Marine gear oil vs. auto gear oil

Evinrude Boater

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Is there a difference between your run of the mill SAE 90 weight gear oil and the pricier marine gear oil? My car mechanic says they're the same except for the price. I'm running it in a 1964 Evinrude 75 hp. Should I get him to fill my bottle from his bulk barrel for a buck?

Also, what is Type C gear oil? I have a bottle of Shell Nautilus SAE 90 and a bottle of store brand Type C that says it SAE 75. Can I mix them?
 

Solittle

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Re: Marine gear oil vs. auto gear oil

Gear oil is definately not the place to try to save money. Marine grade oils have additives that will allow some water to emulsify (mix pretty well) thus giving some protection to the highly machined inner workings of the grar case.
 

jbjennings

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Re: Marine gear oil vs. auto gear oil

OOPS!
Better change mine out, too. Interesting.
JBJ
 

_brad_

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Re: Marine gear oil vs. auto gear oil

I respect anyone wanting to buy marine gear oil and nothing but marine gear oil, however, I beg to differ.

I have always used name brand automotive gear oil in my 1977 70 HP Evinrude without any issue.

Yeah, marine gear oil may mix better with water, but, why in heavens is there water in your gear case to begin with?! :D
 

Laddies

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Re: Marine gear oil vs. auto gear oil

Brad, you don't seem to under stand that his unit is a electric shift and yours is not, even standard standard marine gear lubee will ruin his unit thats why they spent the time and money to devolpe type C lube. You are right that any GL-5 rated oil is suppose to work in most units and does work in some but I wonder why you would give that advise on something that you apparently don't understand, if you choose to make the $800 mistake on your engine it's one thing why talk someone else into it to save 5 bucls
 

mrfixitman40

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Re: Marine gear oil vs. auto gear oil

Is your rude an electric shift or a mechanical shift they made both from what i have seen and my manual shows both. if it is electric it needs type c now called premium blend from evinrude
 

Scaaty

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Re: Marine gear oil vs. auto gear oil

If its a electric shift, the 90wt will kill it quick...needs the lighter type C..period, end of story
That said, seems Walmart have LU oil 'bout the same price as car stuff, which belongs in a car. But you will need a dealer for the Type C.
Marine oil is lower foaming, and better mixes with water to hold it in suspension. And yep, water gets in there sooner or later..
 

jimmbo

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Re: Marine gear oil vs. auto gear oil

my $.02

In the late 70s and early 80s my uncle was having repeated upper gearcase failures on his OMC sterndrive. This unit was a later model that was a hydro-mechanical shift so it didn't need Type C and was speced for Hi-Vis. He would have it rebuilt and it would be fine for the rest of the season, about 4 months up here. His "expert" friend would winterize it for him, changing the lube, fogging etc.
About 2 or 3 weekends into the next season the upper gears would fail again. This happened 3 years in a row so there was a pattern. One day after hearing my uncle complain about the drive I asked what oil was in it. He said he didn't know but it was what his bud put in it. I questioned his friend and he said "140w rear end oil". I asked why he didn't use OMC Hi-Vis as it was speced. He stated there was no difference except the price and what did I know since I was only a teenager.
I suggested to my uncle that the next time he winterized the boat that the proper oil be used. After that happened he never again had a gear failure.

I had been told, and it was about 30 yrs ago, that the Marine gear oils had more EP additives to help the small gears survive the high loads placed on them.
 

Evinrude Boater

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Re: Marine gear oil vs. auto gear oil

My 1964 Evinrude 75hp is in fact a mechanical shift model. I don't know why I bought the Type C oil. I guess I don't need it and can let the kids put it on their bicycle chains.
Interesting discussion though. I'm going to bring it up with my auto mechanic again and ask him a few pointed questions.
A little bit off topic, I was talking to Bill Mayer (Mayer's Marina, New York) about mix ratios for fuel and he seems convinced that 50:1 is too little oil for these motors and recommends something between 50 and 24:1. I forget what ratio exactly but more is better...to a certain extent. I suppose he's been around long enough to see the difference in engine longevity. I for one want to pay a bit more for oil than find pistons and rings.
 

jimmbo

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Re: Marine gear oil vs. auto gear oil

1964 was the year that Evinrude and Johnson switched to 50:1 and the oils weren't as good then. Use a GOOD TC-W3 oil @ 50:1 and relax

Back in 64 Type C was used in all the Johnrude gearcases. Probably cause it was the only gear oil they marketed.
 

