Synthetic auto trans fluid

[sdowney717]

I thought about using it in a borg warner velvet drive on the boat.
It is a gear reduction with clutch plates, like auto trans are made.
I have read trans run cooler, cooler is good for longer life.
Do you think it would lower friction?
Would you use any less fuel?

Normally I use typical Dexron.

 

[Lou_tribal]

I would say that if you normally use dexron and everything is fine stick with it and you will still be happy as everything will still run fine

L.

 

[kchace]

I thought about using it in a borg warner velvet drive on the boat.
It is a gear reduction with clutch plates, like auto trans are made.
I have read trans run cooler, cooler is good for longer life.
Do you think it would lower friction?
Would you use any less fuel?

Normally I use typical Dexron.

When in forward, everything is locked so the only friction is in the bearings and the assemblies spinning within the oil. My personal concern would be compatibility with the clutch material. Newer transmissions may use a completely different type of material - older type materials may or may not be compatible with newer/synthetic oils.

Ken

 

[psneeld]

Jleonard on this form I believed switched to a synthetic lube, but not sure what.

He rebuilt his own transmission I believe, and has working knowledge of them from an engineering standpoint.

If he doesn't respond...might try a PM.

 

[sunchaser]

The book for your installation says--- ?

Where synthetics really shine is in boats that have a coolant cooled high engine speed gear reducer - transmission with temperatures approaching engine temps. In raw water cooled (mine run below 115F in the PNW) transmissions slow RPM and cooler running transmissions the advantage if any would be hard to quantify, possibly injurious as suggested by kchace.

 

[sdowney717]

The book for your installation says--- ?

Where synthetics really shine is in boats that have a coolant cooled high engine speed gear reducer - transmission with temperatures approaching engine temps. In raw water cooled (mine run below 115F in the PNW) transmissions slow RPM and cooler running transmissions the advantage if any would be hard to quantify, possibly injurious as suggested by kchace.

My book is from 1970. Trans fluids have changed a lot in 50 years.
From what I understand, modern fluids are backwards compatible to Dexron ratings. Dexron 6 is the new Dexron. It does cost more which is why I never used the newer fluids.

 

[Nomad Willy]

I think the most common problem w BW gears is oil seals.

Most or all the early synthetic lube oil problems w seals have been solved so there shouldn't be any problems w the syn gear oil. However from what I've read they put in an additive to counteract the swelling, hardeding or whatever the seal problem was or would still be w/o the additive. Like VI additives I'm sure this additive has little or no lubricating qualities but if there was any mistake in adding the stuff questionable results could happen.

The only reason to use syn is for high heat applications like racing engines or cars/trucks pulling a heavy trailer up a steep mountain pass in the desert. But unless there's something wrong w your equipment temps experienced in slow speed yachts run by old men should be way below the temps that need or benefit from syn lubricants.

Since you don't need it for heat and there's a remote chance it could cause seal problems regular Automotive trans oil is totally adequate and IMO a better choice.

 

[sunchaser]

My book is from 1970. Trans fluids have changed a lot in 50 years.

Hummm, 50 years. Seems like the fluid you have been using and the boat's upkeep have done pretty well.

 

[sdowney717]

I think the most common problem w BW gears is oil seals.

Most or all the early synthetic lube oil problems w seals have been solved so there shouldn't be any problems w the syn gear oil. However from what I've read they put in an additive to counteract the swelling, hardeding or whatever the seal problem was or would still be w/o the additive. Like VI additives I'm sure this additive has little or no lubricating qualities but if there was any mistake in adding the stuff questionable results could happen.

The only reason to use syn is for high heat applications like racing engines or cars/trucks pulling a heavy trailer up a steep mountain pass in the desert. But unless there's something wrong w your equipment temps experienced in slow speed yachts run by old men should be way below the temps that need or benefit from syn lubricants.

Since you don't need it for heat and there's a remote chance it could cause seal problems regular Automotive trans oil is totally adequate and IMO a better choice.

Yes, trans certainly does not get as hot as a car or truck. Every 20* temp drop in them I read doubles their expected life if they experience high temperature running.

I rebuilt one velvet drive myself due to a leak. Rust had built up on cast iron pump body surface causing the black square O-ring to weep fluid. they are very simple inside compared to auto trans construction.

All the seals, rubbers, friction plates were in such good shape, like new, I saved them.
My thinking with synthetic is a friction reduction, so ever so slightly improved HP transfer to the props.
I checked my fluid and it had been a few years. It was a beautiful clear red.
Dexron III, is what I use. The fluid looks so good, I don't think it is worth changing. They are the older style series 72c inline velvet drives with 2.57 to 1 reduction gears.

This month I replaced the shaft coupling with a split one. You can see the bolt on flange in the reduction unit which signifies it is the older style gear reduction.

I like the split coupler so much more. It is beefier, a real strong design. My runout is now .000 to .002 between the flanges. I am hoping that means my shaft is not bent.

 

[Wxx3]

What temperature does your transmission run?

 

[twistedtree]

I have heard that synthetic oil in gears can cause clutch slippage precisely because the oil is slipperier. I think that was with motor oil, but I would have the same concert with ATF.

Perhaps call BW and see what they say?

 

[sdowney717]

I don't have a gauge, but I can keep my hands on them. So maybe 120* tops, just a guess.

 

[Ski in NC]

A more slippery lube is not good in wet clutches. Clutches count on friction to avoid slipping, and slipping burns them up in short order. Make sure the fluid you use is compatible with what was originally spec'd.

I see no advantage to syn in this app.

 

[GoneFarrell]

Synthetic ATF is designed to work with wet clutches, that's what is in all automatic transmissions. For me the main advantage is the stuff has a flatter viscosity curve, cold to hot. Not an issue for normal stock boat transmissions. I think that most people think it is more slippery, because it is not as viscous when cold or in the bottle vs. dino ATF.

