I have the vauxhall antara, all but the same as the captiva.
i had a discovery td5 gs auto (facelift) for three years and had no issues whatsoever.
last year i changed it for a vauxhall antara cdtis auto.
i can put my hand on heart and say that although i loved the disco, i have no regrets at all with the antara, and thats in all aspects.
a very under rated towcar imho. certainly more stable than the disco.
320nm @ 2000rpm
150bhp
1967kg mass in service kerbweight
1700kg max tow (87%) 2000kg for the manual
80kg nose weight
self leveling rear suspension
manual selection on auto gearbox (5 gears)
as for the auto reducing the max tow i am not concerned as the tow limit is more than enough fo most.
i have contacted vauxhall in the past regarding this and the fitment of an additional cooler, they have no reported concerns.
mat