Lower Unit Lube Choices

[New Yankee]

Hey guys,

With the temps rising I'm going to do some spring maintainence on the Merc. Got to wondering if their is real value in buying QuickSilver/OMC or other "marine" formula gear lube (I know it should have been done this Fall - learned that here I think). Seems that a quality 85W-95W gear oil that meets API GL-5 rating would be the same(?).

It's not that the couple bucks is any big deal, but the idea of paying for advertising/labeling and nothing else kinda stinks.

After researching a pretty good bit on 2 stroke oil, I came to the conclusion and fact that Walmart's Super Tech (TCW-3 and NMMA certified - made by Shell) is at least as good as most other and better than quite a few 'name brands'(blends and synthetics not necessarily included) and at six bucks a gallon as compared to twenty, well you see my point.

Any thoughts?

[Enids Hubby]

2 years ago I was servicing the lower unit on my Merc with an off brand lube , Can't remember the name but I think it was in a white and blue tube. I have the clear hose that screws into the tube and into the lower unit so you can see it go in . As I was squeezing it in you could see specs or small bits of black stuff going in with the nice clean looking fluid. I've never seen that with any other type of lubricant. I drained it out and went to the marina and bought the Merc brand . Spend the extra 2 dollars just for piece of mind.

[New Yankee]

With a little left clickin' I found the answer to my question - the marine blends are designed to emulsify any water that might enter the gear case, the auto/machinery blends do not. Not a big deal if you're CERTAIN you have no water, but if not, any that enters will settle at the bottom where you need the lube the most.

Makes sense to me, I'll continue buying the mairne blends.

FYI - a lot of tech info on boats and lots of other stuff at "iboats dot com" no need to spell the dot.

Thought someone else may want the answer.

[Surface Tension]

Use a gear oil for outboards ONLY.
Auto gear oils will be whipped to a froth in your lower unit.

IP: Logged

[oilguy]

Mobil 1 Synthetic works for me. Changed out the oil in new 115 yam four stroke as soon as I got it. Never even gave it a second thought!

[musky hunter]

Nothing wrong with the Mercury product. But I run Amsoil gear lube because of the previously mention water emulsificaiton. My gear case needs a little work, even though I replaced an output seal last year it still takes on a little water. The Amsoil still works good, even when wet. It's interesting, when emulsified oil is drained out it's kind of green in color. Eventually the water will settle out of the oil, and it again reverts to the clear yellowish state. I have filterd and recycled the dewatered stuff with no apparent problems.