Transmission Non-Detergent Oil

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Pgitug

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Nordic Tug 37 2002
Talked with support at Twin Disk today regarding several questions I had and found out that they recommend using Non-Detergent 30 or 40 oil. Regular, off the shelf oil has detergent, which wears out the friction plates quicker than Non-Detergent Oil. Anybody else heard about this?
 
Non-detergent 30w is pretty easy to find. I'd use whatever the factory recommends.

Ken
 
Is ATF non detergent?


Case in point is when oil is used in a tranny. Different than ATF. But to answer your question.......I don't know.
 
In the "good ole days" Caterpillar dozers and most other Cat equipment ran a 30 weight oil in the engine, hydraulics, trans, bevel gear cases and I believe the final drives as well. Simple. Hard for the lube guy to screw it up.


1983 Present 42 Sundeck
Twin Lehman 135's
✌️
 
I have a T.D. 506 and T.D., in the[my] book says, 30 wgt engine oil. No mention of non detergent oil at all. Actually there is a little table depending upon typical seawater temps to use from 20 - 40 wgt.

I think I'd call back and try talk to someone else about that specific question. If that is the case then there are literally thousands of us who have been using the wrong oil for many years.
 
Detergents are polar substances that bond with combustion byproducts and also provide a reserve alkalinity to neutralize the acids formed during combustion.

As a marine gear doesn't produce any combustion byproducts, it probably doesn't require detergents. Detergents may foam in some gearboxes and entrain air between the gears (or friction plates?), decreasing the boundary lubrication.

Foaming is a function of speed and temperature (and probably vapour pressure and viscosity, but don't really know or remember), so it may or may not be an issue in your gear. Observe the bullseye under various load conditions.

If the manufacturer recommends it, it may be a good idea to run non-detergent; and if that is the case, why wouldn't you?

IIRC, the AGMA, had switching to non-detergent oil as a recommendation for foaming troubleshooting. I can look that up in the morning when I have access to my reference material.

Edit: Foaming itself may not have to much to do with the detergents in no detergent oil, but more with the quality of the base oil used. Some foaming is normal in gearboxes, often you can see bubbles collapsing on the surface. It is the micro bubbles that lighten the color of the oil itself with entrained air that is harmful.

By the way, thus information is just (very) basic tribology information gleaned from my life in heavy industry. It may or may not be relevant to your specific application. However, it may support why Twin Disc recommended non-detergent oil.

Edit (again): I just looked at a few exploded diagrams of Twin Discs, and it may not have anything to do with foaming at all, but perhaps the amount of fine splines, and the tendency for detergents to bond to metal parts, possibly "gumming up" the internals and not allowing, or slowing the engagements of the clutch, leading to more wear. I'm intrigued. Maybe I'll call them myself, as I can't find anything in their published manuals recommending non-detergent oil, but much anecdotal information about TwinDisc engineers recommending non detergent oil.

Either that or RickB will come along, slap my peepee, and provide the correct information in the morning...
 
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Outboard oil is non detergent , 30 wt is common.

My TD wants 50wt , at many motorcycle dealers.
 
TD publishes a list of approved oils, it's probably on their site. Plenty of detergent oils on the list.
 
The most popular non detergent is chevron delo 100. It's hard to find but most marine stores carry. Been using delo 100 for 20 years. DELO means Diesel engine lube oil.
 
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DELO = Diesel engine lube oil.

I like that one.
 
Case in point is when oil is used in a tranny. Different than ATF. But to answer your question.......I don't know.

ATF is highly detergent. (old schoolers used to add a qt. of it to the engine before changing oil to clean them out).

I think some words might have gotten mixed up.

I believe the issue is putting oil in that has friction modifiers, and oil that doesnt have that is getting harder and harder to find.
 
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During my time with the Cat dealership- Rotella 15w40 was the only oil that EVER got put in.
Mostly- it seemed to be what the OTR truckers wanted. 3406 B models ruled at that time. ;)


1983 Present 42 Sundeck
Twin Lehman 135's
✌️
 
I'll take a wild guess that ATF is used because it has dye which would identify the source of oil in the bilge. Velvet Drive called for ATF as I recall, however all the marine mechanics I deal with are comfortable with using non-detergent 40 or even 50 weight oil, brand is not a consideration.

Al-Ketchikan
 
In "modern" oils 15 or 20% of the oil is an additive package,

With no need for thickening agents , anti foam agents etc, perhaps there is simply more oil in the non detergent oil?
 
FF yes I agree .... there's more oil in the oil. That's one of the reasons I use non multi viscosity lube oil in my boat engine.


Lube oil for transmissions need additives too. Anti foaming agents for one. They probably don't need additives for water absorbstion but corrosion control agents wouldn't hurt. Anti wear agents too. And as far as I know all gasoline engine lube oil has additives that reduce the ability for gasoline to mix w oil so it will stay on the surface and not mix. Two stroke oil obviously dosn't have that. And there's probably much more that dosn't occur to me.

ATF is recomended for my BW VD and I use it. It's probably only intended for automatic transmissions. I had a stick shift car that spec'ed 10W30 engine lube oil. There probably isn't a lightweight oil for straight stick shift automotive type gearboxes or mechanical small boat transmissions that is specifically formulated for that purpose. Appearently engineers belive automotive engine and automotive automatic transmissions are close enough for small gearboxes likely to be found in small boats like trawlers.

I'm sure much of the above is incorrect but my posting it will probably draw out truths that will be helpful.
 
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Adding to the discussion; I recently bought a Nordic Tug 32 with a Cummins 6 and Twin Disc. The owner's manual and tag on the trans says Caterpillar TO-2 spec oil; none of the engine oils that I can find say that spec or the (superseding) TO-4 spec. Some oil companies, and Caterpillar themselves, make or sell a TO-4 spec trans/driveline fluid at 30 weight, wouldn't that be the best for these transmissions?
 
Adding to the discussion; I recently bought a Nordic Tug 32 with a Cummins 6 and Twin Disc. The owner's manual and tag on the trans says Caterpillar TO-2 spec oil; none of the engine oils that I can find say that spec or the (superseding) TO-4 spec. Some oil companies, and Caterpillar themselves, make or sell a TO-4 spec trans/driveline fluid at 30 weight, wouldn't that be the best for these transmissions?

Shell Rotella 30W lists TO-2

Shell ROTELLA® T1 Heavy Duty Diesel Engine Oil | Shell ROTELLA®

Ken
 
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