Fuel Econony - 1999 E300D
 

Today was the first true "highway" usage of my E300 to check the fuel economy. I made a round trip between Bryan, OH and South Bend, IN. on the Ohio and Indiana turnpikes. There was about 45 of 247.1 miles that was combined "city" and two lane state routes. I filled up this afternoon and calculated 29.1mpg. This this common? I was hoping that it might achieve closer to 32/33.
Thanks,

Sound about right. Your sig says you are running B100 that will cost you a few mpg's.

You need to average over a few trips low 30's seems about right on these cars for easy highway work.

I would have to drop freeway speed below 70mph to get 32-33 mpg. Most people are over optimistic in regards to fuel economy, yours seems about right considering everything. If you want to approach 35 mpg I suspect you would have to set the cruise at 60 mph and just crawl along the freeway, which is a bit dangerous in a lot of places.
Best Regards,
Paul
__________
98 E300

As far as the B100 I have not used any since late October because of the temperatures in the northwest corner of Ohio. I miss using it. I hope to start back in April.

The trip today was with a fellow engineer. All of the company vans were signed out so we took Emily to South Bend. I let my co-worker drive back....it damaged his GM only thinking. All he talk about was the car.

Winterized diesel would also account for some of this. Half tank is not the most accurate either. I have not checked mine lately, but it seems like it is averaging just under 30, mixed city, rural and some longer runs at 65 - 70 mph.

Is all the general maintenance good? Synthetic oil, tranny fluid, rear diff, tire pressures (mine are about 40psi), filters (air, gas - pre & main), would like to think with the miles you have you should not have problems with wheel bearings, yet.

Oh, in weather like this do you have the A/C off? Basically it is always on unless it is in Economy mode, that would account for a couple mpg there.

Yes the winter diesel mix has a few less BTY's than the summer mix. You have less power from each gallon, hence the MPG's will drop slightly. Adding some cetane booster may extract a little more power out due to the better burn characteristics, but they may not really be noticed.

Over lunch I checked the mileage on mine. This is nearly 2 months of winter driving, complete mix of driving from short trips, idling, medium trips at 65mph and longer trip at 75 mph.

937 miles on 32.8 gallons = about 28.6 mpg

I consistently get over 30 (and usually over 31) overall MPG with my NA '96, but we're still on #2-d here. Overall for me is about 90-95% highway, usually at about 75 mph.