Changed the oil and filter in my new to me 07 ltz400. I drained the tank and the crankcase. The book says. 2.1qts.sticker on the quad saya 2000ml. I put 2 qts in it which would be 1912ml. I assumed this would get it on the stick atleast but it didn't. I kept adding and checking and it took almost 3 qts. An internet search only turned up threads about oil gushing out if overfilled. Thoughts?