Mid 50’s gear lube

[drifter]

I have collected and worked on countless OMC outboards from the mid 50’s. Never thought too much about lower unit gear oil as I run my motors infrequently and check for water intrusion annually.
I’ve always used Walmart’s standard 80/90 gear lube (not specifically for marine use).
Recently, I read an article about the use of GL-5 rated oils in lower units of older outboards. Article stated that it was a definite no-no as the bronze bushings will be attacked by the additives in the GL-5 oils.
So what is the recommendation for the mid to late 50’s OMC lower unit lube? Must it state “Hypoid”? Walmart’s Super Tech Marine gear lube 80/90 doesn’t state Hypoid. It does state GL-5.
What about Quicksilver brands.
Thanks for your recommendations.

[fleetwin]

Hmm, don’t really know…Would love to read this article though…Wonder if the OEM stuff is: GL-5 rated… If so, I would tend not to worry about the claims that the GL-5 lubes will damage the bronze bushings….

[frankr]

I’ve read that stuff about attacking bronze bearings. Personally, I think it is a bunch of horse hockey. Just my opinion. Oils haven’t been marked Hypoid for years.

[The Boat House]

• This reply was modified 3 years, 9 months ago by The Boat House.

[bobw]

I did some research on this subject some time ago. A google search on the topic of “yellow metal safe” will reveal a variety of opinions, theories and alleged discussions with various oil company technicians on the subject. Most of these discussions opine that a GL-4 rated oil is probably a safer bet to use to protect bronze or brass components. CRC Sta-Lube still offers a GL-4 rated oil and it does specifically state that it is not corrosive to bronze, brass or copper components.

https://www.crcindustries.com/products/api-gl-4-multi-purpose-gear-oil-85w90-32-fl-oz-SL24229.html

Many other discussions indicate that the sulfur additives initially used in some GL-5 oils were found to be harmful to brass and bronze, manufacturers changed their composition to inactive sulfur to avoid such damage. But what do I know, I’m no chemist. I’m with Tubs, I’ll just run them.

Bob

1937 Champion D2C Deluxe Lite Twin
1954 Johnson CD-11
1957 Evinrude Fastwin 18
1958 Johnson QD-19
1958 Johnson FD-12
1959 Johnson QD-20

“Every 20 minute job is only a broken bolt away from a 3-day project.”
"Every time you remove a broken or seized bolt an angel gets his wings."

[bobw]

Drifter – I did a little more looking around this evening and find that the Quicksilver brand gear lubes are rated GL-4 so would contain a lower content of the sulfur additive which has been blamed for damage to brass or bronze. The Quicksilver Premium Gear Lube is specifically recommended for all outboards below 75hp (except for OMC electric shift units), so that might be a good choice.

Bob

1937 Champion D2C Deluxe Lite Twin
1954 Johnson CD-11
1957 Evinrude Fastwin 18
1958 Johnson QD-19
1958 Johnson FD-12
1959 Johnson QD-20

“Every 20 minute job is only a broken bolt away from a 3-day project.”
"Every time you remove a broken or seized bolt an angel gets his wings."

[ShortyLaVen]

I don’t have a lot of experience with outboards, but this topic has been around in the classic car world since GL-5 came out. I have always heard about the concern over bronze bushings/bearing, but I know of a lot of people who have been running it in their vintage transmissions for years and the brass synchros don’t seem to be effected much, if at all. Personally I’ve been running it in the Muncie M-21 four-speed in my old Chevy for at least two years, and in the old three-speed for years before that.

I feel like regular wear from use will kill any brass or bronze parts before anything in the oil will. Those yellow metal bushings are likely considered wear-items anyways, right?

[labrador-guy]

I buy 80/90 at wallieworld by the gallon. The label clearly states it is not harmful to copper or brass bushings. That is good enough for me.

dale

[The Boat House]

• This reply was modified 3 years, 2 months ago by The Boat House.

[outbdnut2]

I use a lot of gear oil, so I now buy it in a 5 gallon bucket, and one purchase lasts me a few years – it’s GL-5 rated:

Dave

https://www.iboats.com/shop/sierra-18-9600-5-premium-gear-lube-5-gallons.html

or cheaper here at Amazon (not sure why the graphic came up instead of the typed amazon address:):

https://www.amazon.com/Sierra-18-9600-5-Premium-Lower-Unit/dp/B00021UR28/ref=sr_1_1?dchild=1&keywords=Sierra+18-9600-5&qid=1594504086&sr=8-1

$109 at Amazon with free shipping isn’t bad for 5 gallons!

[/url]

• This reply was modified 3 years, 9 months ago by outbdnut2.
• This reply was modified 3 years, 9 months ago by outbdnut2.
• This reply was modified 3 years, 9 months ago by outbdnut2.

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