I've installed an oil catch can almost as soon as I purchased the car, exactly to address the issues that were brought up on the video. every little bit of prevention helps....
I am here to take back what I said. For deposits oil viscosity doesn't matter as it's not oil vapors that cause deposits rather oil mist. SN plus (LSPI protection) rating and higher PAO is very important for the oil to have.
I am going to use Mobil1 Extended Performance 5W30. It also has the A5/B5 Kia recommends.
Page 8-9 gives you the chart. Pick what fits your climate and driving. I could run 15w40, but choose Euro Spec Mobile 1 5w40. Nothing magical here. View attachment 16819
The chart is just saying that a 50 weight oil has a somewhat overlapping temperature range, but you're giving up more cold start protection by going from 5w to 20w than you're gaining in hot operation protection by going to 50 weight.
Even at 100 degrees out, your oil cooling system will keep your oil temp in its target range. If you also decide to track the car, keeping sustained high boost/revs, a 40 weight will keep from losing viscosity vs. a 30 weight.
But at startup, you're 100-150 degrees (or more) below the oil's operating temp. Every oil will be thicker than it should be, but a 0w or 5w will be less thick and get flowing more easily than a 20w. So you're trading disproportionate wear at a critical time, every time you start up, vs. slightly better protection in edge scenarios where you exceed your oil cooling capacity.
You'd be better off running one of the fancy new 0w40s.
The chart is just saying that a 50 weight oil has a somewhat overlapping temperature range, but you're giving up more cold start protection by going from 5w to 20w than you're gaining in hot operation protection by going to 50 weight.
Even at 100 degrees out, your oil cooling system will keep your oil temp in its target range. If you also decide to track the car, keeping sustained high boost/revs, a 40 weight will keep from losing viscosity vs. a 30 weight.
But at startup, you're 100-150 degrees (or more) below the oil's operating temp. Every oil will be thicker than it should be, but a 0w or 5w will be less thick and get flowing more easily than a 20w. So you're trading disproportionate wear at a critical time, every time you start up, vs. slightly better protection in edge scenarios where you exceed your oil cooling capacity.
You'd be better off running one of the fancy new 0w40s.
None of them are 0 weight, the second number is the viscosity at operating temp. The first number isn't even the viscosity when cold, it's saying when cold, the oil acts more like a 0 weight oil would at that temp.
In other words, a 0w30 oil is 30 weight at operating temp, and thicker than that below operating temp, just not quite as thick as a straight 30 weight would be. Unless you're way above operating temp, neither a 10w30, 5w30, or 0w30 will ever be thinner than 30 weight.
Even in colder Sweden most of us run 10W-40 as Stinger engine runs very hot like around +200 F or 100 C. In ECU tune we lower engine temp to around 85 C or 185 F. Dont seems so much but is is a big difference in thickness just these 15 C. Gives more room for more power and help us with the octane as lower temp dont need as high octane as high engine temp.