- Joined
- Mar 28, 2021
- Messages
- 6
I recently learned about the blotter spot test for evaluating oil for quality. This sample is from my 2000 Z71 5.3 that is driven maybe 2000 miles per year with short 10 to 15 mile trips to town. Even less than that over the past year. I think the oil is 3 years old. It is Mobil one 5w 30 synthetic. I know it is less than 5000 miles old due to the oil light not coming on.
Anyway my evaluation of this test is the oil needs changing. There is the darker center dot with a defined ring around it. So the oil has oxidized and the dispersants are not working well. There is also the outer ring around the center indicating some fuel in the oil. The sample was taken after a 50 minute drive on the highway. The sample is 48 hours old. I did change the oil and will keep track of miles and time.
Sample with back lighting
Sample without back lighting
This is a 72 hour sample from my 18 Camry 2.5 with 7200 miles on its oil of daily driving of less than 20 miles. 0w 20 Mobil one. This oil is in good shape no center ring or dark areas. There is some fuel dilution. Probably due to it being dual injection and the short trips This sample was taken after a 10 mile trip with 18 mins drive time.
Camry sample with back light
Camry sample without back light
Anyway my evaluation of this test is the oil needs changing. There is the darker center dot with a defined ring around it. So the oil has oxidized and the dispersants are not working well. There is also the outer ring around the center indicating some fuel in the oil. The sample was taken after a 50 minute drive on the highway. The sample is 48 hours old. I did change the oil and will keep track of miles and time.
Sample with back lighting
Sample without back lighting
This is a 72 hour sample from my 18 Camry 2.5 with 7200 miles on its oil of daily driving of less than 20 miles. 0w 20 Mobil one. This oil is in good shape no center ring or dark areas. There is some fuel dilution. Probably due to it being dual injection and the short trips This sample was taken after a 10 mile trip with 18 mins drive time.
Camry sample with back light
Camry sample without back light