You don’t need a pipe on your blade to plow snow on gravel. Just reverse the moldboard so the blade skims off snow without moving gravel. I’ve been doing this for over 25 years.
My Maverick was cold blooded and used oil regularly. A real POS. And the Vega engine was known to self destruct. No way they were better than any modern vehicle.
Filling rear tires does improve traction, but the primary reason for filled tires is to add ballast as a counterweight for using the loader to lift heavy loads.
I’ll have to go look at the manual again, but my Dodge/Cummins truck manual says 10 degrees or lower for conventional 10W-30 oil and -5 degrees or lower for synthetic 5W-40 oil. I would assume that it’s something similar for our tractors.
Synthetic oil at 5W-40 weight is far better than dino 15W-40 in cold weather. It’s obvious that the engine starts better and runs quieter with the synthetic.