Synthetic or conventional drive lube.

[MacGyver]

What are you running?

[smittyseng]

I found that the amsoil synthetic combined with cryo treating/proper gear surface prep seems to give the best life of the gears under extreme hp situations. I tested alot of gears with royal purple and after switching to amsoil have realized it works better. Merc hp is fine for stock boats but I had no luck with gears using it,Smitty

[Chris]

I found that the amsoil synthetic combined with cryo treating/proper gear surface prep seems to give the best life of the gears under extreme hp situations. I tested alot of gears with royal purple and after switching to amsoil have realized it works better. Merc hp is fine for stock boats but I had no luck with gears using it,Smitty

Are you using isotropic micropolishing on the gear sets? If so, have you tried the REM process?

[Geronimo36]

I found that the amsoil synthetic combined with cryo treating/proper gear surface prep seems to give the best life of the gears under extreme hp situations. I tested alot of gears with royal purple and after switching to amsoil have realized it works better. Merc hp is fine for stock boats but I had no luck with gears using it,Smitty

Smitty,

Who does the treatments in our area (NJ)? I have one of my lowers apart with about 20 hours on new gears so I figure it would be a great time to get the treatment done since the gears have taken a "set".

I also use the Amsoil gear lube. Are you using the marine lube or the severe gear?

[runninhotracing]

Ditto Amsoil gear lube on the wett sumps

[smittyseng]

[QUOTE=Chris;8276]Are you using isotropic micropolishing on the gear sets? If so, have you tried the REM process?
Among other things,the gear treatment field is constantly evolving,Smitty

[smittyseng]

Smitty,

Who does the treatments in our area (NJ)? I have one of my lowers apart with about 20 hours on new gears so I figure it would be a great time to get the treatment done since the gears have taken a "set".

I also use the Amsoil gear lube. Are you using the marine lube or the severe gear?

I don't know who does the gears in the Jersey area but there are many places thru-out USA.I have a shop that I work exclusively with that does my gear treatments,it's a multi step process,we have experimented with different treatments and processes to try to find the most durability. I'm using the severe gear Amsoil,I'm very happy with it. You can pm me if interested in getting gears done,Smitty

[Tomas Wallin]

I'm using cryo'ed gears and Royal Purple 75W90 and oil cooler, filter and circulation pump (From Mr Gadgets/Dick)). Still during break in with 6.5 hours.

Replaced the filter after 4.5 hours and there was pretty much debris in it and that was from 0-4000rpm with no boost. I will change the filter after another 1-2 hours since I'm putting on some boost now.

The cooler and filter seems to works very good! :seeya:

[Geronimo36]

I don't know who does the gears in the Jersey area but there are many places thru-out USA.I have a shop that I work exclusively with that does my gear treatments,it's a multi step process,we have experimented with different treatments and processes to try to find the most durability. I'm using the severe gear Amsoil,I'm very happy with it. You can pm me if interested in getting gears done,Smitty

Smitty, sorry for the confusion, I didn't look at your location and assumed you were Smitty from OPA, NJ.

Regardless, thanks for the info.

[Boater8987]

synthetic= Alisyn 80W

[Move'n Up]

Amsoil AGM - Marine Gear Lube

[Hot for Teacher]

Torco Synthetic RTF

[shifter]

Synthetics = twice the cost, half as good.

We went out and made some of our own. My brother did the logo, look for the W. It is a mineral base with one additive.

If you are running a wet-sump... High temp type oil (green or yellow).

If you are running a merc dry-sump (ie fake drysump).... see above.

If you are running a weismann dry-sump...... mineral base 30 wt gl5/gl6

pick your poison.

pat W

[Hot for Teacher]

Nice Fangs, Pat....

[OldSchool]

I run the HP Merc stuff in my wet sump 6's.

[Formula 382 sr-1]

Ditto Amsoil gear lube on the wett sumps

Yup us too !!!

[CignificantOther]

I run the HP Merc stuff in my wet sump 6's.


Ditto for my wet sump 6's

[dykstra]

synthetic

[Mr Gadgets]

I have been running Royal Purple with Prolong engine treatment added for 12yrs or so..

[ar15meister]

I run the HP Merc stuff in my Imco. No problems yet.

I would have thought more guys would be using Merc stuff.

