I can't speak to the cooler though I think it's probably a good idea. I towed my Ski Nautique (about 3500lbs) with my 2012 V6 4 times a week for a year without issues. The V8 is better, but the V6 was fine.
2014 Crystal Granite Overland 4X4, Hemi, QDII, Advanced Technology Package, 20" Wheels.
2012 Laredo (Traded on 2014 Overland)
1997 Laredo (Traded on 2004 Touareg)
1989 Limited (Traded on 1997 Laredo)