AWD Towing

i would use auto mode for motorways and reasonable flat roads and let the gearbox do the work but if in hilly/mountain areas put it manual mode and use the paddles as you can hold it in a lower gear longer for up the steep parts where as in auto the box will be constantly changing up and down when the revs go up and down. if you know what i mean. not a good explanation. try both and see what you find the best.

Towed with the S-Max for a year or two. Left it in auto all the time and it pulled beautifully. Just let it do the thinking, it will adapt and should give a good driving experience. It should be one less thing you need to think about.

I use auto mode, I have a sport mode and sport mode plus but on mine this is still auto but selects a higher gear than the auto normally would. I can override with the paddles which I chiefly use going downhill to increase engine braking. If towing a heavy caravan it may be better to use sport to avoid the gearbox "hunting". Some parts of the A75 south of Clermont Ferrand where the autoroute has some steep climbs I use sport.

I don't have the option with my auto tow car, but you can use either. You'll  probably soon get bored of manually changing gear & leave in auto ...... how sporty are you going to be driving with a wobbly box on the back of your car? 😉

Doesn't the sport mode also work in automatic, just holding the gears longer and changing down sooner? Our cars are all auto with sport mode (although not Fords), and I can use the paddles in all modes, or auto in all modes. 

I would also use Auto on motorways, going up hills I would use auto, although I might put my foot down just before the hill to get it to drop a gear to keep the revs up.  The only place I would consider manual is going down hill.