I'd take down the antenna, pump up the tires, buy a new gerbil and make sure the body is waxed.

I had a '73 220d and asking it to pull a trailer on the highway is not something I'd do. Maybe through the backroads, but I think you'll be limited to sub-speed limit figures.

A friend pulls a 2000 pound boat with his 300SD and says it's marginal, but OK.

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1984 300Sd 210k

Former cars:
1984 300D 445k (!!) (Strider) Original (and not rebuilt) engine and transmission. Currently running on V80 ( 80% vegetable oil, 20% petroleum products). Actually not, taking a WVO break.
1993 300d 2.5 275k. Current 120/day commuter
1981 300SD 188k (Hans) Killed by a deer