Maybe a loose wire or for some reason the LED bulb electrical draw is affecting the fog lamp. Try putting the factory bulb in one headlamp and check the fog lamp on the same side. If it works, LED is the problem.
If the rpm is higher than 1200 when you put it into drive then the motor is not warmed up. Do you get the same issue after driving it for awhile or is it only when cold? If it's in the teens where you live, get a remote starter and let it warm up. If it does clunking when driving after awhile...
Let the motor warm up until the RPM is down to 1,000 before putting it into gear. Then with the brake pedal still depressed leave in gear for a few seconds before lifting foot from brake to gas pedal.
I leave my bed open but in the past I had a Silverado regular cab short bed that I put a vinyl folding cover on it. I liked the look and kept using Armorial to keep it from weathering. It was very easy to either fold back or remove. Liked it a lot.
I have a 2015 double cab 4x4 auto with 5' bed 4.0L and it barely fits in my 3 car garage. If it were a 6' bed I could get it in but would have no room to get around it.
No issues after 36.000 miles other than the paint on the doors was too thin and warranty paid to re-clear coat them. Some of...
Best to take to a A/C place who can evacuate and recharge the system. The machine will clean any impurities and send the refrigerant back into the system along with new refringent to top off the system. They will also introduce dye that will help spot any leaks in the system. Money well spent...
Sounds like one of those electrical gremlins got into your truck. Hate those dang things. I would check the wiring under the dash. Could be a loose ground.
I had a similar problem with my daughter's Ford Focus. Had a rough idle and when you turn the a/c on it would worsen as the compressor put a strain on the motor. Turned out to be the transmission mount was bad. Might check motor and trans mounts also.
If it only does it at idle, possibly injectors need cleaning/flushing. Also could be a/c compressor cycling and if bad causing an extra load. If it only does it when you first put it into gear it may be transmission issue.