Re: 88 OMC Cobra drive gear oil?
Make sure to fill from the mid/upper fill hole.
Be sure you get this right! Do it wrong and you'll be replacing the drive! Fill it from the MIDDLE port with the upper one "open". Check it initially with the dipstick resting on the threads "to allow for a slight over-fill".
Biggest difference from auto gear lube and marine is Marine oil resist water.
This is somewhat arguable. Mercury and Amsoil and a maybe couple of others, actually mention that their oil "resists" water contamination and still maintains lubrication qualities.
Other oil manufacturers don't mention it (including "automotive" oil makers)
Since there's really NO (specific NMMA) marine specification for gear lubricant, other than the standard API GL-x rating, there's probably little or no difference in ALL the oils except the differences between synthetic and NON-synthetic oils.
In the future, just do oil changes
at the end of the season, NOT the beginning..........( SEPT or OCT for most of us that park our boats in the Winter)
You want to do this so that if you actually DO develop a leak, you find it before it sits for 6 to 9 months!! (if it's a LOT of water, it could freeze if you experience below freezing temps)
Cheers,
Rick
