keithd

Long story short my wife stopped in to autozone to get a quart of oil to put in the truck. Worker told her the oil was really low and put in about 3pts more than it needed.

She drove it home and called me saying the engine sounded bad. The next morning i check it out and have no oil pressure and the engine is knocking.

In discussion with the regional manager of autozone. It seems that every mechanic I talk to states that over filling cannot damage an engine. Which goes against everything ive ever heard and read.

question is: how and what exactly can be damaged due to over filling by at least 3qts of oil?

Thanks in advanced.

JCR 56

What made your wife think the truck was low on oil, was it already knocking?

keithd

No knock. I checked it before I went out of town for work it was just below the bottom mark on the stick

Marc D

When an engine is overfilled with oil the crankshaft is immersed in the oil and it whips up air into the oil like a blender. As this air enters the oil system it loses oil pressure and stops lubricating the bearings. I doesn't take long before you get major engine damage like a rod knock.

keithd

Outstanding.

Sniperuml

Drain the oil, put the oil plug back in and let it sit overnight so the crank and valves drain completely. Hide keys so you don't try to start it. The next day replace the oil filter and refill using proper amount of oil. I have fixed this problem doing this procedure, when my girl took my old car to Jiffy Lube for an oil change. Now no one touches my cars, I do 90% of all work.