Howdy! My name is Moe. I'm new to the forum. I have a 2006 H3 with the 3.5L engine with 206,000 miles. I'm having problems with the transmission downshifting into 3rd gear and not wanting to shift back into 4th. The engine temp has never ran over halfway on the gauge. It typically runs below halfway. While driving over 55 mph and under a load, the temp slowly climbs to a fraction above halfway and the transmission will downshift into 3rd and will not shift into 4th until the temp falls to halfway on the gauge. At 65 mph the engine rpm is around 3100 and if I continue to drive it at 3100, the temp will come back to halfway on the temp gauge and the transmission will shift back into 4th. The engine never overheats. The temp only climbs going up an incline. I didn't like driving it at 3100 rpm but I was trying to get a better idea of what was going on. The codes I have are 449, 365, 366, 016, 017, and sometimes 894 and 742. The engine has just started not wanting to start and I'm assuming that is the camshaft sensors or the crankshaft sensor. The water pump and fan clutch was replaced about a month or 2 before the shift problems occurred and I had not had it above 55 mph. Was going out of town and on a 70 mph road when it downshifted and started acting up. It did use some coolant but I figured that was because there was air in the system after the water pump replacement. It hasn't used any coolant since I topped it off around 800 miles ago. Any help will be greatly appreciated. Thanks