Reviving this thread.
Shawn (or anyone)
Have you ever sent out oil to a lab to have a "used oil analysis" done?
They will check to see what is in your oil and might be able to point you in the right direction. Fuel dilution, metal content, etc.
Now that I have 20k on my LS1 in my GTO I am going to send in a sample next oil change and see what I got in the Mobil 1 out of that.
The test costs like $20-30 bucks.
