I did this exact thing and I have the same results. I bought mine from Lucky8 for $79 shipped.

 

might want to try letting some air out.

 

Whatever you do....Do not buy this one! The one right here in this link thats been posted many, many times here in threads to buy!! lol

Actually this one is working fine for me so far....

 

Those Motorads are notorious for quality control issues. I'm a cheap bastard and even I'd steer clear of them.

From the RAVE - the stock thermo is fully open at 204* F.

 

Bought a Motorad 439-180. Tstat that was pictured grey, what arrived was whitish.
I contacted the seller and they said it was the same.
I tested the opening temp and it was opening around 178F and fully open at 180F.

Installed it and have watched temps using my ELM 327 OBD2 fob and Dash Command app (highly recommend this combo).
Prio to install, highway temps were 200-208F, in town hovered around 210-220F.
Post install, highway temps are 185-195F, in town are 195-200F.
BIG improvement.
Fuel mileage has also seemed to increase a mpg or two.
This tank of mixed driving, towing, and quite of few hills netted 14.04mpgs.
I've only run one tank through this rig so far since the rebuild so not much to A-B.
More comparison to come I guess.
Recommend the 180F tstat!
Thanks guys!

 

I'm going to order the LR 180 T-stat myself, I also need an Ultra Gauge!

Before I installed the Motorad 180 t-stat, I would get a lot of radiant heat coming in the cabin from under and around the console (you would need to run the AC when ambient temps were only 70 degrees out to be comfortable) Well, that went away with the new thermo, but I noticed heat again the other day (just on one road trip), the motorad maybe sticking? so I am changing it out to a genuine one very soon....

 

I have noticed that ambient temps have a huge effect on center console temps.

It's weird.

So I wouldn't read too much into that.

I have read a few people having issues with the Motorad thermo, so it's probly smart to swap it. One thing I would not skimp on is the cooling system in these trucks.

 

So what is the main complaint or issues with the Motorad thermostat? Reason I ask is this (not to hijack thread)

My Rover ran around 188 and might get to 200 when I first bought it. Previous owner had already done HG work and had also changed to green coolant at that time. It did not have the grey thermostat in it so I kind of assumed it was just the factory 190. I actually had ordered the Motorad about a year ago just to have it if I did get into issues. Well earlier this year I started to notice a loss in coolant and still had the old bleeder screw setup that was leaking. While replacing that I went ahead and replaced the themostat. To my surprise my normal temps were up but just a little to about 194/197 on avg driving. When the summer got here I noticed it starting to get to 210 if idle long enough with or without ac and even had one instance of it getting to 225 when idle.

That all being said my radiator actually appears that it has been replaced and with and IR thermometer I see pretty even temps on it top to bottom while being just a little hotter in the center of it then the left and right but I attribute that to the viscous fan. The Viscous fan does seem ok as in when warmed up will only spin about 1/4 turn on its own. Condenser fan I replaced last year and it working and both fans blowing the right way. System seems bled properly with no air in it but I cant speak for the water pump other than it doesnt leak

All that being said when I measure the coolant hoses the two on top the thermostat will read over 200 while the bottom is 180 or so. I would expect them to be a little more even at that temp if the thermostat was fully open. I was going to go ahead and order a new genuine 180 stat but curious if my symptoms seems to point to a stick maybe not fully opening stat?