I also looked up in the online Microcat (lrparts.ru, use english version). It showed the thermosat was same for LR3 and LR4, pn LR005765 (4.4 liter petrol). Now I would be the first to agree that LR4 may be running at 220, but somehow that just isn't making sense. Just like a D2 can run at 227F, and still show normal. May be "in the range" but does not seem optimal to me. Seems like the purpose of thermostat is to control how cold the engine will stay during normal operation, and slow down water thru the radiator so it can cool off. Once you are way past wide open temp, the thermostat has no control, and is a useless orifice. That said we have guys who have posted on here about towing a trailer in the desert at 109F outside, 195 coolant, with the 180F stat in a D2. Without trailer they make under 190F.

 

The lr4 has a 5L engine.

 

The LR4 has a direct injection 5.0 engine, its normal operating temp is 220*F.
It needs to be hot to combust the fuel properly and to keep the oil clean, as well as the fuel injectors, oil change intervals are 15,000 miles or once a year.
The thermostat holds the coolant in the block to warm up the engine, once the engine reaches normal temp then the t-stat is useless, the radiator and fans cool the engine, not the t-stat.
The restriction of the t-stat just being there is enough to slow the flow of coolant enough to allow it to stay in the radiator long enough to be cooled.
Thats why drilling extra holes into a t-stat that does not already have them is a bad idea.

 

Too dependent on computers.

 

So how would this work in say Grand Rapids, on the freeway, in January, with wind chill that can take paint off? Once warmed up, I can understand how fans can come on to keep heat down. But at freeway speed you don't even need a fan, the 5280 feet per minute of air flow way exceeds the fan. So in the grip of winter, how would you stay at 220F on the freeway with a 190-203 thermostat? I'm not sayin' it does not work exactly this way, I'd justy like to know more.

 

Its a hotter t-stat.
The BMW engined RR's t-stat is electronic, at full throttle it goes wide open and opens all heater hoses too.
The Jag engined RR runs at a different temp.
The Ford engined LR3, different temo.
Jag engined LR3...
Jag engined LR4...
The 5.0 LR4...
The t-stats temp will depend on the application.

 

Well then you should start a fruit jar (redneck piggy bank) to buy one because I know how much you like good heat in the winter!

 

In the winter the coolant in the radiator does not get cooled off to zero.
The radiator displaces the same amount of heat summer or winter. It just takes longer to heat up in the winter.