After doing a few seals and stuff I filled up the oil to just a little below the full hole on the dipstick. About a month later, today, I checked my oil out of interest once the car had warmed up to find it a bit over the full mark. Is it normal for oil to expand when its heated? And is the full mark for cold oil?

The mark is for cold level, and like everythig else, oil does expand somewhat on heating. For a noticable change however, you may be looking at water and petrol dissolved in the oil, which is quite normal. does the car get a lot of stop start driving?

The mark is for cold level, and like everythig else, oil does expand somewhat on heating. For a noticable change however, you may be looking at water and petrol dissolved in the oil, which is quite normal. does the car get a lot of stop start driving?

 

yeh in brisbane, no doubt.

now i have fixed all the leaks i might just run it a bit lower so the oil level is never over bottom of the crank gear for the cam.

Not sure about Subies but most cars I've dealt with the oil is to be checked hot (engine off). And yes oil can expand significantly from cold to hot, I havent check it on my Subes but I've seen differances of 1/4 or more on the stick for some cars from hot to cold.

 

Gary

Not only does the oil expand, but it also gets a certain amount of entrained air mixed into it. The tiny air bubbles will float out, but it will take several minutes.

The verdict, running with over full mark while the oil is hot, does this do damage?

Your oil would have to be very overfilled to cause damage. Just a little won't do any major harm.