Interesting info about increasing the clearances. There is something going on. What I am wondering about is the engines that make it to 20000-30000 then fail but have no issues before 5000 miles.
I still would not run 0W20 either way. Not sure your weather and traffic conditions where you live. We can have 20F (-7C) to 100F (38C) and have aweful traffic conditions where in 100F (38C) it takes 45 minutes to drive 10 miles (16kM). The crazy hot temps and heat soak after crawling in traffic and idling is not easy on the engine oil.
I assume you probably have much colder Winter temps, not sure where you Summer temps tend to top out at.
The service guys say that if the engine fails before the first oil change, it will be up to about 10 thousand km, or 6 thousand miles. These are most likely temperature gaps. On longer runs, the reason is the missing oil level. Unfortunately, our oil pressure sensor responds very late. It’s catastrophically late, and if you saw it on the dashboard, then most likely engine repair is already inevitable.
When changing oil, we always cut oil filters and examine them for the presence of metal shavings. This is also a form of diagnosis. If there are chips, then open the engine.
As for the conditions, they are closer to the conditions of Canada, we have -40C in winter and +40C in summer, our driving conditions are good, in a metropolis like Moscow, the average speed is about 30-35 km/h, which is about 20 miles per hour. And the presence of high-speed highways allows you to cover the distance between cities of 700 km in 4.5-5 hours.
I will mention another important point regarding the oil level, we discussed this in this forum. The GM manual indicates an oil volume of 8 quarts, which is equal to 7.6 liters, but in fact, if you add 8 quarts when changing the oil, the oil level will be at the middle level on the dipstick. To get the Max level on the dipstick, you need to add almost 1 more quart, or 0.7 liters. In Russia, when changing engine oil, we pour approximately 8.2-8.3 liters of engine oil to the Max level.
This means that we have a better chance of preventing the engine from starving of oil. So yeah, since we don't have GM's support, we have to get out and monitor the car more closely. For example, I check the oil level once a week, or every 1000 km. Even if I’m on a long trip, involving a mileage of more than 1000 km, I stop at a gas station and while I drink coffee I allow the oil to drain into the crankcase, and check the oil level.