[smittyseng]

I WAS running Royal purple for a few years among other oils I tested and switched to Amsoil this year. I tested additional heat treatments,coatings and various cryo treatments and have been able to extend my gear service life on bravo lower gears with some processes but the amsoil seems to have helped the lower gear life signifigantly over the royal purple so even though it's cheap and convienient for me to get I no longer run it,Smitty

[Mr Gadgets]

All I can say Smitty is that I have not had a failure with my drive. Although I am at much lower hp (700-750hp) than you are. Hopefully that will change this year. With over 300hrs on my drive at this point. I can not knock the RP.
I have a drive ready to go on the boat with a lower set of gears that have a magic coating on them, suppose to be the answer. We'll see. If the coating shows any signs of benifit, I will add the cryo treatment to it and see how that works out. Just have to get the new motor together.
The drive also has my version of external cooling and filtering, so drive temps will be in the 140* range, which is good for any lube to operate it in the recommended temp range.
Dick

[glassdave]

Dick i am curious about the cooler/filter system you have. what kind of temps do they run with and without it? is it inside the drive or outside? pics? Do you do the conversion or offer a kit? Sounds pretty cool i didnt know you had something like this. I run HP Bravos on the Donzi and have had pretty good luck but she is heavy and any things gotta help. I dont baby the boat but i also dont beat it. Had my first drive failure since new but that was kinda my fault. I keep up on service intervals but think i missed the left hand drives cap bolts walking out and she may have ingested some water taking out the upper gears (thats just my thought but i'm no drive guy :D). Only wiped a few teeth and the shrapnel was mostly fine pieces.

[Chris]

http://www.drewmarine.com/products/coolswirl/coolswirl.html

Drew makes a setup- probably duplicable for a few less bucks.

[Mr Gadgets]

Dave,
My setup is similar to Drew's, except I use a differnt pump, add a filter and remove the oil from a different place and inject it at a different place. I have a list of parts, with all the fittings and hoses and components and drilling the case, it gets real close to the $1k mark. I have not been able to test the setup on my own boat. This year I will and will have some data to share. At this point I do have a couple of drives out there with it installed. One customer told me he wasnt sure it was working. I told him to leave the pump off and see what happend to drive temps.. when they hit around 200* he turned on the pump and the temp dropped to 140* within a min. So it is a work in progress. Drew's system is comparable. I added a filter and when you cut it open, you can see just how much metal a Bravo produces, and all that is circulated thru the preloaded tapered bearing. The main difference is that I pull the oil from the lower and inject it into the upper pointing at the pinion gear. I perfer to do the modification to the case, which needs to be stripped down in order to do it. So I have not been offering a kit, due to the complexity of the case modifications. But if some one has no quams about taking a drill to a $1400 upper case, I could surely include some instructions..
Here is picture of my kit that I have put together. It is all top quality hoses and fittings. Outside is SS and inside is Aeroquip An hose and Fittings..

On another note, the top cap bolts shouldnt be backing out. Most of the time, the gear breaks and pushes them out. I use the XR top cap and a stud kit that I put together to help that LH drive out..

[LAKE EFFECT]

Amsoil severe gear with 10% Lucas heavy duty oil stabilizer(non syn), per Max Machine Worx.

Mr Gadgets,
Is the 100 degree drop with or with out a drive showers? Sounds like a great upgrade.

LE

[Mr Gadgets]

Without the external drive shower.

[Tomas Wallin]

Dave,
My setup is similar to Drew's, except I use a differnt pump, add a filter and remove the oil from a different place and inject it at a different place. I have a list of parts, with all the fittings and hoses and components and drilling the case, it gets real close to the $1k mark. I have not been able to test the setup on my own boat. This year I will and will have some data to share. At this point I do have a couple of drives out there with it installed. One customer told me he wasnt sure it was working. I told him to leave the pump off and see what happend to drive temps.. when they hit around 200* he turned on the pump and the temp dropped to 140* within a min. So it is a work in progress. Drew's system is comparable. I added a filter and when you cut it open, you can see just how much metal a Bravo produces, and all that is circulated thru the preloaded tapered bearing. The main difference is that I pull the oil from the lower and inject it into the upper pointing at the pinion gear. I perfer to do the modification to the case, which needs to be stripped down in order to do it. So I have not been offering a kit, due to the complexity of the case modifications. But if some one has no quams about taking a drill to a $1400 upper case, I could surely include some instructions..
Here is picture of my kit that I have put together. It is all top quality hoses and fittings. Outside is SS and inside is Aeroquip An hose and Fittings..

