DF225 Lower Unit Fill Level

[Angler85]

SO i recently purchased a 2021 DF225 and am getting ready to do my 20 hour service. I have never had a Suzuki before so I am a little confused by the three ports on the lower unit for changing the gear oil. Top is the vent port, middle is the oil level port, and the bottom is obviously the drain plug.

Which one of the first two do I fill the oil to? The dealer told me to fill to the oil level plug but the manual says to fill until it comes out of the vent hole at the top. Which one do I fill to?!

[Murray]

Challenge your dealer with the owners manual. Nothing worse than conflicting information.

[Bloggsy]

As per attachment bottom hole is drain and refill top hole is vent to let oil out and in and oil level is to check after 10 mins. as you will always lose a little bit of oil trying to install bottom plug.
This is for a DSF175 so the oil quantity may be different but the procedures are exactly the same.