Toyota Tacoma 4 cylinder

Your engine will handle the load and the automatic transmission will be fine if you don't abuse it (don't let it hunt between gears). My '89 Mazda 4-cylinder 2.6FI 5-speed used to tow a boat or fiberglass trailer for most of the 16 years I owned it without any engine issues. The trailer was under 3000 lbs and was towed all over the southern Appalachians, but the boat was 4000 lbs and typically towed over the Cascades. Stevens Pass was at 35 mph and Snoqualmie Pass was at 40 mph through the steepest parts of the climbs. I always drove by the tachometer when working an engine, followed by engine temperature and speed was what it was.