ATF in mechanical gear box?

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ancora

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At a dockside gabfest, someone suggested I use ATF in my Volvo mechanical, non-hydraulic, Volvo gearboxes. Any thoughts on that?
 
What does the book say to use? Stick with that guidance. Gear reducers use a variety of non ATF oils with some up to 90wt or higher. Gear lube and hydraulic oil are two very different products.
 
I had a Yanmar w a Kansaki gear (mechanical) that spec'ed ATF.
Was a very noisy gear box.

Tom and Marin offer the best advice here but I ran a mixture of several things in addition to synthetic ATF to maximize the viscosity of the oil so as to quiet down the Kansaki gear box. All my additives didn't quite cut it noise wise so I installed an electric bronze gear pump and a cooler. That did it.
 
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Pay attention to Sunchaser. Use what the manual says to use. If you don't have a manual find one. Often they are available on the internet or someone on forums like this one can make you a copy of theirs.

Engines and transmissions are not something you want to make decisions on based on anything you hear in a "dockside gabfest," either on a dock on on a computer.
 
At a dockside gabfest, someone suggested I use ATF in my Volvo mechanical, non-hydraulic, Volvo gearboxes. Any thoughts on that?
I would use what the manual recommends and nothing else except in an emergency and in thet case, I would drain it and replace it with the proper lubricant ASAP.

My Volvo gearbox (they call it a "reverse gear") takes engine oil, Yours may be different.
 
At a dockside gabfest, someone suggested I use ATF in my Volvo mechanical, non-hydraulic, Volvo gearboxes. Any thoughts on that?

Some gear boxes like my Borg-Warner recommend either... with regular oil being preferred if staying below 3000 rpm.

So ....many people with "opinions" can be partially correct..or partially wrong. The faster reving gear boxes probably need something antifoaming...thus tranny fluid.

The gearbox manual wins out with the exception if it's antiquated for oil specs...some newer varients with better properties would be fine as long as they are meeting the spirit of the oil requirement. In that case a call to the manufacturer/warranty shop may trump the manual.
 
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Changing the Mfg spec is never a great idea , but changes in specs DO change over the decades.

Get todays !

For a gear box Synthetic may run cooler and lube better.

FF
 
FF's response is precisely the issue, no details as to viscosity, weight, type - just use "synthetic." You cannot go wrong by going by the book. The notion that gear engineers of 20 or 30 years ago were in the dark ages on this subject is just plain silly. For reference look up Cat, SAE Chevron, Shell and ASTM lubrication test procedures and note the dates for setting of standards and lab equipment used.
 
FF's response is precisely the issue, no details as to viscosity, weight, type - just use "synthetic." You cannot go wrong by going by the book. The notion that gear engineers of 20 or 30 years ago were in the dark ages on this subject is just plain silly. For reference look up Cat, SAE Chevron, Shell and ASTM lubrication test procedures and note the dates for setting of standards and lab equipment used.

No one is saying old time engineers were in the dark ages... but there have been advances in lubrication and to not recognise that is just as much in the dark ages...such that later editions of owners manuals for THE EXACT SAME ENGINE now specify multi-viscosities, higher standard oils, synthetics, etc...etc...:rolleyes::rolleyes::rolleyes:

My great grandmothers sewing machine specified sperm whale oil..get me some please....:D
 
Changing the Mfg spec is never a great idea , but changes in specs DO change over the decades.

Get todays !

For a gear box Synthetic may run cooler and lube better.

FF

That (discussion with FF) is one of the reasons I went to synthetic in my BW velvet drive. I know from my bearing experience that tranny fluid is not the greatest lubricant and synthetic is much better, and I know that heat is a big factor in marine trannys. So after a long discussion with the technical folks at my local BW distributor I made the change to synthetic 5-30 when I did the rebuild.
This was not based on a discussion at the dock or with a marine gearhead/mechanic.
 
