So over the last 2 years my 4runner hasn't been getting as much love/use as it used to, but I still drive it about twice a week. A little over 2 years ago I did the TB, Water pump, valve cover gaskets and belts, all with OEM parts. I used to run a scangauge on it all the time and the coolant was pretty much ALWAYS 192-196, it barely moved at all once it got up to temp, but i stopped running it before I did all of this maintenance. So last summer I used an OBD 2 scanner and app and found out that on my trip up to North Carolina, my temps on the highway were running maybe 215-230 towing a trailer. Pretty concerning. After that I wasn't driving much more than a couple mile trips around town. A couple months ago I added a Scangauge again to keep a constant eye on the temps.

This past weekend I dug into things on the runner to fix my squeaky AC belt, but in a new battery and a CS144 alternator. I went ahead and replaced the thermostat (even though this one wasn't very old) and made sure the jiggle valve was at 6 O'clock (I was thinking maybe I had it installed upside down, turns out it was installed correctly at 6 o'clock). In doing this I also replaced a lot of coolant, which was nice and red. I burped out a bit of air as well, but once the initial air burped from filling up the coolant, no more bubbles in the filler tube. Turns out my Radiator cap was broken, so I replaced with with one from Advanced Auto. At this point I figured that was the culprit.

Things are better, but still running hotter than what I think should be normal. At no point does the needle on the gauge on the dash seem to move about half way, but that thing seems pretty worthless. Temps will get up to about 219 but once I'm at highway speeds they slowly start to drop back down to about 205. I'm thinking the fan clutch might be a culprit at low speeds but driving 70 down the interstate it should be cooling back down to the 190s. Am I crazy?

***Edit*** I am remembering that last spring I would have the coolant boil in the reservoir on my way home (up a small mountain) but I think that was because of the bad radiator cap causing loss of pressure and thus a lower boiling point for the coolant.