Has someone put dodgy marks on your dipstick m8, you should not be putting 4.5 L in on a change, if you use the manual it will tell you it will take 3L or 3.4L if you doing a filter change too and the initial fill from a new or rebuilt engine is 3.8L, so A 4L can is perfect. I personally agree with cossiep about spending just a bit more to put your mind at ease.