Filter
Top Products
Overfilling
This is an unfortunate reality that far too much owners have to face. Oil pumped from bulk barrels
into your engine is commonly not carefully measured by dealers and quick oil-change places. So
make sure to check the level yourself after the service is complete. If the oil-level is beyond "full",
insist that they remove the excess.
The ideal level is 1/4” (one-quarter inch or 6 millimeters) below the "full" mark, which is between
the D and the E on the photo above.
Too much oil causes MPG to be reduced. Way too much oil causes damage to the engine. So it is
in your best interest to make sure the oil-level never goes above the "full" marker on the dipstick.
3.9 quarts (3.7 liters) is the maximum capacity, so there is no need to ever use that much. Never
pour in more than 3.5 quarts (3.3 liters). Even less is better. It's easy to add more afterward.
Removing too much is very, very difficult.
A simple way to avoid overfilling problems is to provide your own oil (which is common for those
preferring synthetic anyway) instead. They'll just deduct the price difference from your bill. Only
supplying the mechanic with the correct amount will guarantee they won't overfill.
Prius User-Guide 24 of 45 Last Updated: 2/07/2006