Towing Experience with my E300
 

A recent move from Key West to north Florida gave me an opportunity to do some towing with my diesel. I had a custom class II hitch installed which is barely visible from the rear when the ball and connector are removed. I rented a small 5X8 UHaul and towed it with about 1000 lbs of belongings inside the trailer.

My observations are favorable with one exception. My usual fuel consumption on the highway at 70 mph is about 32 mpg . Towing brought that down to 19 mpg when towing at speeds of 65-70 mph. I had hoped to get about 25 mpg based on my previous towing experience in an 83 300D which would tow the same load and get 19 mpg. Needless to say, I'm a little disappointed in the fuel economy numbers as compared to the W123 numbers.

Handling and perfomance were excellent. Acceleration was still good with the turbo kicking in at 2000-2500 rpm range and cruising at 70 mph with the cruise control was no problem. Of course we have no long hills down here so I don't know how it would fare up a long, steep grade. I suspect it would do well based on the small hills I drove through in central Florida. The speedometer stayed pegged at the set speed with the cruise control engaged. Engine temps were about 5 degrees above normal at 85 C. OAT were between 90-95 F during most of the 800 mile trip.

I was able to compare all of this to my wife's ML320 towing the same trailer with about 300 lbs more weight. The ML320 usually gets about 20-22 mpg on road trips and got 17 mpg towing the 5X8 UHaul trailer. Pretty impressive when compared to the diesel's 30% reduction in fuel consumption when towing.

I think aerodynamics really hurt the E300 and had minimal effect on the ML320 since it sits about at the same height as the trailer.

Hope this info is useful to those of you who are thinking of getting a hitch on your W210 diesel.

I would rather state that the gas guzzling ML320 is sucking fuel at a rate of 21 mpg for every mile that I drive and the trailer reduced that to 17 mpg. The fuel efficient and aerodynamic E300 gets 32 mpg and the trailer reduced this to 19 mpg for the one trip with the trailer attached

21 mpg is hardly impressive. Dropping to 17 mpg would not make me feel any better. :(

I get about 24mpg without my trailer, 17mpg with it. I don't know how much it weighed but it included climbing mountains and I think its quite an aero load. I remember my diesel did better but I don't remember the numbers.

I would agree the aero load on the sedan due to the shape of the trailer is a likely source of the added fuel consumption. I drove from CT to TN recently to pick up a jet ski with the 240D. This car has about 320,000 miles on it and runs pretty strong. We got 32 mpg on the way down, without a trailer. We picked up the jet ski and its trailor there, total wt. of about 900 lbs, and got 28.5 mpg on the way back. The jet ski was pretty low and tightly tucked in behind the car, so I think the aero effect was minimized. In addtion, in deference to the car's age and mileage, and tendency to spew oil at high speeds, we drove under 70 mph the whole way down and back, with the way back generally held to 65 mph. I was pleasantly surprised. Getting about the same result driving it from CT to Upstate NY (Willsboro on Lake Champlain), which includes some good, long, steep hills on the Northway. Jim