Proper gear lube for mercruiser 1 drive

Odegardc

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Hello all, I was looking at some bottles of gear lube I had lying around. One quicksilver bottle has gl-4. And a penzoil lower unit gear lube is a gl-5. Which one do I use for a mercruiser 1 drive. Serial number 4794847. It's a 233 mercruiser engine. I've seen some quicksilver bottles say for less then 75 hp. I haven't seen the ones for more then 75hp. Is there a difference between the two? Thank you.
 

QBhoy

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Quicksilver Premium high performance gear lube...there should be no doubt about this. It's not expensive.
Hope that helps.
 

Bt Doctur

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you can use any 80-85-90W Hypoid, antifoaming, MIL Spec 5, GL-5 rating.
 

HT32BSX115

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you can use any 80-85-90W Hypoid, antifoaming, MIL Spec 5, GL-5 rating.

True statement. I guess I need to keep repeating this, THERE IS NO NMMA MARINE SPECIFICATION FOR HYPOID GEAR LUBRICANT. ZIP ZERO NADA.

So ANY gear lubricant described above is acceptable (most of US like synthetic [NON-limited-slip] oils, like Mercruiser, Volvo, Mobil 1, Am$oil, Valvoline, Brand-x,y,z)

Just ENSURE that you fill the drive exactly as the Manufacturer directs in the OEM manual.
 
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Odegardc

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Thanks for the help. I've only come across the quicksilver fluid rated for less than 75 hp. I however have 233hp. Saw some penzoil gl5. The quicksilver is gl4. Read that the gl5 can corrode brass or white metal ex. Bushings. Any thoughts? Where do you find the quicksilver over 75hp. What's the difference between the hp ratings.
 

QBhoy

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Thanks for the help. I've only come across the quicksilver fluid rated for less than 75 hp. I however have 233hp. Saw some penzoil gl5. The quicksilver is gl4. Read that the gl5 can corrode brass or white metal ex. Bushings. Any thoughts? Where do you find the quicksilver over 75hp. What's the difference between the hp ratings.

Called Quicksilver Premium or high performance gear lube
 

HT32BSX115

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Read that the gl5 can corrode brass or white metal ex. Bushings.


It's not as much the GL-5 rating as much as it's certain EP (extreme pressure) additives. that can cause corrosion.
ASTM actually has a test called the "Copper Strip Corrosion Test" (ASTM D130) I always like to refer to one of my favorite references in lubrication "science" http://machinerylubrication.com/Read/28958/ep-additives-effects

Certified hypoid lubricants are tested using a whole host of ASTM tests (ASTM D130 being one of them) They usually meet or exceed these test requirements or they don't get certification. You certainly don't want your ("yellow" metal) bushings, synchros and cone clutches corroding in any gearbox!
 

Odegardc

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Is there any bronze or brass in lower units that can corrode? It’s from the 70’s so I wouldn’t know. I just have 4 bottles of the pennzoil and didn’t know if I should or shouldn’t use them.
 

Odegardc

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Pre alpha stern drive gear lube

Hey all,
have some pennzoil marine gear lube that is an apu GL-5. Wasn’t sure if it’s ok for my 1977 mercruiser stern drive. It’s on a 233 mercruiser. Quicksilver is all GL-4. Something mentioned about yellow or white metals corroding. Don’t know if any of those metals are inside. Brass or bronze. Thanks for any help. I’d go for quicksilver as that’s what I’ve been using. But had bought these a few years back as they were cheaper. Thanks for any advice.
 

matt167

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some of the shift dogs on the older outboards had yellow metals and GL-4 is what is needed as it won't damage yellow metals.. GL-5 will... I had Quicksilver GL-4 in a 5spd transmission for a Suzuki mini truck as it was cheaper than any other I could find. The syncronizers were bronze, so GL-5 would have destroyed them

Quicksilver high performance is GL5 and is what you need on a stern drive or outboard over 75hp. any old 80w90 GL5 will do though.
 

QBhoy

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True statement. I guess I need to keep repeating this, THERE IS NO NMMA MARINE SPECIFICATION FOR HYPOID GEAR LUBRICANT. ZIP ZERO NADA.

So ANY gear lubricant described above is acceptable (most of US like synthetic [NON-limited-slip] oils, like Mercruiser, Volvo, Mobil 1, Am$oil, Valvoline, Brand-x,y,z)

Just ENSURE that you fill the drive exactly as the Manufacturer directs in the OEM manual.

I’d agree about any good GL5 for the merc alpha. But I also know that quicksilver standard gear oil is pretty much a no no in a VP 290 DP. It tends to not work so well and on occasion makes the cone clutch slip.
 

Odegardc

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I don’t have the manual for the drive. I don’t know what it actually calls for. That might be the best way to go. Does anyone know what it calls for?
 

Scott06

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An older alpha gen one or mc1 drive spec'd the premium gear lube. Back in the day the premium gear lube didn't have the 75 hp max rateing on it. I ran it for many years in my 1990 alpha one gen one with no issues.

I think the 75 hp got put on the premium gear lube when the alpha gen II came out in 1991 which specs the high performance gear lube (which is bluish in color and is a semi synthetic vs brownish non synthetic for premium).

In your drive either will work just fine
 

QBhoy

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An older alpha gen one or mc1 drive spec'd the premium gear lube. Back in the day the premium gear lube didn't have the 75 hp max rateing on it. I ran it for many years in my 1990 alpha one gen one with no issues.

I think the 75 hp got put on the premium gear lube when the alpha gen II came out in 1991 which specs the high performance gear lube (which is bluish in color and is a semi synthetic vs brownish non synthetic for premium).

In your drive either will work just fine

Both quicksilver normal and high performance gear oil is green in colour here in the U.K. weird that it’s different over there ??
 

Scott06

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Both quicksilver normal and high performance gear oil is green in colour here in the U.K. weird that it’s different over there ??

Full disclosure I haven't bought it in five years since I got rid of my alpha gen I , only bought high perf since new boat has a gen 2 so may be same color here.
 
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