On another note, the top cap bolts shouldnt be backing out. Most of the time, the gear breaks and pushes them out. I use the XR top cap and a stud kit that I put together to help that LH drive out..

I will also test this system very well next year. So far it's installed and have been running it for 5 hours but my oil temp sender or gauge won't work so I dont have any numbers yet.

Pics of the rigging of the DPM drive and oil system

[Tomas Wallin]

More pics

[phragle]

totally different aplication, but it really sold me on Amsoil, desert atv racing. little aircooled 2 stroke from the factory, made 15 hp. Using yamaha's recom. lube I wasnt getting 24 hours out of a tranny. exploded a gear hear and there but for the most part, the gears were just plain wearing out. few more engine mods and pushing 50 hp, with amsoil and shotpeening gears they are holding up to the added power great. I have the same thing to say about their 2 stroke oil. after the 24 hour race with the motor making about 30 hp using trick 112 and yamalube r the top end was toast, did another 24 hour race with a 35 hp motor ( and this top end was used not new) usuing amsoil and trick the motor had the same compression at the end as it did at the beginning and looked good at tear down.

[Mr Gadgets]

Tomas,
that is one sweet lookin boat!! The setup for the oil cooler looks very nice!

Thanks!
Dick

[07DominatorSS]

What are you running?

AMSOIL marine 75/80w-90 gearlube in my Bravo 1X's!!!

[07DominatorSS]

Amsoil severe gear with 10% Lucas heavy duty oil stabilizer(non syn), per Max Machine Worx.

Mr Gadgets,
Is the 100 degree drop with or with out a drive showers? Sounds like a great upgrade.

LE

In my opinion, you shouldn't add any addtives to the oil. If it was meant to be in there, it would already be in there. Company's spend multi millions of dollars getting the "recipe" perfect, and if some outside agent is added, it can throw that perfect mix of additives off, possibly causing premature wear or shearing of the oil.

Think about your grandmothers famous recipe, whether its a cake or whatnot, if you were to add a little extra of some ingredient, it wouldn't turn out right, now would it? Kind of the same idea.

[Mr Gadgets]

O7 you are correct!! Not good to add things. But, I heard this recipe from a guy 15yrs ago.. been doing it ever since and not found a problem.. cake tastes the same every time..
Do I have enough power to destroy a drive, not sure? Is the mix helping.. not sure till I break my drive. Am I going to leave out the extra till I break it and see if adding it helps.. not!
Sorry.. I just keep doing what I do. I dont have any scientific studies to prove or disprove the combination.

Dick

[LAKE EFFECT]

In my opinion, you shouldn't add any addtives to the oil. If it was meant to be in there, it would already be in there. Company's spend multi millions of dollars getting the "recipe" perfect, and if some outside agent is added, it can throw that perfect mix of additives off, possibly causing premature wear or shearing of the oil.

Think about your grandmothers famous recipe, whether its a cake or whatnot, if you were to add a little extra of some ingredient, it wouldn't turn out right, now would it? Kind of the same idea.

I'm not going to get enough time on my drives to know if the Lucas stabilizer helped or hurt when I break one. But I do trust Aaron at Max, they sell good parts, and run alot of high HP Bravo combos. So if he says they have had good luck with the mix, I'm in. Plus I did test out the Lucas addititive before using it, and it is some sticky clingy stuff, and I'm sure it does add to the cushining affect on the gears.

LE

[07DominatorSS]

I'm not going to get enough time on my drives to know if the Lucas stabilizer helped or hurt when I break one. But I do trust Aaron at Max, they sell good parts, and run alot of high HP Bravo combos. So if he says they have had good luck with the mix, I'm in. Plus I did test out the Lucas addititive before using it, and it is some sticky clingy stuff, and I'm sure it does add to the cushining affect on the gears.

LE

See that is what people think you are supposed to have, clingy gearlube. That is completely false. You do what you want to do, but having, as you call it, "clingy" gearlube, causes a condition known as fluid friction, which causes unnecessary heat and drag. When gearlube gets thick and sticky as you say, it actually has more difficulty getting in between the gears. Think about it. What would get between two tight together pieces of metal easier, syrup or olive oil. Just my .02.

[HotPursuit]

Mineral oil is for lawn mowers and weed eaters!!:26:

Amsoil is the ticket. With twins its easy to do comparisons!!
35 yrs amsoil has been around and has kick as* in independent testing year after year.

