My 06 DTS gets between 22 - 24 city mpg and 31mpg at 80mph to 36 mpg at 60mph on a Canadian gallon.So taking 20% off for US gallon gives you 17 to 19 and 25 to 29 Hwy.
In the winter it is 1 to 2 mpg less due to more idling and using remote start.
Andy1
My 06 Dts gets 21 to 23 mpg in the city and between 32 and 36mpg on the highway. Of course thats on a Canadian gallon. (I've converted everything from our litres and Kms)
At 100 kph (62mph) I get 36 mpg and at 120kph, (75mph) I get about 32 mpg.
Over 80mph it drops to 29mpg cdn or 23 US mpg.
If you take 20% off for the smaller US gallon, you get 17 to 19 city and 26 to 29 mpg hwy.
I convert from amount driven on trip odometer, and litres on pump.
I also use fuel injector cleaner every 3rd or 4th tank, and 5/30 synthetic oil. The synth oil is more for starting at -35, but I think it does give 1 mpg+
In the winter, it drops about 2 mpg using rmote start to warm car.
Tires on it now Contiental Touring Contact A/S size 235/55/17
looking at Continental ContiPro contacts which have higher rating and Pirrelli P Nero Ultra High Perfomance all season tires all research done at Tirerack.com
Conto Pro's same price as whats on it now but have a little better rarting and the Pirreli's get good reviews from people who have put them on htier DTS.
Just drive 300 miles on I-95 at approx 75MPH with wife and two medium sized kids in the back with moderate luggage (in 100 degree heat!! man you gotta love air conditioned seats).
I got average 25MPG in my 2006 Lux II with factory Conti's for the trip. Tire pressue was reading about 37 lbs while on the road. I haven't blown them up lately, and glad I didn't considering the bone jarring, dental-work rattling condition of I-95 through SC. The tires are at about 31lbs in the mornings right now.
We checked the air and cabin filter they were both semi dirty so we called Caddy dealer they put new ones in for free and was talking to service guy and he said to aair up tire to 35 lbs psi they would last better and ride better well they were at 31 lbs psi and i aired them up to 34 and they do ride better actually tried 35 but that waw stoo much so 33/34 lbs is best for me.
Teh Caddy dealer is a Contintal dealer will prolly go woth Conti-pros when its time for tire change.
My DTS Performance came with Bridgestones and they seem fine, though they've only 1500 miles on them now. I had Conti Touring on my '05 300C. They needed replacement at 30,000 miles and were pretty noisy and not exactly great handling. The car was very squirrel-y handling. Switched to Goodyear Assurance. They were probably twice the price of the Conti's but they rode quieter, improved handling by at least 100%, and had a 60,000 mile tread guarantee. I would have to say, though, that they weren't too impressive on wet pavement. Sold the car with only 8,000 miles on the tire so don't know if they'd go the 60K. Others on the Edmund's Chrysler website have complained of reduced fuel consumption with the Goodyears. I really didn't really notice any difference.
Personally I love Michelin and have always had good experience with them. Would have put them on the Chrysler if they were available in that size....
Andy1 here in Calgary
I agree the stock Contis on my 06 L2 are a bit soft and squirrelly but they are very good in the winter. I keep mine at 32psi with a good digital tire gauge. The roads here a bit rough at times so 35 is too harsh. Also at 35 psi I think the center of the tire may wear faster.
My next tires may be the michelin MXV4 Exaltos from Costco. Supposed to have very low rolling resistance for better gas mileage, and excellent handling dry and wet. Plus at Costco here they use Nitrogen, so no big changes in tire pressure with hot or cold. Keep them at 32 and an hour on the highway they should still be at 32.
Our 2002 DHS averaged 29.5 MPG on a 3500 mile trip to Florida from the Eastern Shore. That included running around and sightseeing during the month. We have gotten as high as 32MPG. I would point out that this is driving in terrain that is all flat but that is where we do most of our driving. If we travel to areas with a lot of hills or mountains then the mileage suffers from pulling all that weight around. Most of our driving, however, is in flat areas.
The only thing that has been holding me back from getting a new Caddy [now have 125K] is what seems to be fuel mileage on these new cars that has declined. One would think in 6 years there would have been some improvement. I am also convinced that my current DHS gets better mileage than the new CTS that I have considered for the next car. This is pretty frustrating. A NorthStar that loafs along @1500rpm doing 60+MPH gets impressive mileage.
I just made a command decision to buy a new set of tires for the car and extend ownership time hoping GM might catch on with fuel prices this high and pay a little more attention to mileage and less to pushing up the HP.
