I have an older Buick 215 with 150k miles. It's the V8 version of the ubiquitous 3800 V6. Traditionally, it would have called for 10W-40 or 10W-30 in my climate, but I've been using 5W-30 for better lubrication when starting it in the winter. It's parked outside and while it's rarely below 0 deg. F, startups were noisier with 10W. Years ago, I tried the 0W-40 that I use in my two other cars but it made too much valvetrain noise. I do a lot of short trips so the oil doesn't come up to temperature. The 5W-30 would only very rarely result in a lifter ticking.
I just filled it up with 5W-20 Mobil 1 High-Mileage. I bought the wrong weight by accident but had filled it before I knew. It should be no issue through the winter, but I typically put 5000 miles a year on this engine so the oil will only have a couple thousand miles on it before summer and 90 deg. F. I suppose I'll just wait and see if I get valvetrain noise on hot days and change it out if I do. Or should I change it out at the end of Spring?
I know what happens if I go to low viscosity in the first W-number -- with 0W I get lifter noise until the oil is hot. I'm not sure I understand what will happen if I run a low-viscosity in the second number -- 20 weight -- in hotter weather like 90 deg. F. The thermostat is 190 deg. F and on some hot days on steep grades or with low air-flow, the coolant temperature gets to 212 F on a digital gauge.
I just filled it up with 5W-20 Mobil 1 High-Mileage. I bought the wrong weight by accident but had filled it before I knew. It should be no issue through the winter, but I typically put 5000 miles a year on this engine so the oil will only have a couple thousand miles on it before summer and 90 deg. F. I suppose I'll just wait and see if I get valvetrain noise on hot days and change it out if I do. Or should I change it out at the end of Spring?
I know what happens if I go to low viscosity in the first W-number -- with 0W I get lifter noise until the oil is hot. I'm not sure I understand what will happen if I run a low-viscosity in the second number -- 20 weight -- in hotter weather like 90 deg. F. The thermostat is 190 deg. F and on some hot days on steep grades or with low air-flow, the coolant temperature gets to 212 F on a digital gauge.