5 174,878.7 3.355 69.1 20.60 18.38 May 24, 2011 Butte, MT
Conoco 85.5 175,049.2 11.432 170.5 14.91 18.35 Jul 8, 2011 Butte, MT
Conoco 85.5 175,113.5 2.718 64.3 23.66 18.39 Jul 8, 2011 Manhattan, MT
Conoco 85.5 175,268.5 7.446 155.0 20.82 18.41 Jul 11, 2011 Manhattan, MT
Exxon 85.5 175,554.3 16.832 285.8 16.98 18.4 Sep 1, 2011 Butte, MT
Conoco 85.5 175,692.9 10.298 138.6 13.46 18.36 Oct 14, 2011 Butte, MT
Conoco 85.5 175,811.6 10.105 118.7 11.75 18.31 Nov 8, 2011 Butte, MT
Conoco 85.5 175,923.8 10.296 112.2 10.90 18.25 Dec 9, 2011 Butte, MT
Conoco 85.5 176,031.2 9.388 107.4 11.44 18.19 Jan 21, 2012 Butte, MT
Conoco 85.5 176,108.0 7.721 76.8 9.95 18.13 Mar 7, 2012 Butte, MT
Exxon 87 176,233.4 6.053 125.4 20.72 18.15 Mar 7, 2012 Missoula, MT
Conoco 85.5 176,356.8 5.393 123.4 22.88 18.19 Mar 8, 2012 Butte, MT
Conoco 85.5 176,489.7 6.588 132.9 20.17 18.2 Mar 15, 2012 Butte, MT
Conoco 85.5 176,540.9 4.057 51.2 12.62 18.16 Mar 28, 2012 Butte, MT
Exxon 87 176,669.3 5.718 128.4 22.46 18.19 Mar 28, 2012 Missoula, MT
Conoco 85.5 176,830.1 8.142 160.8 19.75 18.2 Apr 4, 2012 Butte, MT
Exxon 87 176,975.0 6.292 144.9 23.03 18.24 Apr 4, 2012 Missoula, MT
Conoco 85.5 177,117.1 7.199 142.1 19.74 18.25 Apr 6, 2012 Butte, MT
Holiday 85.5 177,203.5 3.366 86.4 25.67 18.3 Apr 6, 2012 Bozeman, MT
Holiday 85.5 177,392.9 8.759 189.4 21.62 18.33 Apr 8, 2012 Billings, MT
Holiday 85.5 177,534.5 6.286 141.6 22.53 18.36 Apr 8, 2012 Bozeman, MT
Conoco 85.5 177,640.3 5.324 105.8 19.87 18.37 Apr 11, 2012 Butte, MT
Exxon 87 177,766.6 3.984 126.3 31.70 18.47 Apr 11, 2012 Missoula, MT
Conoco 85.5 177,911.5 8.135 144.9 17.81 18.46 Apr 15, 2012 Butte, MT
Conoco 87 178,034.0 5.291 122.5 23.15 18.49 Apr 15, 2012 Missoula, MT
Conoco 85.5 178,224.2 10.495 190.2 18.12 18.49 May 1, 2012 Butte, MT
Conoco 85.5 178,354.3 9.400 130.1 13.84 18.46 Jun 4, 2012 Butte, MT
Conoco 85.5 178,493.9 8.558 139.6 16.31 18.44 Jul 16, 2012 Butte, MT
Conoco 85.5 178,556.7 3.356 62.8 18.71 18.45 Jul 18, 2012 Butte, MT
Safeway 87 178,686.6 5.025 129.9 25.85 18.5 Jul 18, 2012 Missoula, MT
Exxon 85.5 178,884.4 9.584 197.8 20.64 18.51 Aug 17, 2012 Butte, MT
Holiday 88 179,007.5 7.468 123.1 16.48 18.5 Aug 15, 2012 Bozeman, MT
Conoco 85.5 179,094.0 3.265 86.5 26.49 18.55 Aug 15, 2012 Butte, MT
Safeway 87 179,221.4 4.612 127.4 27.62 18.61 Aug 15, 2012 Missoula, MT
Conoco 85.5 179,353.7 6.129 132.3 21.59 18.63 Aug 20, 2012 Butte, MT
Conoco 85.5 179,496.6 9.943 142.9 14.37 18.6 Sep 24, 2012 Butte, MT
Conoco 85.5 179,660.3 13.013 163.7 12.58 18.56 Nov 5, 2012 Butte, MT
Exxon 85.5 179,792.9 10.987 132.6 12.07 18.52 Dec 1, 2012 Butte, MT
Conoco 85.5 179,986.4 16.397 193.5 11.80 18.48 Jan 21, 2013 Butte, MT
Conoco 85.5 180,170.2 14.753 183.8 12.46 18.44 Feb 27, 2013 Butte, MT
Cennex 85.5 180,312.5 11.140 142.3 12.77 18.4 Mar 25, 2013 Butte, MT
Cennex 85.5 180,471.8 12.796 159.3 12.45 18.37 May 1, 2013 Butte, MT
Cennex 85.5 180,645.8 12.567 174.0 13.85 18.34 Jun 14, 2013 Butte, MT
Cennex 85.5 180,810.2 10.027 164.4 16.40 18.33 Jul 15, 2013 Butte, MT