Synthetics and their advantages in some cases are not new, they are entering their 7th or so decade of use. As for the engine going from straight to multi weight, that is not an advancement in lubricants, that is better thinking on the part of the engine manufacturer.

By the way Jay, how hot does your transmission run? My Hurth ZFs seldom get above 115 degrees.

I'm still waiting for Ancora to say what the book recommends for his tranny, then our shade tree opinions and dock talk can get narrowed down.
 
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"but there have been advances in lubrication and to not recognise that is just as much in the dark ages.."

The basic "advance" in dino oil has been in the area of the oils detergent ability, that's it.

Gov mandates removing lubrication from fuel and the far more distructive practice of forcing the engine to operate on its exhaust ( EGR) has forced the oil mfg to need better detergent and operate at far higher temperatures.

60 years , of chemistry ,for mandates , not better lubrication.

FF
 
By the way Jay, how hot does your transmission run? My Hurth ZFs seldom get above 115 degrees.

I use a temp gun on the hyd fittings on the each side of the gear cooler and usually get 105/110 F going in and 100/105 F comming out. That's "loafing it" at 1600/1700 rpm on the Lehman 120.
 
When we had a issue while traveling where the reduction gear (Velvet) cooler sprung a leak and resulted in the reduction gear oil being sucked out via the cooling system we were stuck as we didn't have any ATF which was the oil used. We dumped in 40 weight engine oil, crossed our fingers and completed the voyage without any furter issues. ( We used marine tex to close the holes in the copper cooler which was rotten)
Our diesel Doc said not to sweat it. ATF was used in part, to allow for the color (dye) in ATF to indicate a leak. This mechanic recommended and uses engine oil in all of the reduction gears. We continued doing so with that boat and now with our replacement boat, we do as well.
Regards
A.M.Johnson-Ketchikan (Bridge to Nowhere)-Alaska
 
ATF is very good at penetration and is a very high detergent .

Its frequently used to clean out an old gunker with noisy hyd tappets.

Dump in a quart or two drive 100 miles drain and the lifter noise should be gone.

One advantage to synthetics is their sheer strength which is of use with gear teeth that mesh.
 
The (manual) transmission on my '97 BMW M3 calls for ATF too, in addition to stating so in the manuals there is a big orange sticker on the side of the transmission saying "ATF Only". I suspect it gets a much harder workout than a boat tranny.
 
FF re post # 15. With modern oils I have not seen a dirty internal engine in 12 / 15 years, atf flushing went out 30 years ago.ATF is not for internal combustion engine use or as a top end lubrication, will do more harm than good.
 
Quaker State Oil Companies recommendation:

Myth_ATF.png


Motor oil and ATF are the same oil.

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Motor oils and ATFs are formulated differently. Motor oil is formulated to withstand the harsh combustion environment of an engine and reduce friction, while ATF is formulated to provide specific frictional properties for a transmission.

Myth_ATFOilChange.png


Adding a quart of ATF to your engine the day before an oil change will clean the engine due to the high levels of detergent in ATF.

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ATF is not formulated to withstand the combustion environment inside the engine. Quaker State® recommends that you keep the fluids where they belong: motor oil in the crankcase; automatic transmission fluid in the transmission.

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Adding oil additives means you can extend drain intervals and engine life.

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Engine oil technology has rapidly advanced in the past decade, making today's high-quality engine oils second to none. Now, vehicle owners have a choice between conventional, synthetic blends and full-synthetic engine oils positioned to provide the best protection for their application and driving needs. However, there are consumers who want to provide value-added protection to their engines through the use of engine treatments. Although there are several engine oil supplements on the market today, consumers must remember that the Original Equipment Manufacturers (OEMs) have stated in the vehicle owner's manuals (i.e., 1999 Chevrolet Silverado page 6–15), "Don't add anything to your oil. Your dealer is ready to advise if you think something should be added."


Motor Oil, Transmission Fluids & Synthetic Oil | Quaker State

Mobil Oil's web site say about the same thing. :hide:
 
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