Oil Change
Supporter
Joined: Jan 2007
Posts: 15,788
Likes: 5,625
From: along the shore of Mishigami
I see a problem in the future. If dino oil has been used for 70K miles, I'd be afraid the syn. would wash away any varnish or deposits and then some gaskets would start weeping/leaking.
Grand HDF Member
Joined: Sep 2013
Posts: 3,820
Likes: 588
From: Michigan
There's nothing wrong with a high quality petroleum based oil ("dyno" oil) with a good additive package. However oils with a Group IV base stock (full synthetic) tend to perform better when subjected to extreme temperatures. And high quality synthetics, because of production costs, generally have very good additive packages to allow them to be marketed as premium product.
As a footnote, Chevrolet's flagship vehicle, the C7 (Corvettes with high performance, high output engines) are delivered with Mobil 1 full synthetic as the factory fill oil.
Differing opinion, (and I respect your opinion & valued contributions to HDF), but I run full synthetic engine oils (not all the same brand or API rating) in all of my vehicles, (bikes, trucks & cars). Without any reservations.
Seasoned HDF Member
Joined: Jan 2011
Posts: 157,518
Likes: 57,070
From: Michigan 15 Minutes East Of Hell
After 36 years working in the Fuels & Lubricants Department of GM's Research Labs, I would recommend either a full synthetic or synthetic/petroleum blend oil. I've heard lots of "old school" stories about synthetics being "too slippery" for H-D motors. Total "hog wash" (pun intended).
There's nothing wrong with a high quality petroleum based oil ("dyno" oil) with a good additive package. However oils with a Group IV base stock (full synthetic) tend to perform better when subjected to extreme temperatures. And high quality synthetics, because of production costs, generally have very good additive packages to allow them to be marketed as premium product.
As a footnote, Chevrolet's flagship vehicle, the C7 (Corvettes with high performance, high output engines) are delivered with Mobil 1 full synthetic as the factory fill oil.
Differing opinion, (and I respect your opinion & valued contributions to HDF), but I run full synthetic engine oils (not all the same brand or API rating) in all of my vehicles, (bikes, trucks & cars). Without any reservations.
There's nothing wrong with a high quality petroleum based oil ("dyno" oil) with a good additive package. However oils with a Group IV base stock (full synthetic) tend to perform better when subjected to extreme temperatures. And high quality synthetics, because of production costs, generally have very good additive packages to allow them to be marketed as premium product.
As a footnote, Chevrolet's flagship vehicle, the C7 (Corvettes with high performance, high output engines) are delivered with Mobil 1 full synthetic as the factory fill oil.
Differing opinion, (and I respect your opinion & valued contributions to HDF), but I run full synthetic engine oils (not all the same brand or API rating) in all of my vehicles, (bikes, trucks & cars). Without any reservations.
Are you out of the Proving Grounds in Milford? My oldest son is a PIpe/Steam fitter that frequents the grounds ( been there for the last 18 months this time )
Road Warrior
Joined: Nov 2014
Posts: 1,962
Likes: 140
From: NY
Just an FYI for those that aren't aware & or those that would like to know why full syn oil will sometimes (not always) leak in a motor/trans where std dino oil used prior didn't leak or seep.
From what i understand it's because on a molecular level the molecules in std dino oil are a bit larger & not of equal shape and size vs the molecules full syn oil is made of being a bit smaller and more evenly sized therefore making it easier for full syn oil to get past seals/gaskets
That's more of an issue when used in a motor that's got some age & or miles on it where the gaskets/seals may have shrunken & or cracked due to heat,age & exposure to oil & it's additive pkg chemicals in a harsh hot operating environment for multiple yrs & miles.
So by design full syn oil being a bit more slick then std dino along with it also having smaller more evenly sized molecules collectively together allow it to more easily leak & or seep past gaskets/seals etc where std dino didn't leak in the same motor/trans/app.
Happy Motoring.
Scott
From what i understand it's because on a molecular level the molecules in std dino oil are a bit larger & not of equal shape and size vs the molecules full syn oil is made of being a bit smaller and more evenly sized therefore making it easier for full syn oil to get past seals/gaskets
That's more of an issue when used in a motor that's got some age & or miles on it where the gaskets/seals may have shrunken & or cracked due to heat,age & exposure to oil & it's additive pkg chemicals in a harsh hot operating environment for multiple yrs & miles.
So by design full syn oil being a bit more slick then std dino along with it also having smaller more evenly sized molecules collectively together allow it to more easily leak & or seep past gaskets/seals etc where std dino didn't leak in the same motor/trans/app.
Happy Motoring.
Scott
Seasoned HDF Member
Joined: Jan 2007
Posts: 20,616
Likes: 4,440
From: anacoco, la
harleys are delivered with hd360, with the exception of the screamin eagle bikes, they come from the factory with syn3 in them.
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Grand HDF Member
Joined: Sep 2013
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From: Michigan
Not now. Took an early retirement package back in 2008. Worked in Bldg 42B.
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From: in a cave at the foothills
