Ozoning the 2014 GMC Sierra 1500 I picked up on Wednesday. It's definitely helped get rid of the cigarette smoke smell. Hopefully replacing the cabin air filter and scrubbing every surface/cleaning the carpet will do the rest.
Mine was doing that recently so I decided to change the filter/gasket. Turns out my pan bolts were loose as heck (not sure why...). Hopefully you have the same problem.
I use a 1-7\16" wrench for the nut and check out the fan clutch holding tool from advanced auto. Mine comes off easily though. Also, if you unbolt your fan clutch from the fan you can maneuver the whole assembly out easily around the radiator neck. Just make sure to put a cardboard piece between...
That glass boat your towing is definitely heavier than my aluminum! Lately I've been considering switching to a glass hull to minimize pounding in heavy waves on the Columbia River\ocean.
My temp doesn't seem to change much when towing around 2000 lbs with the AC on, even when going up a grade. Of course, it's rarely above 85 out here in Western Oregon, so don't know how much of a factor that is. My gut feeling is that you have a cooling system component issue...
Are you conjecturing that another PCM reset would cause the excessive fuel consumption to cease until the underlying problem caused it to again command higher fuel usage? That would be an interesting and easy test to run.
Also, I was thinking this issue is worthy of an ishikawa (fishbone)...
I miss that firebird sometimes. Bought it for like $3k, and sold it for 4k. I had the 350 also, rebuilt it at the base auto hobby shop, and promptly got shipped overseas...