I use it for fork and shock oil in motorcycles because the flatter viscosity curve yields more consistent damper behavior cold to hot, works good for that application.

 

[jleonard]

I went with synthetic 5-30 motor oil after a discussion with an "experienced timer" at my local BW distributor.
So far so good after 19 seasons. Temp stays nice and cool too.

 

[pacopico]

Velvet Drive Transmissions use clutch packs from Allison Heavy Duty Transmissions, and therefore in their manual (when I have reviewed it in the past) they refer to Allison Spec TES-295, which calls for Dextron type Automatic Transmission Fluid.

Castrol Trans-Syn is the Allison "standard" Synthetic Transmission fluid, and is suitable for all Allison Automatic Transmissions as it meets the specifications of TES-295.

Take a look in the manual for the transmission...what does it specify?

For what its' worth in Heavy Duty Allison Transmissions (when I left that business 10 years ago) it was required to run Synthetic to keep the 5yr/500,000 mile warranty.

 

[Lou_tribal]

Excuse my question if it is just showing my ignorance but what would be the expected benefit to put syntech oil in a transmission except paying more to get the same? I put syntech oil in my porsche where the engine start turning at 4000 rpm... my boat runs at 1800 rpm at cruising speed, has a tractor engine and the transmission (same has yours) was made when internet was not existing... not sure I understand the expected result or benefit.

L.

 

[Bacchus]

Allison doubled the warranty coverage with syn fluid. They recommend TranSynd. MY Mainship has ZF Trans and TranSynd is on their acceptable/recommended list.
I figured if it's goid for Allison I'd keep boat & motorhome the same...TranSynd for me...not sure what Velvet Drive recommends...I'd check w them.

 

[kchace]

?...not sure what Velvet Drive recommends...I'd check w them.

They recommend Dexron III.

 

[Nomad Willy]

They recommend Dexron III.

No reason to use anything else.

 

[psneeld]

They recommend Dexron III.

They also recommend a variety of oils....such as 30Wt like I run and so does the assistance towboat fleet I work for.

Those boats stress the trannies WAY more than most of us ever do and those trannies last decades.

As long as they are relatively slow turning and the oil doesn't foam....they are suitable lubrication.

 

[Art]

I use Dextron III in both my 71c BW vd trany. Works well, stays clean.

 

[alormaria]

Stick to what has been working well.

 

[catalinajack]

When in forward, everything is locked so the only friction is in the bearings and the assemblies spinning within the oil. My personal concern would be compatibility with the clutch material. Newer transmissions may use a completely different type of material - older type materials may or may not be compatible with newer/synthetic oils.

Ken

Baloney. Read the label. If it meets SAE standards, which it will, it's good to use.

 

[catalinajack]

I have heard that synthetic oil in gears can cause clutch slippage precisely because the oil is slipperier. I think that was with motor oil, but I would have the same concert with ATF.

Perhaps call BW and see what they say?

Baloney. Urban legend.

 

[catalinajack]

The book for your installation says--- ?

Where synthetics really shine is in boats that have a coolant cooled high engine speed gear reducer - transmission with temperatures approaching engine temps. In raw water cooled (mine run below 115F in the PNW) transmissions slow RPM and cooler running transmissions the advantage if any would be hard to quantify, possibly injurious as suggested by kchace.

You had me until you said "possibly injurious". Based on what? All lubricants carry SAE ratings and standards.

 

[sunchaser]

You had me until you said "possibly injurious". Based on what? All lubricants carry SAE ratings and standards.

Boat gear reducers have a few areas where the wrong fluids can prove injurious. Think seals, anti foam, pumps, plates and lubricity. As you correctly state, following the gear manufacturers guidelines for lubricants will prevent possible injury from occurring.

The OP will be well served by following these guidelines. Why mess up a good thing? BTW, baloney on the Internet- never happens.

 

[Nomad Willy]

Many people have the need (seemingly on a par w sexual needs) to use and otherwise align themselves w whatever is new. Many of the new things are or will come to pass as fads and many will be a youthful new and better way of doing things.

Most people get on all the new bandwagons w/o even thinking if it's a good idea. Usually just a knee jerk resopnse to anything considered new. Ever heard the expression "in w the new, out w the old"? It's a psychological need to do the mod things. Anybody who dosn't is some kind of nerd, dufus or just plain dumb person. And of course nobody wants to be seen as dumb or behind the times.

But if there's no need or advantage to new stuff old stuff is not only fine but in many cases better. But on a "feel good" basis most like to go w the new. However there are people that actually think for themselves. Using synthetic lube in a cool running marine gear that uses friction clutches is one of instances where the knee jerk get on the new bandwagon move is not good.

However if a manufacturer recommends it (the new stuff) it's probably fine. I say just probably fine because at times manufacturers recomendations don't cover or consider all circumstances. But to make new things good there must be some real benefit.

Didn't edit.

 

[jleonard]

My engineer co-workers who dealt with bearings did not like applications that used tranny fluid. It did not lubricate very well thus reduced life.
That was my motivation in addition to velvet drive spacing motor oil as an alternative in applications that were 2600 rpm or less.
My tranny is happy.

 

[Art]

My engineer co-workers who dealt with bearings did not like applications that used tranny fluid. It did not lubricate very well thus reduced life.
That was my motivation in addition to velvet drive spacing motor oil as an alternative in applications that were 2600 rpm or less.
My tranny is happy.

What do your engineer co-workers say to use for trany fluid regarding over 2600 rpm... like 3600 rpm?

I take it you are referring to engine rpm, not drive shaft rpm due to trany reduction.