What dire problems will occure if 1/2 to 3/4 Qt of oil is overfilled in engine?

 

I typically run my oil roughly 1/2 qt overfilled to act as a little extra insurance against oil starvation when cornering on race tires, have been doing that for years with zero problems. I'd guess that you will be just fine, but as usual YMMV!
Jason

 

One problem you can encounter with overfill is oil aeration due to the crank whipping the oil. Aerated oil can lead to premature bearing failure. It also leads to excessive oil temperature. A way to check is to look for air bubbles in the oil right after you shut the engine off.

From the previous post, appears the amount in question is not an issue.

 

On page 114 of my owner's manual it states "Do not fill beyond the upper mark on the dipstick. Excess oil will damage the engine.". It happens on our R53 that 4 quarts and 24 ounces puts the oil level spot on. On one of oil changes they arbitrarily put 5 quarts in and the oil level was about a quarter inch over so I loosened the drain plug and carefully drained a small amount oil. As it turned out removing 8 ounces put the level exactly on the upper mark. I figure if I follow the manual 99% of any doubt should be removed.

 

5 quarts of oil is ok...plenty of people do this...5 qt shows it at the top mark on my dipstick...

 

If anything, you could just remove/loosen the drain plug to let a little out.

 

+1, I almost always just do 5 quarts with an oil change.
No problems.

 

+2 been doing it for tens of thousands of miles.

 

The stated volume in my manual...
If you are within a quarter or a half quart of the full line, should be fine imo.

 

I also fill with 5 quarts and it reads to the full line on my dipstick. I also drain my oil very well by getting as much oil out as possible while the car is level then I raise the front end to get the remaining oil out. If you fill with 5 quarts and it shows too much oil just drain a little out from the drain plug. I also read the oil level after It has been driven around the block and then given a chance to settle back down. I do this thinking it will fill all the normal areas like the oil filter.

 

A quart over is not going to destroy your engine. Any more than that and you'll get the egg-beater effect mentioned above.