Gear lube(lower unit) quality/interchangeability ??

[jddenham]

I was just at the dealer inquiring about gear lube for three motors I have. 1959 Johnson 50HP V4, 1973 Johnson 115HP V-4, and 1975 Mercury 1500 L6. He said I could use the same lube in all three units. He also said that I could use any 80W-90 gear oil(lube?).

Is this true? Non of the units are electric shift.

Is there a marine spec similar to 2-stroke oil?

Would it be better to use a universal type gear oil from walmart and change it often, or use a manufacturers and change it per regular intervals?

What would be a good oil I can use in all three engines, or is there one?

 

[HighTrim]

Re: Gear lube(lower unit) quality/interchangeability ??

Some of the synthetics are better, especially if you take on any water at all. As long as there is no leaking, I think every fall is a good time to change the oil. Just be sure to change the drain and vent gaskets with every lube change.

 

[F_R]

Re: Gear lube(lower unit) quality/interchangeability ??

The major OEM oils are probably better than the Wal-mart cheapo which is probably just plain ol' gear oil if the truth were known. But either one will do. The higher horsepower motors put some pretty significant loading on the gears, which is why I would expect their oil to be superior. Wal-Mart is plenty good for that old fat fifty barge boat beater.