In January to March 2018 I made an overland trip from Magadan to Moscow, trying as much as possible to stick to winter roads / ice roads / frozen rivers etc. That went through some seriously cold places, though there was a bit of a (relatively speaking) warm spell and I didn't get temperatures any lower than about -45°C. You can read a quick trip report on this great site:

https://www.horizonsunlimited.com/hu...n-kolyma-95144

My car was petrol and a Toyota, so I don't have experience with diesel gelling or how a Land Rover might behave in serious cold. Felicity Aston did a similar Russia trip with Land Rovers and told me most of the expedition's problems were down to the vehicle(s). But they got temperatures down to -50°C which is frankly too cold for diesels.

In my experience, a temperature of around -25°C is the lower limit of vehicle design for cold, below which extra preparations are useful. I blanked off the radiator almost completely below this temperature, ran an engine blanket and double windscreens to prevent icing (all common winter stuff in the coldest parts of Russia). If I was camping out in the wild below -30°C I would keep the engine running overnight, with a CO alarm in the car. The vehicle's own heater worked fine (with the engine on of course) down to about -30°C; below that I had an air heater running in the cabin (which I had put extra insulation in). Obviously, with the engine off, the air heater was on all the time. I'm not familiar with the Nordic winter but I feel like it won't go below -25°C for long periods.

So, your preparations sound good to me; I ran with fully synthetic transmission and driveline oils (75W-90) and had no issues. Below -40°C I could feel the DOT5 brake fluid start to stiffen in the brake and clutch, but didn't have issues. I ran a 2:1 coolant which was good down to something like -57°C. I had AGM starter (under the bonnet) and leisure (in the cabin) batteries on a split charge system, no issues with that. In the engine I ran Petro Canada 0W-20 and noticed no change in (usually zero) oil consumption or noise in the engine. I would be careful with blocking your radiator unless it is very cold - just make sure your thermostat works. Also, the coolant type heater may not be great for keeping warm with the engine off, as it will require running (I imagine) the vehicle's main/starter battery to power the heater fan. Camping in those temperatures without heating would IMO be miserable and frankly unhygienic.

Happy to discuss further.

EO

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EurasiaOverland a memoir of one quarter of a million kilometres by road through all of the Former USSR, Western and Southern Asia.