I live in Chicago where the night-temperature averages in low 20-degrees-fahrenheit and last year’s (2019) record low went to 23-degrees below zero. To prepare for another (possible) year of low temperature, I replaced the engine oil in my generator and snow-blower with synthetic 5w-30 (API SN).
Questions:
- Is synthetic 5w-30 good enough or should I use synthetic 0w-30 instead?
- What is the lowest (reasonable low) temperature that synthetic 5w-30 can handle?
- Can I leave synthetic 5w-30 over summer since (theoretical) specifications say that it can be used for temperatures as high as 90-degrees-Fahrenheit
- What is the downside of synthetic 5w-30 compared to synthetic 10w-30
(BTW, my carburetor is perfectly clean and I have no problem starting at around 30-degrees-Fahrenheit)
Thanks.