Thanks to all!
As a newbie, I really need to express my gratitude to all the replies I received. You managed to alleviate my fears, and the links have been helpful. To answer your queries, the Merc handbook lists my car's max. braked towing weight as 1900kg, and the MPLTM of my caravan is 1534kg, so it's well within that. My previous Audi was the V6 2.5 TDi, so the weight of the engine meant it handled the caravan well enough. Since so many of you believe that towing up the French Alps in a hot summer would be my only time to be concerned, I'll remember that when we finally get to move and make our home there as we plan! Then again, I'll be buying a LHD once in France. Having long been an Audi afficionado, I'm now unsure what I'll buy next. If I can have a good Merc TD estate as well as an RS4, I'll be happy! My car has no separate oil cooler in front of the radiator, as this is for the aircon one. However, yesterday, I had to go to an MB breaker for a new aircon pump (the comp. clutch is missing on mine!), and he assured me in an instant that my 98 model has the cooling coil within the main radiator, and literally laughed at the idea of upgrading. Again, thanks. I'm sure I'll be posting again at some time.