keep in mind that the mercedes motor is pretty much a detroit 60 series
DC bought up detroit diesel a few yrs ago now
found this out when i was pricing and building a freightliner m2
and was flopping on putting a detroit 60 or a MB engine in it
sales man grabbed 2 brochures and said now whats the difference besides the valve cover

I don't have a big trailer now but I get 18.5/19 town and country with my open car trailer and 41 Willys aboard. About 5000 #'s. Don't even know it's back there.

Son's "Burb" gets 10 on a good day pulling the same thing.

Towing 20' goose neck with a couple of horses, total weight around 11000lbs getting about 14mpg. My truck only has 3500kms on it hope to see some improvement when I get some more kms on her.

with my 6 spd, running at about 70-75 mph, and my car trailer and jeep (about 6500 lbs) I get about 14.5 mpg.
Scott

I get about 12 to 13 with 28' nomad weight is 8360 dry and I ran 315 bfg's

God to have a manual!

I average about 10 if I stay on the highway, problem is I never get a long enough stretch to do it (alot of stop/turn/stop/turn/stop/go/etc.). And I'm sure the 3.54s don't help in that situtation either. Tend to come across the scales b/w 22k and 27k loaded and around 12,750lbs. empty with my stock trailer.

With the amount of towing I do, Im starting to wish I had an auto.. I just love the punch it and GO! Rowing through the gears can get a bit old sometimes.
Scott

MPG's
 

Funny, i tow a 3500 lb Boat from Orlando to tampa often with my 7.3 powerstroke Dually and my last run was 23.6mpg doing 75mph, my other car (4 banger) got 25, so i guess i am doing pretty good!:ok1:

Damn right you are!!!!

I get about 16 unloaded around town and on the interstate.

This past weekend i got about 11mpg pulling a 10K lb camper between 65-70mph on US Hwy 280 between I-85 and Birmingham, AL. It's a pretty hilly stretch of hwy and some of them are rather steep...guessing 10% grades or more? I was able to keep it in 6th gear on all the hills...would loose speed but never enough to have to down shift. had her pushed to the floor alot!!! Really need to get me some gauges so i know how high my EGT's are getting

MPG's
 

We left Washington state on a vacation pulling a 29 foot 5th wheel camp trailer all the way to Michigan. The Ford 6.0 only had 800 miles on it and I averaged 15-19 mpg. Cruise does help. Now at 59000 miles, I'm getting 19-22 mpg.