Evinrude Boater

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Re: Marine gear oil vs. auto gear oil

Mixing any lower than 50:1 is like skiing behind a motocross bike. Cough, cough....
Speaking of "Good" oil, what constitutes "good" TC-W3? I use our local auto store brand marine oil at $16/gal vs the Shell Nautilus at $24/gal. Is it marketing or is it 50% better?
 

jimmbo

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Re: Marine gear oil vs. auto gear oil

This is a never ending topic.(Manufacturers oil vs. Wally world oil) There are several posts regarding oils. I feel you can't go wrong with the engine makers brands. I always bought Merc or OMC oils. Others feel different. As for the extra cost... $10 or $15 more per gal is usually less than $50 per year for most boaters. You paid a small fortune for the engine... so why cheap out on the oil
 

dingbat

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Re: Marine gear oil vs. auto gear oil

Mixing any lower than 50:1 is like skiing behind a motocross bike. Cough, cough....
Speaking of "Good" oil, what constitutes "good" TC-W3? I use our local auto store brand marine oil at $16/gal vs the Shell Nautilus at $24/gal. Is it marketing or is it 50% better?

It sounds like you need to find a new oil supplier. I can get Pennzoil Premium plus for $12 a gallon at Wal-Mart. Mercury Premium Plus for $16 a gallon at BPS on sale and full synthetic for $22 a gallon just about anywhere.

The replacement cost for my motor is almost $15K so I take the middle ground and run the Merc oil in it.
 

OhWellcraft

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Re: Marine gear oil vs. auto gear oil

I have heard from many that the automotive grade can foam a lot more than the marine. since auto rear ends have a vent on them this isn't a problem. But on a LU there is no way to vent it the same thus the possibility of pressure buildup from the foaming. Also they don't make a type C in auto. For the extra few bucks it costs for marine grade I would never make my outboard a guinea pig to find out.....
 

BillP

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Re: Marine gear oil vs. auto gear oil

Standard auto gear oil in a mid 60s 75hp OMC? Never had a problem with it in my 1965 75hp Johnson (with electric shift even). Years and hundreds of hrs on a motor that already had 20 yrs worth of use. Zero foaming, zero shifting issues, zero metal slivers in the oil, just plain zero problems...even when the seals leaked and massive amounts of water got into the gearcase. I sold it to a friend who used it another 2-3 yrs and he sold it still in perfect running condition.

Auto oil specs were and still are the same that ob mfgs spec in their handbooks. Whether marine gear oil actually makes a difference is more hype in my book than fact. There are only glossy ads and hearsay to say different. However, I use marine grade in my modern motors. Why not? It's a few $ more and I don't have to deal with mystery. I would not hesitate to use auto oil if I got into a jamb though.

bp
 

Scaaty

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Re: Marine gear oil vs. auto gear oil

Standard auto gear oil in a mid 60s 75hp OMC? Never had a problem with it in my 1965 75hp Johnson (with electric shift even). Years and hundreds of hrs on a motor that already had 20 yrs worth of use. Zero foaming, zero shifting issues, zero metal slivers in the oil, just plain zero problems
bp
OK, try it in a LOT colder water than Florida 80 degree ...the heavy cold stuff will kill a Selectric shift..
 

BillP

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Re: Marine gear oil vs. auto gear oil

OK, try it in a LOT colder water than Florida 80 degree ...the heavy cold stuff will kill a Selectric shift..

Another 1965 omc with elec shift is NOT in my future and moving to cold water isn't either. My experience with that motor is merely empiracle data that shows a few hundred hrs of use without a problem. Use it however.

Anyway, Type C is 80w (syn is 75w) and was speced (not auto ATF) for that elec shift. Oil mfgs now advertise 80-90 high vis can be used where C is specified. Whatever though, a 1964 mechanical shift can use auto gear oil that meets 1960s gear oil specs without a problem. In the 50s/60s they also speced (in the book) to use regular 30w car oil in the gear case for temporary use.

L8R.
 
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