[HotPursuit]

totally different aplication, but it really sold me on Amsoil, desert atv racing. little aircooled 2 stroke from the factory, made 15 hp. Using yamaha's recom. lube I wasnt getting 24 hours out of a tranny. exploded a gear hear and there but for the most part, the gears were just plain wearing out. few more engine mods and pushing 50 hp, with amsoil and shotpeening gears they are holding up to the added power great. I have the same thing to say about their 2 stroke oil. after the 24 hour race with the motor making about 30 hp using trick 112 and yamalube r the top end was toast, did another 24 hour race with a 35 hp motor ( and this top end was used not new) usuing amsoil and trick the motor had the same compression at the end as it did at the beginning and looked good at tear down.

My son ran a 28 ft cat with twin 2-stoke V-8s and hated the smoking,He tried the 100:1 mix from amsoil and they ran great stop fouling plugs and no more smoking. Plus picked up some rpms.
The only way we could get #3s to live on the Shadow Cat with 1150 hp was to run Amsoil synthic, we burnt up many gear sets and bearings with factory green crap.

[LAKE EFFECT]

See that is what people think you are supposed to have, clingy gearlube. That is completely false. You do what you want to do, but having, as you call it, "clingy" gearlube, causes a condition known as fluid friction, which causes unnecessary heat and drag. When gearlube gets thick and sticky as you say, it actually has more difficulty getting in between the gears. Think about it. What would get between two tight together pieces of metal easier, syrup or olive oil. Just my .02.

You very well might be right about old thick and worn out gear lube, but I dont think thats the situation with the Lucas. The Lucas gets on a surface and doesnt come off, so its not fighting to get back on the gear, its already there. Plus I'm talking about a 10% mix with the Amsoil, so it shouldnt fight against the engineering of the gear lube. Both products are name brand, and both are advertised in high performance applications.

Believe me I am not a sheep when it comes to my boats and cars high performance setups, I use my common sense, my research, and my experiences, plus others experiences and suggestions, throw it together, and see what happens. Sometimes the turn out is good, sometimes bad. High performance boating(and cars) is not a proven art, there is alot of experimenting, and my wallet is only so deep, I need to trust some people, and believe me, the number is small.

LE

[smittyseng]

I'm not going to get enough time on my drives to know if the Lucas stabilizer helped or hurt when I break one. But I do trust Aaron at Max, they sell good parts, and run alot of high HP Bravo combos. So if he says they have had good luck with the mix, I'm in. Plus I did test out the Lucas addititive before using it, and it is some sticky clingy stuff, and I'm sure it does add to the cushining affect on the gears.

LE
They told me the same thing except aaron made it sound like the mixture was closer to 25%,I switched to amsoil this year and have been using the lucas added to it too and so far haven't came close to burning the gears up the way I used to with royal purple. Max machine worx claims they have tried every kind of gear oil looking for the most gear life/drive life,they even used to sell the alysin stuff and some other exotic stuff,now they say don't waste your money,the best stuff they have seen is amsoil mixed with lucas. I believe them because they are not trying to sell the oil,just sharing what Ive been told and tried,Smitty

[Z06]

Amzoil Marine Gear Lube!

[LAKE EFFECT]

They told me the same thing except aaron made it sound like the mixture was closer to 25%,I switched to amsoil this year and have been using the lucas added to it too and so far haven't came close to burning the gears up the way I used to with royal purple. Max machine worx claims they have tried every kind of gear oil looking for the most gear life/drive life,they even used to sell the alysin stuff and some other exotic stuff,now they say don't waste your money,the best stuff they have seen is amsoil mixed with lucas. I believe them because they are not trying to sell the oil,just sharing what Ive been told and tried,Smitty

Aaron told me they add 2qts of Lucas to a 5 gallon container of Amsoil. 5 gallons is 20qts x 32oz = 640oz/64oz=10%. Thats the math I used. Aaron never gave me a %, he just gave me the 5gal/2qt thing. Maybe there experimenting with different percentages??

LE

[smittyseng]

Aaron told me they add 2qts of Lucas to a 5 gallon container of Amsoil. 5 gallons is 20qts x 32oz = 640oz/64oz=10%. Thats the math I used. Aaron never gave me a %, he just gave me the 5gal/2qt thing. Maybe there experimenting with different percentages??

