BMW of course will want to sell you their version of AUS32, or Aqueous Urea Solution, 32.5%.... for 10 times what you can get it for in a truck stop or auto parts store.

Look for posts from Cdnrockies (i think). He live in cold. Like minus 30 cold. Some issues with very, very cold- but nothing you'd see here in most of the USA, IMO

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