can anybody tell me from their own experience what kind of fuel mileage to expect from a 2007 m2 with a 250 hp cat motor,6 speed allison auto, rear axle 5.29 gears, i pull a 48ft hotshot that weighs empty 10k.
Posted 2009-09-12 2:18 PM (#2518 - in reply to #2517) Subject: RE: 2007 freightliner m2
Posts: 176
Just my opinion, I would guess NOT VERY GOOD with 5.29 gears, although you should be able to haul anything you want too. I think unloaded with no trailer and easy driving you may see 10 to 11 or so. Loaded maybe 8!
We use on last year with 4.10's and hauling a 15-klb horse trailer would get right at 14@70mph.
Posted 2009-09-23 2:25 PM (#2521 - in reply to #2516) Subject: RE: 2007 freightliner m2
Location: Colorado
You want to see which Allison it has in it. It may be a double overdrive transmission, so it might not be as bad as you think. If it's an Allison 3060 or 3066, the top two gears will be a .75 and .65 overdrive. You said this has a 250 HP C7. That's kind of low on the horsepower to my way of thinking. If it was a bigger engine with more torque, 250 HP wouldn't concern me too much.
Posted 2009-09-28 9:32 PM (#2526 - in reply to #2516) Subject: RE: 2007 freightliner m2
Posts: 176
Still with 5.29 gears your mileage is history! No matter what torque or horse power you have.
Same deal has having a F-450 or F-550 with 4.30's or 4.88's with a 7.3L POWERSTROKE DIESEL. The 4.30's will get you around 14 give or take depending on your driving habbits and the 4.88's are good for 10! I have had a few of these trucks with both set ups and some with major power upgrades and got up to 12 with a F-550 with 4.88's and thats the BEST! Sure they are real power houses, but no fuel mileage at all.