I have a 96 Astro 4.3L 2WD that I will be using to haul two ATVs. With trailer, I estimate I'll be towing 2500#. The manual lists a max tow weight of 4500# but I am certain that is with a tow package that mine does not have. Other than adding a cooler for the transmission, is there anythng else I should be doing to protect the engine and transmission? The vehicle has 123,000 miles and has been well maintained up to this point. The transmission fluid and filter were recently changed but the shop refused to purge the tranny because they claimed it would dislodge particles that would cause valves to stick. Anything else?

We used to have an '88 and '92 AWD versions and towed a popup camping trailer and a small 16' travel trailer and never had a problem. Also towed a 84 Nissan 4X4 back from Arkansas and had no concerns there either. Two ATVs and a small trailer shouldn't be any issue!