Many T/C autos are fitted from new with a cooler-have a look.There'll be pipes from the transmissiom to the radiator or to a seperate cooler.

Thanks chaps. You have put my mind at rest. I did think that offering a fully wired tow bar as an option did indicate the manufacturers are confident that the vehicle will tow safely within it's limits without undue stress. The towing weight of my caravan is at least 300/400kg less than the maximum allowed for my vehicle. I will have a look underneath too, just to see what is there. The caravan club are of the same opinion, that a TC autobox on a properly constructed vehicle fit for purpose is the best for towing. It apparently makes decisions about correcting towing stress with gear selection a lot faster than I could.

Cheers Concrete

Some years back I had a Subaru Outback automatic - on an Outback specialist forum one one the contributors worked under contract for Subaru on their automatic transmissions - his unequivocal recommendation was to leave the transmission in Drive rather than "tiptronic"/manual mode as the transmission ECU would protect both the transmission and engine better.

Some manufacturers, when building a car at the factory with an optional towbar, also fit extra gearbox oil cooling capacity - which is why some OE optioned towbars seem very expensive.

Some maufacturers also carry out engineering tests of vehicles out in Nevada and Death Valley with fully laden vehicles towing laden trailers. The vehicle has to cope with seering temperatures, often on inclines with aircon going full belt too.

Whether either is the case with the XC60 I do not know - try asking the dealer

The Americans introduced the SAE J2807 towing test for pick-ups to normalise the extravagant claims being made by truck makers - it's known as the "Davis Dam Grade" test, 11.4 miles of 5% at temperatures OVER 100 F and includes multiple restarts both forwards and reversing.