yamaha lower unit oil question

[canadian bassman]

I have winterized lots of engines over the years always used a nataulis lower unit oil with the following specs Extreme pressure formulation Rust protection for longer gear life SAE 90 and it says it Exceeds OEM specifications

The oil I pulled out today ( the dealer did it last yr ) was blue in color am I ok or is the blue just a sae 90 oil with a colorant in it

[headhigh]

I know some of the Merc gear oil is blue, Yamaha may make one also that the dealer used. As long as you're using good quality HP gear oil, it doesn't matter if it's blue or brown.