I'm considering a road trip up to Alaska (from Utah) next winter. By then my Audi 100 quattro should be converted to a freshly rebuilt turbo diesel. I have collected four pages worth of notes on what to bring, preparations to be made, maintenance to be done before leaving, etc. Does anyone here have any real world advice on when to travel this road? I would like to go when there's plenty of snow, but not blizzards, massive snow drifts, or -50 degree temperatures. Would early winter be better (i.e. October), or late winter (i.e. March)? I'm pretty flexible here. I don't have any specific time or place I need to be. I'm just doing it for the experience.
How about running a diesel in ultra cold weather? I went to West Yellowstone last winter in my ML320 CDI where the temps got down to -20 F, and didn't have any trouble. I'm considering insulating the fuel tank, fuel lines and battery box on my Audi. Is this overkill? Any recommendations on fuel additives? Can I just leave the car idling all night to keep heat in the engine? I heard about some problem doing this because combustion temps start to drop and moisture starts to build up in the engine? I'm also considering running heat from the surface of the exhaust manifold back into the intake. Good idea?
Thanks for any advice.
I drove my bunny to wisconsin in January '07. It was cold.

I slept in my car, starting it from time to time during to night so it wouldn't freeze solid. One night I mustuv not heard my 'time to start the car' alarm and it wouldn't start the next morning. I think it was around -25F.
I made sure to always spend the night in civilzation just in case of that. I always heard canadians were nice people and one guy proved it that morning

Towed me into his shop and plugged it in for an hour or so

.
Take enough warm gear to stay alive at -40, I don't know how cold it get's in october but I rode (I wasn't the driver) from Idaho to Alaska in February.....in a caravan......how boring

. Anyways in February it was pretty warm, I don't think it ever got down to 0F.
Also there are a lot of areas of nothing, so you don't want to skip filling up, 'because you probly have enough 'til the next town'. I did that and didn't quite run out but when I did fill up I managed to fit 11.4 gallons in the 11 gallon tank

.
I don't remember adding anything to the diesel fuel but it was never an issue. Have fun
buy some of this for sure.. it has superior anti-gelling supplements and adds 4-5 Cetane numbers.
Winter Performance Benefits:
* Prevents fuel gelling in temperatures as low as -40°F.
* Equals the performance of a 50/50 blend of No. 2 and No. 1 diesel fuels
* Lowers Cold-Filter Plugging Point (CFPP) as much as 36°F. — keeps fuel-filters from plugging with wax
* Boosts cetane up to 4 numbers for faster cold starts
* Contains anti-icing additives — protects against fuel-filter icing
Year-Around Performance Benefits:
* Ultra Low Sulfur Diesel (ULSD) Compliant — contains less than 15 parts per million (ppm) sulfur
* Effective in all diesel fuels, including ULSD and biodiesel blends containing up to 20% biodiesel (B20)
* Contains Slickdiesel® for maximum fuel lubrication — protects fuel injectors and pumps against accelerated wear from Low and Ultra Low Sulfur Diesel (ULSD) fuels
* Boosts cetane up to 4 numbers — engines run smoother with less power lag
* Boosts power — reduces need for downshifting
* Keeps fuel injectors clean — exceeds Cummins L10 Injector Depositing Test Superior specifications
* Increases MPG — fuel savings exceed cost of additive
* Disperses water in diesel fuel
Clean and inspect all of your battery terminal connections.
Regrease and inspect your starter.
Think about putting a lighter weight oil in.
If you have one, make sure your block heater works.
Make sure your alternator is charging well.
Cold start cable is in good condition and works well.
I think the heat back to the intake idea is a bit overkill for the amount of time it would take to do. The problem you will run into with cold temperatures is going to be having trouble getting it started. Once started it will run fine. Anything else that you can think of starting related check and make sure it works properly!
Have fun!