primary oil question
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Joined: Jan 2013
Posts: 96
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From: Levelland, Tx
primary oil question
What primary oil is every one using out there? Ive seen alot of diffrent things from 20-50 to trick shift atf. I just removed my primary cover to install forward controls so i need fluid what is best to put in there?
Seasoned HDF Member
Joined: Jan 2008
Posts: 52,957
Likes: 44,476
From: SW OH.
I don't know whats best but I just use HD Syn3 20w50 which is approved by Harley and is the same oil I use in my motor. It's mainly to lube the primary chain so I have no qualms about using it. For my tranny though I use Spectro 6 speed.
Elite HDF Member
Joined: Jul 2007
Posts: 4,749
Likes: 16
From: sand mountain Alabama
Well I am old school so what I do is probably different from most and how I see it.
Stock clutch with mild build I use either 20-50 or HD standard primary/transmission fluids.
The primary is nothing but a oil bath.
Big build trans fluid.
Stock clutch with mild build I use either 20-50 or HD standard primary/transmission fluids.
The primary is nothing but a oil bath.
Big build trans fluid.
Road Warrior
Joined: Mar 2012
Posts: 1,514
Likes: 88
From: USA
I use Mobil 1 full syn 4T 10w40 in mine, but only because I scored some at a good price. Been using it for a few years now and can't say a bad thing about it, great stuff.
A lot of peeps also use Rotella 15w40...
A lot of peeps also use Rotella 15w40...
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Tourer
Joined: Jun 2012
Posts: 320
Likes: 0
From: Meridian, Idaho
I use oil specifically formulated for primary chain life and clutch operation. I believe the inner primary bearing gets lubed by the same oil. I have used it now in 2 different Harleys and noticed improved operation of the clutch and transmission shifting due to clean clutch plate brake-away and reduced primary noise. In my travels and to my knowlege, Bel-Ray Primary Chaincase oil is the only product that is for chaincase use only.
It's the good stuff!
It's the good stuff!
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Seasoned HDF Member
Joined: Dec 2010
Posts: 7,736
Likes: 1,524
From: Coromandel Peninsula New Zealand
I use Valvoline 75W-90 gear oil in the primary (I get it cheap with my trade card at Repco) and Spectro Gear Guard in the tranny because it fits my worldview on what tranny oil should be like......thick, basically :-)
