I have just done an oil change on my 2010MY XKR and managed to suck about 6.5l out. I then have only be able to put 6.25l back and the digital oil meter is showing Level OK (and full).

Apart from the obvious did I get all of the oil out? (I am sure I did as I was using a compressor based vacuum extractor and double checked it) if there another explanation that people have experienced e.g. faulty sensor, sensor always reading low?

Many thanks in anticipation.

 

I do it the opposite, drain the sump, replace the filter and then add the correct amount of oil. Run it for a minute or two and let it sit for a while and then see how much is on the stick. That's the real 'full' mark. In past cars I've checked it a quart low and even two quarts low for reference.

 

Ranch , no stick on the 5.0L engines. It's electronic.

 

Your procedure is correct . After you put in the oil I assume you start the engine and let it idle until it gets to normal operating temp. Shut it down and wait 3-5 minutes and then do the oil check. Top off if necessary and drive it. Recheck it the next day. Remember the oil filter goes in dry so that fills on initial start up. There will always be a small amount of oil in the system that won't come out. I don't know is 1/4 L is to much but a second and 3rd check will sort it out.

 

The electronic gauge should be accurate to within a quart. If not I can understand how some have run out of oil.