Personally, I wouldn't run that heavy a synthetic in Winterpeg unless the oil galleries were all tapped and threaded plugs installed...I've had the original frost plug style blow right out on the driveway(thankfully) during a regular winter start-up in warmer weather than you get out west...
Just saying...5W30 syn is plenty...IMHO
    On Friday, November 9, 2018, 2:53:01 p.m. EST, Jeff Palmer <w.jeff.palmer@ICLOUD.COM> wrote:  
 
 Hi - trying to get one last oil change in before parking the van for the winter. 2.1 litre engine rebuilt about 30k km ago. Normally I use 20W/50 in the summer and I “believe” my mechanic has been using 15W/40 synthetic. I can only find diesel 15W/40 synthetic at my FLAPS. This is not the same, is it? Is this the right weight of oil for me?

Thanks 
Jeff in Winnipeg

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