dmk9561 Posted September 11, 2009 Report Share Posted September 11, 2009 95 Cadillac SLS 4.6 275hp Northstar The average display says 17.3 right now. I've only had the car about a month, and I drove it a couple of weeks with a misfire that took the average down from over 18 to 16.0. I figure it'll probably find a level at about 17.3-17.5 and stay there, as my driving is pretty repetitive and consistent. That's within 1 mpg of what my 3.8l Oldsmobile 98 had been getting. My dad and I drove it on a round trip that was over 1,000 miles and got mid 20s, but that was several years ago when the car had fewer miles. I've no reason to doubt it would still do that, though. I'm not at all displeased with the Northstar's mileage. For a 4000 lb car with surplus power, it gets excellent mileage. Link to comment Share on other sites More sharing options...
Texas Jim Posted September 12, 2009 Report Share Posted September 12, 2009 2006 DTS Performance Sedan 4.6 NorthStar 300+ HP 67,000 + miles Most of my driving...even in town is on freeways. Usually get around 20 in town..."IF" I keep my foot out of it. On the highway, it varies from a high of around 24/25 if I keep it down to 70 to a low of around 21 if I am in a hurry...which I usually am. In a hurry, means 85 to 90. Long runs at 100+ drops it to about 18. Link to comment Share on other sites More sharing options...
BLAZINRONG Posted September 16, 2009 Report Share Posted September 16, 2009 01 DTS... HA HA 13.2MPG BIG RIMS CAUSE LIL MPG PLUS A LOT OF WAIT IN THE TRUNK,... Link to comment Share on other sites More sharing options...
human Posted September 23, 2009 Report Share Posted September 23, 2009 My '97 Deville Concours (4.6L, 300hp Northstar) does about 16 in town and 25 on the highway. This compares somewhat favorably with my late lamented 1998 Olds Aurora, which would get about 18 around town and 28 on the highway. The Aurora had a 4.0L Northstar and weighed a good 500lbs less than the Deville, but they both shared the 3.71 final drive ratio. I just replaced the ignition coils in the Deville and am interested to see if fuel economy improves. To maximize fuel economy, use premium gas, drive conservatively, and perform regular maintenance. Post your avg MPG and offer advice to improve fuel economy. I have a 2000 STS and the dash is giving me a 19.8 avg MPG with city driving. I havent had it long enough to do a highway test, but this weekend I will be making a trip out of town and will post the results. I guess I cant complain when the car was advertised as having 17 city and 28 hwy with 300 horses racing down your neck!! The secret to flying is to throw yourself at the ground--and miss! --Douglas Adams Life, The Universe, and Everything Link to comment Share on other sites More sharing options...
Scarabeo500gt Posted September 8, 2010 Report Share Posted September 8, 2010 I am getting 14mpg in city and 23mpg on Highway in my 2002 STS 300 hp and 17mpg in city and 28mpg on Highway in my 2001 Deville 275 hp I do check them both a lot!!! Link to comment Share on other sites More sharing options...
Texas Jim Posted September 8, 2010 Report Share Posted September 8, 2010 We just came back from a 4000 + mile vacation. 2006 DTS Performance Sedan with 88,000+ miles Most tanks averaged 21 to 22. Most highway speeds were around 80 / 90. Not bad for a big ol' comfortable car. Link to comment Share on other sites More sharing options...
gregj1006 Posted September 9, 2010 Report Share Posted September 9, 2010 2003 Deville, 90,250 miles approx. avg mpg 18 city/24 hgwy Link to comment Share on other sites More sharing options...
brcree Posted October 15, 2010 Report Share Posted October 15, 2010 I have a 94 Deville and avg. 21.8 mpg. around town......almost 23 on the highway. I have 196,000 on the clock. Link to comment Share on other sites More sharing options...
RLBjerklund Posted March 1, 2011 Report Share Posted March 1, 2011 My 1993 Deville gets 20MPG in city and between 25-30MPG on hwy. I hope replacing the ISC will increase the gas mileage, but I can'treally complain as the last car I drove got 12 MPG (yep, I was driving a 53 Ford with a Mopar 225 inline six.) My dads car. He races it and has the nickname Fopar due to that car. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.