What would you do?

I have ultragauge.

Watching the temps....it starts going up, 210-220...I step on the gas and it drops to 194. While driving it seems to do fine, when your at a red light, it climbs.

I have already cleaned, flushed the radiator. No leaks.

Thermostat is about a year old, but is the normal stat not the 180°, I'm still running dexcool, and am thinking about changing it to green.

New reservoir bottle, new plastic coolant lines, new TBS heater.

I am going to check my electric fans, also the fan clutch and replace the cap for the reservoir bottle.

 

With the truck off, if your key is in the on position and the a/c is on, you should hear your electric fan on. When you say step on the gas and the temp drops, is that in neutral at a light? If so, something is restricting the flow or the impeller is worn in the water pump?

Otherwise, definitely change from dexcool to the green and get an OEM Land Rover 180º t-stat.

 

I'd start with the fan clutch. Test it - should move with a bit of tension when cold, then be harder to move when hot. If it moves easily it's toast.

Although I would swap out the dexcool and lower thermo asap, I don't think it's your problem (yet).

 

If the fan clutch was bad enough to cause what he's describing, I don't think stepping on the gas would fix it. Thinking H2O pump as well, but either way, the Dexcool needs to be swapped out and a temp test done on the radiator. I've heard Buzz say it enough times that I can pretty much quote, measure top to bottom of radiator (get the car up to operating temp then turn off and measure). If there's a 10F difference, there's a clog and you'll need a new radiator since the plastic innards of these things can't usually be piped.