We all know that too little oil in yourcauses big problems. But even having a lot is a potential disaster. Although it may be less common, it can similarly cause catastrophic damage.
With too much oil in your engine, the oil level in the oil sump is so high that some of the moving parts in the engine block, especially the crankshaft cams and the connection, can be splashed rod "big ends . " This, in turn, can turn the oil into a frothy consistency, such as a well-emulsified salad sauce that prevents it from flowing through your engine to lubricate moving parts. The result is a form of oil shortage and drastic engine wear.
"Too much oil", however, is not an accurate measurement. Note that the dipstick of your engine has a range for a reasonable level, not a single line. Somewhere in this area is perfectly fine, there may be a modest amount above the top level, but I would certainly be nervous a lot beyond that. Each engine design has different dimensions, so it's hardly possible to know what level your engine oil will go French.
If you have significantly more oil than the tip of the dipstick, play it safe and skip something. There's nothing hi-tech about the process: loosen the drain plug as you would with an oil change and leave out a cup or two at a time. Then, tighten the drain plug, start and run the engine for one minute, turn it off, and then recheck the dipstick by wiping it off and then reloading it for proper reading. And do it all while parked on a flat surface, not on ramps.
If you're looking for a fancy way to get oil out of your car, there are vacuum oil pumps for under $ 100. These suck the oil through a long straw from the engine that penetrates the dipstick tube. Personally, I find extractors more work to assemble, clean and empty than the effort they save – and you still have to crawl under the car when you change your oil filter.