2000 nissan xterra 3.3L, I put too much engine oil in it.

Just drain the extra oil out first. It may clear up.

If you have been driving it around a lot with 3 extra quarts then the oil can foam up and does not drain back down and this can wear out he seals, piston, rods ect and causes heat damage because it insulates and can cause piston slap and knocking. I have heard many say if its made it to this point it is trashed. But on an optimistic point I have heard of others who have drained all oil and soaked the engine with diesel fuel and turn the motor over with coils unhooked to keep it from starting either a few times with the starter or by hand with a wrench to get the foamed up oil off the internals and repeat a 3-5 times and drain it and repeat as needed at least 3 more times just rinse it out as it can take a little bit of time to break down the oil if its started to cook to the internals and works in some cases and works easier on those that are foamed but not dried/cooked yet.

To add more information to the above answer I gave. If it has been ran until oil has foamed pull a valve cover and look into the oil drain passage ways to see if they are coated or clogged with the foamed oil if so you have a lot of work ahead of you, along with the above procedure you also need to pull each valve cover and then the heads & intake manifold and use a oil passage way cleaning tool to clean out those passage ways and push it threw the block passage ways and pull oil pan off and make sure to get out all the cooked/dried oil from passage ways out and rinse and clean off all the lower end parts, and clean oil pan and oil pump screen and if its stopped up replace it and put it all back together and do another diesel fuel rinse and change oil after a few weeks or with in 500 miles afterwards.

My ac leakes on the passenger side what do I do 2000 Nissan xterra xe / xterr