Does oil consumption/proper oil grade show up on an analysis?

[Dr. T]

Say a car is consuming 1 qt. every 800 mi. and the owner keeps topping up with new/fresh oil. If an analysis is done after say, 7-8k mi., will anything be different from a car in which the owner doesn't have to add a drop? Likewise, if someone was using the "incorrect grade" eg. a 10-40 instead of a 5-20...how would this show up on an oil analysis?

 

[Rick]

Yes, there would be a difference. If you keep adding fresh oil to the mix then the contaminents would be less.

 

[Patman]

If someone is using the incorrect grade it would show up in the viscosity at 100c (or SUS at 212F), but this is also misleading as it could be the correct grade oil when it went in the car and simply sheared back to a thinner oil by the time the sample was taken. [ February 07, 2003, 08:00 PM: Message edited by: Patman ]