What kind of lower unit oil?

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midwestfisher

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Guys/gals, have a new to me 2005 Johnson 115hp 4 stroke and am trying to find out what kind of lower unit oil I should use. (manual doesn't say) In my 2004 Merc 50hp 2 stroke I used 80/90 Quicksilver synthetic oil.
Would any of you know?

Thanks
 
OMC/Bombardier HPF Pro.

This is the only LU gear oil recommended by Evinrude. The special formulation allows for a percentage of water intrusion to be be emulsified into the oil without damaging the internal gears and bearings, and to withstand the 300 hour service interval. Consider that a replacement lower unit costs a big chunk of change! Find it online at Leaders or it can purchased from Barnacle Bills.


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Always best to use mfgr recomendations, they designed the motor, they should know best. I have over the years used a full synthetic 75/140 diff lube that passes all marine specs without any issues. But mfgr specs will always be your safest bet !!
 
Thanks all for the help on gear lube. Now question is crankcase oil. Again it's a 2005 Johnson 115 hp 4 stroke. Manual recommends 10w/30. What would be your recommendations on oil brands? I had a merc 50hp 2 stroke oil injected and used Merc oil exclusively would it matter if I used a Merc 4 stroke synthetic? Sorry for all the questions new to 4 stroke outboards.
 
Thanks all for the help on gear lube. Now question is crankcase oil. Again it's a 2005 Johnson 115 hp 4 stroke. Manual recommends 10w/30. What would be your recommendations on oil brands? I had a merc 50hp 2 stroke oil injected and used Merc oil exclusively would it matter if I used a Merc 4 stroke synthetic? Sorry for all the questions new to 4 stroke outboards.
Honestly, any 10w-30 made for outboards today would be good. Mercury, Yamaha, Suzuki and other outboard manufacturers all have their own branded oils, but Valvoline, Pennzoil, Lucas, and other oil manufacturers also make 4-stroke outboard oils as well. Just make sure you get actual marine outboard oil, not automotive oil. Outboards run at higher RPMs than cars and trucks and the oils made specifically for outboards are formulated to resist thermal breakdown and shearing caused by running longer times at higher RPMs.

Also, you have an 18 year old motor that was run by someone else. Who knows how well they took care of it internally, so I wouldn't stress the small stuff. Personally, I'd just run Merc 90 High Performance Lower Unit Oil because that's what I keep around and is easily available year after year. Johnson/Evinrude products are continually disappearing and who knows how long that lower unit oil will still be available. But to each his own.
 
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Honestly, any 10w-30 made for outboards today would be good. Mercury, Yamaha, Suzuki and other outboard manufacturers all have their own branded oils, but Valvoline, Pennzoil, Lucas, and other oil manufacturers also make 4-stroke outboard oils as well. Just make sure you get actual marine outboard oil, not automotive oil. Outboards run at higher RPMs than cars and trucks and the oils made specifically for outboards are formulated to resist thermal breakdown and shearing caused by running longer times at higher RPMs.

Also, you have an 18 year old motor that was run by someone else. Who knows how well they took care of it internally, so I wouldn't stress the small stuff. Personally, I'd just run Merc 90 High Performance Lower Unit Oil because that's what I keep around and is easily available year after year. Johnson/Evinrude products are continually disappearing and who knows how long that lower unit oil will still be available. But to each his own.

I've always wondered what the different was between the oil I use in my vehicles vs outboard four stroke oil. Now I know!
 
Thanks Striper57, I was wondering if any good quality marine oil would work. I agree that the Johnson stuff is disappearing. So I will use the Merc oil for crankcase. On the gear lube, I have been using Quicksilver 80/90 high performance lube for years. Have some left from my 2 stroke Merc. It's not fully synthetic do you think this would work? I live about 15 minutes from the Merc plant and Merc is the preferred motor around here. Thanks again
 
The Quicksilver Premium 80W-90 is for outboards below 75 hp. The Quicksilver High Performance SAE 90 works in all sizes. I only know that specifically because I just walked by them in Bass Pro. I attached a picture of the two types side by side.
 

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I've found Bass Pro's house brand oil to be the best bang for you buck, both their mix oil and 4 stroke engine oils. $15 a gallon is hard to beat.

My thoughts, 4 stroke outboards will dilute the oil with water or fuel long before they actually break it down. Run the cheap stuff and change it every year.
 
I've found Bass Pro's house brand oil to be the best bang for you buck, both their mix oil and 4 stroke engine oils. $15 a gallon is hard to beat.

My thoughts, 4 stroke outboards will dilute the oil with water or fuel long before they actually break it down. Run the cheap stuff and change it every year.
The Bass Pro stuff is made by Amalie Oil. I've used a bunch of the Bass Pro 2-stroke oil (bought a few cases of it on either Black Friday or the Fishing Classic years ago when it was first released). All that original stuff is gone, but the Bass Pro stuff is still what I have on my shelf for 2-stroke.

4-stroke is a different matter. I have used Mercury, Yamaha, Lucas, and Pennzoil outboard oils, but I have yet to try the Bass Pro stuff. Part of me is a little turned away by the price being too cheap compared to everyone else. I always figure the 2-strokes will eat any TC-W3 at the right mixture, but the 4-stroke stuff has to survive all year in the powerhead. Makes me a little leary. I mean, I feel like my outboard oil should cost as least around as much as the oil that goes in my truck.
 
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Here's a jug of the 2-stroke Bass Pro oil and a quart of Fram Small Engine Oil I just used in my mower. The AOC or the bottom stands for Amalie Oil Company. Also, not to get political or anything, but using AOC as the initialism for your company is really unfortunate nowadays, especially for an oil company!
 

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This old boy is still stuck in two stroke land, havent even entertained the idea of going four stroke. For as far back as I can remember I have used nothing but Pennzoil two stroke oil in all my two stroke engines from weed eater, chainsaw and dozens of outboard motors over many many years. Never had an engine issue, wear out, or other oil related problem. Even use it in my Merc 40 injected system. Previous owner used the same thing as did original owner once warranty passed. Not about to try and fix something that isn't broke !!
 

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