LE

When I talked to aaron he told me add a quart of lucas to a few quarts of amsoil so thats what I been doing,sometimes when you talk to them guys they don't give you exact answers;),Smitty

[go4broke]

I'm running mobil 1 gear lube. Costs the same and mercs conventional hp gear lube. In amsoils tests best lubes were:
1-amsoil
2-mobil 1
3-gm synthetic
http://www.amsoil.com/products/gearlubes/WhitePaper.aspx

lots of interesting info. I chose mobil because it is reasonable $ and easy to find. Plus I already had a few cases!

[go4broke]

Whats the difference between Universal Synthetic Marine Gear Lube and Severe Gear 75W-90? Prices aren't bad, if only you could get it at walmart!

[smittyseng]

I don't know what the real difference is but I'm using the severe gear as that was what was recomended to me by max worx,Smitty

[MOBILEMERCMAN]

I'm running mobil 1 gear lube. Costs the same and mercs conventional hp gear lube. In amsoils tests best lubes were:
1-amsoil
2-mobil 1
3-gm synthetic
http://www.amsoil.com/products/gearlubes/WhitePaper.aspx

lots of interesting info. I chose mobil because it is reasonable $ and easy to find. Plus I already had a few cases!

I am afraid to use Mobil1 in gearcases. Mobil1 make no reference to marine use in their product description. A good marine gearlube has things to tolerate
moisture and water intrusion.

I use Mobil1 engine oil religiously. I use Merc or Amsoil gearlube only. Customers choice.

[go4broke]

I don't know about the gear lube, but I remember one of the benefits of the motor oil was a good tolerance to water intrusion.

[07DominatorSS]

Whats the difference between Universal Synthetic Marine Gear Lube and Severe Gear 75W-90? Prices aren't bad, if only you could get it at walmart!

The difference is that the Marine Gear Lube has Less Sulphur in it, which is an anti wear additive. Excess sulphur can have an adverse effect on soft yellow metals that are sometimes used in Marine Gear Cases. The Marine Gear Lube is a GL-4 and the Severe Gear is a GL-5. GL-4 has less Sulphur.

[go4broke]

Thanks 07.

[RumRunner]

I can’t imagine running anything non synthetic ever…

Now when it comes to the Lucas stuff, anything I’ve ever used from them has always worked flawlessly. With that being said as said before I usually try to avoid anything that is sticky inside any type of engine or gear case. It robs power, and can hold the grime and debris next to the parts you’re trying to protect.

In the race engines I deal with the oil is so thin it’s not even funny, nothing sticky EVER… Heck we’ve backed up to 2WT oils now a days:biggrinjester:

[Rik]

Amsoil?

My U.J.'s run in a bath of oil. Some of the Arnesons use ordinary ATF fluid and I have a customer that swore by Amsoil b/c it lowered the temps on his Bravos.

After 250 hrs with 850 hp blower motors I went through the drives to check things out. (Boat is a 382 Formula and it is loaded = heavy)

U.J. bearings with the ATF fluid looked better than the ones that ran in Amsoil. Both were still good, but the customer used ordinary no name brand ATF fluid in one drive and the Amsoil in the other drive.

As for an Arneson, my belief is .... Oil is Oil. I tell customers to use Merc as they either have it or can get it and it separates the water out if they loose a seal.

I prefer the Mobil 1 Gear oil simply due to nothing more than availability. There is a Grainger in most any town in the US. They carry Mobil 1 Gear oil so it makes acquiring it very easy for anyone.

I get 8-12 thousand hours before rebuilds on drives using nothing more than a standard Mineral 80-90 wt oil also. So go figure.

As far as Bravo's ? I have no experience on what works.

[LAKE EFFECT]

Amsoil?

My U.J.'s run in a bath of oil. Some of the Arnesons use ordinary ATF fluid and I have a customer that swore by Amsoil b/c it lowered the temps on his Bravos.

After 250 hrs with 850 hp blower motors I went through the drives to check things out. (Boat is a 382 Formula and it is loaded = heavy)

U.J. bearings with the ATF fluid looked better than the ones that ran in Amsoil. Both were still good, but the customer used ordinary no name brand ATF fluid in one drive and the Amsoil in the other drive.

As for an Arneson, my belief is .... Oil is Oil. I tell customers to use Merc as they either have it or can get it and it separates the water out if they loose a seal.

I prefer the Mobil 1 Gear oil simply due to nothing more than availability. There is a Grainger in most any town in the US. They carry Mobil 1 Gear oil so it makes acquiring it very easy for anyone.

