Quicksilver 5W30 for all sterndrives

[jonny rotten]

Quicksilver 5W30 for ALL sterndrives. What happened to only using 25w40? I've been using 5w30 full synthetic oil for the last few years in my 4.3. This debate has been going on forever and now Quicksilver which is synonymous with Mercury is making a lower viscosity oil for Mercruisers...has it all been smoke and mirrors with Mercury's exclusive 25w40 blend?

https://www.googleadservices.com/pa...YTUvsz-AhUDk4kEHbFhDDEQ9aACKAB6BAgEECI&adurl=

 

[alldodge]

Oh no another oil thread


V8 Verado requires 10W30 Syn blend

 

[Lou C]

It is a full syn, maybe they think that means it is OK. V/P used to specify a full syn 10w/40.
I think it maybe ok in outboards since they tend to spec lighter weight oils, the old style GM marine inboards tend to shear down lighter oils more so I'd stick with 25/40, or even 20/50 for those.
I always say use what you want but do a few used oil analyses that way you'll know if the oil is good enough for your use.

 

[Scott Danforth]

Mercruiser doesnt warranty past 5 years.

on the old GM based motors, I would keep up with 15W40 or 25W40
on the new Mercruiser designed motors they still are calling out for 25W40

Mercury Precision Marine Motor Lubricants | Mercury Marine

Marine oils and lubricants - Mercury Precision Lubricants® are specially formulated for the unique needs of marine engines. They are rigorously tested to original-equipment manufacturer standards to help protect and extend the life of your engine.

www.mercurymarine.com

My guess there is a label issue and it should read 4-stroke outboards.

 

[alldodge]

The 6 cyl verado uses 25W40, the 8 cyl uses 10W30
This is the reason I have 6 gal of 25W40 and 6 gal of 10W30, bought the wrong stuff at first.

 

[Bondo]

Quicksilver 5W30 for ALL sterndrives.

Ayuh,....... I run nothing but 75W-90 full-syn oil in my drives,......

I run 15W-40 diesel motor oil in all my motors,......

 

[jonny rotten]

Ayuh,....... I run nothing but 75W-90 full-syn oil in my drives,......

I run 15W-40 diesel motor oil in all my motors,......

I always ran Rotella T6 15w40 for years. The 5w30 seems to crank and start easier which is a good thing. I was worried about the thinner oil but havent noticed any bad effects. The oil at the end of the season was still golden after a few WOT runs last year which I normally avoid but was feeling confident in my old 4.3. Now I see Quicksilver is recommending thinner oil which makes me feel better

 

[tpenfield]

I get the 25W-40 that is CAT friendly

 

[ScottinAZ]

my guess, is that the change, much like with autos is emissions related. Thinner oils contribute (minutely) to lower emissions due to less parasitic and pumping losses...... they dont care about longevity as long as it makes it past the warranty period, but with the EPA up everyones ass about emissions, it makes a difference to the MFG. I just stick with what works... 15w-40 in the boat...

 

[TomB985]

I’ve run Rotella 15w40 for years because it’s inexpensive and proven to perform well. I used to get into long oil discussions on BITOG and a couple of truck forums before realizing just how little it mattered.

It’s pretty rare to hear of a lubrication-related failure. And when you do, it’s almost universally the result of lack of maintenance rather than picking a different viscosity. I wouldn’t run Toyota-spec 0w-16 in the boat, but you could probably use it without ever experiencing an issue. I haven’t forked out the money for UOA in about ten years because I just don’t see the point anymore.

The boat’s owner usually cares more about oil than the engine does. Just remember to change it once in awhile.

 

[ScottinAZ]

I’ve run Rotella 15w40 for years because it’s inexpensive and proven to perform well. I used to get into long oil discussions on BITOG and a couple of truck forums before realizing just how little it mattered.

It’s pretty rare to hear of a lubrication-related failure. And when you do, it’s almost universally the result of lack of maintenance rather than picking a different viscosity. I wouldn’t run Toyota-spec 0w-16 in the boat, but you could probably use it without ever experiencing an issue. I haven’t forked out the money for UOA in about ten years because I just don’t see the point anymore.

The boat’s owner usually cares more about oil than the engine does. Just remember to change it once in awhile.

more equipment has been killed by no oil than ever has by the WRONG oil....

 

[Lou C]

In the case of I/Os I think the main causes of engine failure are under maintained cooling & exhaust systems…overheating & water intrusion.
Oil is probably a cause only when you have a dramatic failure like a blown remote oil filter hose or rotted thru oil pan.
That said I won’t use an oil that shows anything less than 20-25 psi on the gauge after running in plane…

 

[Searay205]

Yes smoke and mirrors, and Santa Clause is in the eyes of the beholder.....

 

[tpenfield]

If you are going off of the oil product advertisement literature as saying that the oil spec's for all engines have changed . . . Don't.

Particularly if you are going with a lower viscosity oil than what the engine manufacturer originally recommended.

Pass the popcorn please