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Buick Lucerne: Real World MPG



  • lane2lane2 Posts: 28
    Thanks. What octane were you using on your trip? Would like to try a tank of the same octane to for the trip up to the mountains and if I get the mpg like you did, not bother checking the other octanes for efficiency.
  • lane2lane2 Posts: 28
    Since I had a full tank of 87 octane, tried all 87 octane for this trip. Had a high of 26 mpg up and back home and a low of 19.8 mpg in the snow in the mountains, very slow up and down. Total of about 950 miles. Very pleased with the performance, no pinging , and plenty of power. Just me and my wife but LOTS of luggage plus golf clubs. Guess I will try 93 octane for the next trip and see if there is any difference in mpg.
  • Just bought a used 2008, 14K miles, CXL as a Certified Used Car from the dealership and love this car. My previous one was a 1999 Regal LS, and I loved it too. The Regal was the same engine and got 24MPG. My old car broke down for the very last time just before Christmas. I did not have many choices for replacements, because dealers have kept inventories very low. My new Lucerne is only getting about 18MPG. I live in central west NJ, and the nearest gas station and town is 5 miles away in any direction. I drive 50 miles round trip to work, but have only used the car twice so far to get there. Most driving is county roads at around 50mph and highway at 70mph. What can I do to increase MPG? I have heard premium gas, new K&N filters, fuel system cleaner, and tire pressure. Is there anything else I should seriously consider?
  • oldguy8oldguy8 Posts: 12
    I am satisfied with my mileage on my V6 on a loaded trip to Florida I averaged 27mpg think this would have been better had I realized this engine actually gets better mileage at 70 than at 60, the last fill up was at 70 on the interstate and was 28.6 Actual, I find the computer will be high sometimes and low others and right on at times. 17-20 normal for in town driving depends on the stop lights and the duration of those lights.
  • I worked on the 3800 line at Buick until the last one was built which was Friday, August 22, 2008 at about 12:00pm. I ran the dept that checked each engine for faults and leaks. If an engine was rejected, I analizied the computer info and preformed the basic repairs. Sometimes the decision was a bad cylinder bore or maby a lifter bore too tight causing vibration or too loose causing an oil pressure problem. Many situations.
    The answer to the question on oil used during assembly is 10w30.
    Remember that in a mass production situation there are many variables which could result in varying fuel millage. All the testing equipment was computer controled, but also had tolerances for the 12 different tests. If an engine was pushing the limits of one or more of the tests and the computer accepted these it sent the engine out. Each engine has its own personality which was developed through machining, parts, and the assembly process and a combination of these could lead to posible lower fuel millage. Any questions just ask and maybe I can shed some light.
  • kenb757kenb757 Posts: 149
    Does GM use a special break-in oil or additve for the initial factory fill, or is it the over-the-counter (Goodwrench?) stuff? My DTS got about 2 mpg better (at 20 mpg) than my Lucerne Super, but I think it has more to do with tuning and the final drive ratio, than with other inherent differences in the Northstar V-8s.
  • buicks5buicks5 Posts: 20
    If you happen to ever see this reply, then please note that I have a 2000 Park Ave Ultra with the supercharged 3.8. This supercharged 3.8 now has 204,000 miles on it and is the best running car and engine of any vehicle i have ever owner at any miles on a vehicle. It does use a tiny amount of oil (1qt at 2500-3500 miles), past the rear valve cover, which is normal. GM replaces the gaskets on other applications, because of possible fire from dripping oil, but not an issue on this car.

    The supercharger uses a tiny about of oil at about 5,000 miles; maybe 1/4-1/2 pint. Engine starts instantly, does not smoke under any conditions, and pulls hard with good acceleration. I have always used Mobil 1 10/30 with Mobil 1 filter (extra fine filtration).

    The water pump is still good and tight and the dealer says the timing chain generally does not require replacement, even at high miles...a rarity.

    Fuel economy is 24-25mpg at 75-80m mph and 29-31mpg at 55-60mph. Commuting at 17 miles one way is about 21-22mpg.

    Shame that GM found it necessary to cease production. I had a 3.8 in a Toronado and it was also bulletproof. What a terrific engine!
  • I recently purchased a 2007 Lucerne CXL with 3800 series II and am only getting 22 MPG highway. This is very surprising to me as I had two Park Avenues, 1996 and 1999 with that engine and consistently got 29 MPG highway. I was expecting similar or better with the smaller Lucerne.
    This car olnly has 17,000 miles and everything seems to run and shift fine. I had the oil changed and tires rotated right after I got it 2 months ago.
    Any suggestions for trying to increase the MPG on highways?
    I appreciate your thoughts.
  • gmcustsvcgmcustsvc Posts: 4,251
    Hi Michaeldm,

    Some tips for improving your vehicle fuel economy include using Drive (D) as opposed to 2nd and 3rd gear; letting your vehicle heat up in cold temperatures; making sure no indicator lights are on your vehicle (particularly the Check Engine Light). Also remember that different driving conditions produce different fuel economies (ex. freeway driving versus city driving). Also try resetting your AVG ECONOMY on the display, as this allows for a more accurate reading of the average fuel economy. Please let me know if you have any other questions.

    Amber N.
    GM Customer Care
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