Cennex 85.5 181,003.2 10.954 193.0 17.62 18.32 Jul 30, 2013 Butte, MT
Cennex 85.5 181,208.7 12.665 205.5 16.23 18.31 Aug 24, 2013 Butte, MT
Cennex 85.5 181,380.4 10.758 171.7 15.96 18.29 Sep 17, 2013 Butte, MT
Cennex 85.5 181,527.5 10.931 147.1 13.46 18.27 Oct 8, 2013 Butte, MT
Cennex 85.5 181,667.1 9.503 139.6 14.69 18.24 Oct 30, 2013 Butte, MT
Cennex 85.5 181,795.4 10.488 128.3 12.23 18.21 Nov 26, 2013 Butte, MT
Cennex 85.5 181,881.5 9.415 86.1 9.14 18.15 Dec 13, 2013 Butte, MT
Cennex 85.5 182,023.4 10.070 141.9 14.09 18.13 Jan 7, 2014 Butte, MT
Exxon 85.5 182,168.1 9.905 144.7 14.61 18.11 Jan 31, 2014 Butte, MT
Cennex 85.5 182,283.0 10.071 114.9 11.41 18.07 Mar 4, 2014 Butte, MT
Cennex 85.5 182,407.8 9.832 124.8 12.69 18.04 Mar 28, 2014 Butte, MT
Cennex 85.5 182,538.0 10.157 130.2 12.82 18.01 Apr 24, 2014 Butte, MT
Cennex 85.5 182,674.0 9.762 136.0 13.93 17.99 May 16, 2014 Butte, MT
Cennex 85.5 182,806.3 8.919 132.3 14.83 17.97 Jun 21, 2014 Butte, MT
Cennex 85.5 182,946.5 9.212 140.2 15.22 17.95 Aug 7, 2014 Butte, MT
Cennex 85.5 183,088.4 9.139 141.9 15.53 17.94 Sep 3, 2014 Butte, MT
Cennex 85.5 183,256.2 11.007 167.8 15.24 17.92 Oct 7, 2014 Butte, MT
Cennex 85.5 183,339.1 6.398 82.9 12.96 17.89 Nov 5, 2014 Butte, MT
Cennex 85.5 183,425.4 8.416 86.3 10.25 17.85 Dec 17, 2014 Butte, MT
Cennex 85.5 183,515.7 9.261 90.3 9.75 17.81 Jan 30, 2015 Butte, MT
Cennex 85.5 183,629.5 9.336 113.8 12.19 17.78 May 2, 2015 Butte, MT
Cennex 85.5 183,727.8 9.033 98.3 10.88 17.74 Jul 31, 2015 Butte, MT
Cennex 85.5 183,844.8 9.059 117.0 12.92 17.71 Sep 15, 2015 Butte, MT
Cennex 85.5 183,959.7 9.086 114.9 12.65 17.69 Sep 28, 2015 Butte, MT
Cennex 87 184,033.0 8.813 73.3 8.32 17.64 Apr 2, 2016 Butte, MT
Conoco 87 184,102.4 6.261 69.4 11.08 17.6 Jun 4, 2016 Butte, MT
Cennex 87 184,254.9 9.722 152.5 15.69 17.59 Jun 18, 2016 Butte, MT
Cennex 87 184,384.8 9.486 129.9 13.69 17.57 Aug 25, 2016 Butte, MT
Exxon 87 184,499.2 8.726 114.4 13.11 17.55 Sep 7, 2016 Butte, MT
Exxon 87 184,660.4 15.474 161.2 10.42 17.51 Oct 12, 2016 Butte, MT
Cennex 87 184,767.3 10.371 106.9 10.31 17.47 Oct 26, 2016 Butte, MT
Exxon 87 184,918.9 14.086 151.6 10.76 17.44 Nov 22, 2016 Butte, MT
Cennex 87 185,017.2 9.680 98.3 10.15 17.4 Dec 2, 2016 Butte, MT
Cennex 87 185,087.0 9.555 69.8 7.31 17.35 Jan 8, 2017 Butte, MT
Cennex 87 185,156.7 7.595 69.7 9.18 17.31 Mar 1, 2017 Butte, MT
Cennex 87 185,250.6 10.522 93.9 8.92 17.26 Mar 31, 2017 Butte, MT
Exxon 87 185,362.8 11.063 112.2 10.14 17.23 Apr 29, 2017 Butte, MT
Exxon 87 185,526.2 13.519 163.4 12.09 17.2 Jul 29, 2017 Butte, MT
Cennex 87 185,669.8 11.147 143.6 12.88 17.18 Oct 17, 2017 Butte, MT
Cennex 87 185,816.5 11.902 146.7 12.33 17.16 Oct 26, 2017 Butte, MT
Cennex 87 185,924.1 9.968 107.6 10.79 17.12 Nov 3, 2017 Butte, MT
Cennex 87 186,024.9 10.212 100.8 9.87 17.09 Nov 9, 2017 Butte, MT

I, of course, make no guarantees about what kind of gas mileage you may receive in your vehicle, even if it is a '67 Mustang with an L200 and a couple hundred thousand miles under the hood, because there are way too many variables that come into play...