Syn 3 or no?
Road Master
Joined: Mar 2013
Posts: 1,151
Likes: 14
From: Seattle
As I stated a few posts ago, I use the 15/50 synthetic Mobil 1 and it's fine. The special motorcycle formula that so many people use is really for bikes that have "one hole" for all fluids because it is designed to work with the clutch too. Because our crank and clutch are separate, we don't need to worry about it. Of course many on this board will tell you that you should spend $12 a quart because it says V-Twin on the label and why would you want to use cheap oil on your $25,000 Harley.
Road Warrior
Joined: Oct 2007
Posts: 1,468
Likes: 4
From: South Carolina
Booooyah! if the dealership says you have to use it, then they have to change it for free.
So let’s be clear – Federal Law – under the Magnuson-Moss Warranty Act (1975) Title 15, Chapter 50, Section 2301-3312, US Federal Code, — a vehicle manufacturer or its authorized dealerships may not make a vehicle warranty conditional upon the use of its service (alone), or the use of any brand of product, unless that manufacturer provides the product or service free of charge or that the Federal Trade Commission has specifically stated and published that the vehicle manufacturer’s product or service is the only product or service available to comply to satisfy relief of warranty claims.
So let’s be clear – Federal Law – under the Magnuson-Moss Warranty Act (1975) Title 15, Chapter 50, Section 2301-3312, US Federal Code, — a vehicle manufacturer or its authorized dealerships may not make a vehicle warranty conditional upon the use of its service (alone), or the use of any brand of product, unless that manufacturer provides the product or service free of charge or that the Federal Trade Commission has specifically stated and published that the vehicle manufacturer’s product or service is the only product or service available to comply to satisfy relief of warranty claims.
Grand HDF Member
Joined: Nov 2012
Posts: 3,751
Likes: 459
From: Here and now
As I stated a few posts ago, I use the 15/50 synthetic Mobil 1 and it's fine. The special motorcycle formula that so many people use is really for bikes that have "one hole" for all fluids because it is designed to work with the clutch too. Because our crank and clutch are separate, we don't need to worry about it. Of course many on this board will tell you that you should spend $12 a quart because it says V-Twin on the label and why would you want to use cheap oil on your $25,000 Harley.
Ultimate HDF Member
Joined: Jan 2008
Posts: 6,532
Likes: 132
From: SoCal
I wouldn't run the syn 3 in the primary, I'd run either Formula+ or another non-syn primary fluid(rev-tec, drag, v-twin, whatever) because it is cheaper and a bit better suited for the primary area. I also wouldn't use a motor oil in a trans, I would use Formula+ or another Trans specific fluid, non-syn or syn , doesn't really matter. Whatever the oil company packages as a V-Twin trans fluid will be fine.
Last edited by qtrracer; Mar 26, 2014 at 01:29 PM.
Ultimate HDF Member
Joined: Jan 2011
Posts: 9,850
Likes: 220
From: Sacramento, CA.
I ran Syn 3 in my 07 FLHT STD. in all three holes. When I bought my 2011 FLTRX, no way was I going to run it. Ran HD dino until 5k & used Red Line 20/50 in engine, Red Line Shock Proof in trans & HD Formula+ in primary. Syn 3 is to light to be in your Trans.
Road Master
Joined: Oct 2013
Posts: 1,168
Likes: 114
From: Drummondville, Qc, Canada
I agree for the equivalence, but an engine oil does not have the same package of additives than a real gearbox oil.
I use an engine oil in my engine and a gearbox oil in my gears... but like a lot of peoples said... it's a personnal choice
I use an engine oil in my engine and a gearbox oil in my gears... but like a lot of peoples said... it's a personnal choice
Cruiser
Joined: Aug 2013
Posts: 173
Likes: 12
From: South Hadley MA
As I stated a few posts ago, I use the 15/50 synthetic Mobil 1 and it's fine. The special motorcycle formula that so many people use is really for bikes that have "one hole" for all fluids because it is designed to work with the clutch too. Because our crank and clutch are separate, we don't need to worry about it. Of course many on this board will tell you that you should spend $12 a quart because it says V-Twin on the label and why would you want to use cheap oil on your $25,000 Harley.
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Ultimate HDF Member
Joined: Jul 2006
Posts: 7,705
Likes: 358
From: C-Town
I, for one, am happy to see an oil thread! Much better than 5 "snow/cold" threads every F-ing day!
Tourer
Joined: Dec 2009
Posts: 338
Likes: 2
From: North Central CT
I know there are 15000 oil threads, but I still read them as I've not quite figured out what my favorite mix is because my bike is barely broken in at a few miles short of 20k. All I know was that at the 1k service, they switched to Syn 3....I took off after the service and immediately pulled over because I thought something was wrong. Bike felt totally different with Syn 3 in all three holes. I hated it. I've been tinkering since, but I've decided I won't put synthetic in my transmission.