JP wrote:
Hello All,
I have 2001 4.3 Liter Mrecruiser I/O. I know all the Merc manuals all
say use only the Merc brand oil, but I want to know if using Mobil 1
synthetic will be better for the engine (since it is in a Blazer or S-10!!)
I know Merc wants to sell oil, but are there any cons to using synthetic
instead of the Merc dinosaur juice? Thank you in advance.

Jerry



It won't be worse or detrimental. It will cost more... but not much in
the big scheme of boat ownership.

It could provide better protection in severe service or extended storage.

5W-30 would be adequate, 15W-40 too. I've used both in our antique inboard.

Rob