On another site an email was sent to Amsoil asking about the suitability of using Amsoil SVG in a marine drive. The reported response from the Amsoil tech was the following:

"SVG is a 75W-90 GL-5 gear lube so it can work in the application. However, we do not recommend it in this application because this application is prone to water contamination. AGM Marine Gear Lube is a much better option as it can function with up to 10% water contamination."

The way I interpret that responce is that the Amsoil SVG does NOT tolerate water contamination. Based on the similar response I got from Redline when I called and asked the same question about their Redline Shockproof Heavy Gear lube I interpret that response to mean the Redline Shockproof Heavy Gear lube does NOT tolerate water contamination.

Buyer beware.

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The Bravo 1 and X1 upper gears are spiral but the Bravo XR upper gears are straight cut gears. The harder/more brittle Bravo 1 and X1 uppers do not need the higher pressure lubes as much as the softer/tougher XR upper gears which are used for the higher HP/torque rating. The lower gears in both are straight cut. Not sure what oil standard Merc recommends when the Bravo drives HP/torque ratings are not exceeded but most gear issues with these drives (and the reason for my interest) are related directly or indrectly to when the HP/torque ratings of these drives are exceeded. In those cases the highest performance EP lube is obviously desired....ie GL-5.