I get 8-12 thousand hours before rebuilds on drives using nothing more than a standard Mineral 80-90 wt oil also. So go figure.

As far as Bravo's ? I have no experience on what works.



Sorry if I sound stupid but what are U.J.'s. Also, Arnesons get thousands of hours before rebuilds, or was that a typo??

I hate to say it because I'm dependent on the Merc stuff, but the reason why the fluid in the Bravo is so important is because they were under engineered from the get go(1987), and every little thing helps and is needed to get them to survive the HP people(including Merc) are putting to them. I use to run TRS's, and those drives were over engineered for there applications, and if Merc would have thrown some upgrades at them way back when, the high performance boater would be better off. The NXT 1 drive has alot of similarities to the now old and outdated TRS, but costs what to buy(30,000+). Merc could of easily redesigned the drawbacks of the TRS(lower units) and had a great drive that is affordable to the public and profitable to Merc. I know Merc makes some great stuff, and like any company, they are in business to make money. But because they have a monopoly on the market, they charge more than a premium on all there products. Of course this is just my opinion, and sorry for the rant, but I added up what its going to cost to go thru my drives for next season, and its a little disturbing...

LE

[Rik]

U.J. is a Universal Joint

No typo, the typical fishing boat up in Alaska gets roughly 8,000 to 12,000 hours on them before they take the drives off the boat and change bearings and seals. Some get more. The patrol boats are the same way.

They use any oil they can get their hands on, probably whale fat for all I know. We recommend just generic 80-90 wt gear oil like what is used in your car transmission or rear diff.

[LAKE EFFECT]

U-joints, that makes too much sense now that I think about it. Obviously the Arneson is an over engineered piece.

LE

[2112]

FWIW, I just picked up a modified rear axle for my GT500 which included new gears. The shop specializes in ultra custom 9 inch style rear ends taking thousands of horses (race applications)

The Warranty was only good If I continued to run TORCO GL-6 gear oil. According to this shop, most all the big name drag racers are running this now.

Torco is Dino oil BTW.

[Offshoredrillin]

U.J. is a Universal Joint

No typo, the typical fishing boat up in Alaska gets roughly 8,000 to 12,000 hours on them before they take the drives off the boat and change bearings and seals. Some get more. The patrol boats are the same way.

They use any oil they can get their hands on, probably whale fat for all I know. We recommend just generic 80-90 wt gear oil like what is used in your car transmission or rear diff.
You must remember that additive for rear ends then, it was made from sperm whale oil, stunk like hell but worked.

[2112]

In case anyone is interested;

http://www.torcousa.com/technology/060912113038RGO.pdf

.

[2112]

You must remember that additive for rear ends then, it was made from sperm whale oil, stunk like hell but worked.

I was standing there when my Rear end Man added the Ford rear end additive and you are not kidding, man the smell was repulsive. :leaving:

[Rik]

You must remember that additive for rear ends then, it was made from sperm whale oil, stunk like hell but worked.

No, we do not have a 'Ring and Pinion" design so I don't know anything about that. Sounds to funny not to be true though.

[smokinbob]

synthetic= Alisyn 80W

I can't say enough about Alisyn, great product. I'm alway's surprised at how clean the lube is with barely any "fuzz" on the magnet. Running XR's w/IMCO lowers behind 800+HP.

[Bobcat]

:seeya:

[ryan9154]

I was running royal purple switched to amsoil severe gear.Ran one drive with royal, one with amsoil gears looked brand new with the amsoil,other ones were fine but had some discoloration,ran for 62 hrs like that before I took them apart.Running 702 hp with upgraded bravos 280 hrs on them.Amsoil all the way!!!Buy it in bulk can ship anywhere.

[Wobble]

Mobil 1 Synthetic Gear Lube LS 75W-140

I fail to see why "marine" is important, it's not that hard to seal an outdrive. Otherwise it's just a gearbox

[Back4More]

I ran Mobil 1 75-90 with a lucas mix at about 10-15% for the last season and a half on cryo gears I bought from Smitty. I broke a lower vertical shaft last week and had the chance to open it up for inspection. The gears had almost no wear and the bearings looked good with exception to the propshaft gear bearing....by far the highest load carrier. The cryo was well worth the dime and I will never change from this Gear Lube recipe. This was on a 1993 non step/tank 42' Fountain, 800+ HP blower motors, 1.3 Bmax uppers with IMCO -2 lowers, on IMCO boxes, spinning 4 Blade bravo1 props.