High Altitude Alpha One & Synthetic Gear Lube

[ridesapaint]

I moved my boat from 500 feet above sea level, to 7800 feet ASL, and when I removed the vent screw on my lower unit I got a face full of gear oil, blue stuff spit and splashed and went everywhere. So I decided to change it out while I was at it. It was full of bubbles, but not milky or water contaminated (I don't think).
The closest marine store is 2 hours, Walmart 1/2 hour, so I put Valvoline synthetic 75-90 GL-5 in the lower unit.
Will the Valvoline synthetic 75-90w GL-5 rated oil cause problems in my Alpha one lower unit? I read a bunch of threads but they seem to be all over the place on this issue.
Tomorrow is supposed to be 70 degrees and no wind, so I am driving up to Navajo Lake in northern New Mexico to take the boat out for the afternoon.

 

[Don S]

Re: High Altitude Alpha One & Synthetic Gear Lube

The GL-5 rating will work OK in your drive, however, the Hi Performance gear lube will actully mix with water, turn milky, and stay in suspenstion should it get into the drive. This keeps actualy gear lube on the bearings and gears at all tiimes.
The standard GL-5 rated synthetic will seperate into water with oil above. Pitty the gears and bearings in straight water. But your Valvoline will work fine till you get the Merc HP.