Gear Oil Which one?

smithrock

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As far as gear oil goes for the outdrive, does it really matter which brand is used? ie: Mercury, Lucas, Royal Purple, Mobil etc.........
 

Gary H NC

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Re: Gear Oil Which one?

Myself i would use the Merc premium gear lube..Its the good stuff.
Everyone has different opinions on oil...As long as it is GL-5 rated gear lube it will work.
 

smithrock

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Re: Gear Oil Which one?

Myself i would use the Merc premium gear lube..Its the good stuff.
Everyone has different opinions on oil...As long as it is GL-5 rated gear lube it will work.

What about synthetics?
 

Rocky_Road

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Re: Gear Oil Which one?

I agree that the Mercury High Performance is the best on the market...but, the OP never stated what outdrive he is working with.

If he is running any of the Mercruiser outdrives..then he can't go wrong with the Mercury lube. I can't make any recommendations for the other outdrives out there....
 

Don S

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Re: Gear Oil Which one?

Merc Hi Performance is the good stuff (it's green to blue green in color). There is also a Merc PREMIUM gear lube (looks the same color as oil).
They are NOT the same.
New Merc outdrives and most lower units on outboards are filled with PREMIUM gear lube for breakin. After that, the recommended it Hi Performance gear lube.
I have no problems using the Hi Performance gear lube in my Volvo DP (When I had it) and have no problem recommending it for use with Merc, OMC Cobra drives, Volvo DP and all SX/DP-S drives. (Not Volvo single prop drives 93 and earlier.)
 

smithrock

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Re: Gear Oil Which one?

Merc Hi Performance is the good stuff (it's green to blue green in color). There is also a Merc PREMIUM gear lube (looks the same color as oil).
They are NOT the same.
New Merc outdrives and most lower units on outboards are filled with PREMIUM gear lube for breakin. After that, the recommended it Hi Performance gear lube.
I have no problems using the Hi Performance gear lube in my Volvo DP (When I had it) and have no problem recommending it for use with Merc, OMC Cobra drives, Volvo DP and all SX/DP-S drives. (Not Volvo single prop drives 93 and earlier.)

I was reading about mercury gear lube and you are defintely right, thay are not the same! in fact, the two CAN'T be mixed!
 

four winns 214

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Re: Gear Oil Which one?

OK, I know that Merc Hi Performance and Premium are different and can't be mixed. My question, if you're draining one and refilling with the other is there any flushing of the old (besides draining it) that needs to take place?
 

Don S

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Re: Gear Oil Which one?

OK, I know that Merc Hi Performance and Premium are different and can't be mixed. My question, if you're draining one and refilling with the other is there any flushing of the old (besides draining it) that needs to take place?


Nope, just let it drain for a while.
 

83Evinrude

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OJ_Simpson

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Re: Gear Oil Which one?

And what if you were to mix High Performance and Premium Gear Lube Oil? Also, where can you get the washer that goes with the drain screw that fits into the lower unit? Oops, mine happened to fall into the old gear lube and was hoping to just pick one up (cheap) at west marine or bass if they readily carried them.
 

Rocky_Road

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Re: Gear Oil Which one?

And what if you were to mix High Performance and Premium Gear Lube Oil? Also, where can you get the washer that goes with the drain screw that fits into the lower unit? Oops, mine happened to fall into the old gear lube and was hoping to just pick one up (cheap) at west marine or bass if they readily carried them.

I got a blister pack of the Mercruiser gaskets at my local West Marine...but not every West Marine carry the same items, so call ahead!

Happy boating!
 

myoldboat2

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Re: Gear Oil Which one?

I believe marine gear lubes can have additive packages that are designed for the marine environment, e.g. will hold more water in suspension if there is intrusion into the gear case. Merc even claims it... "Specifically formulated to help prevent failures due to water entering the gear housing."
 
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