Harley Davidson Forums

Softail Models Standard, Custom, Night Train, Deuce, Springer, Heritage, Fatboy, Deluxe, Rocker and Cross Bones.
Sponsored by:
Sponsored by:

Oil viscosity

Thread Tools
 
Search this Thread
 
Old May 28, 2018 | 08:40 AM
Share
  #1  
dakers38's Avatar
dakers38
Thread Starter
|
Stage II
Joined: May 2018
Posts: 2
Likes: 0
From: virginia
Default Oil viscosity
what is the viscosity for the clutch oil and chain oil in a Harley softail heritage classic. I know the quanties but can't find a reference for viscosit
 
Reply
0
Old May 28, 2018 | 11:49 AM
Share
  #2  
mplazz's Avatar
mplazz
Advanced
Joined: Aug 2014
Posts: 63
Likes: 15
From: St. Petersburg, FL
Default
You don't mention what year. For 2003 Softail, the manual states using 20w-50 (preferred), 15w-40 or 10w-40 in the crank case. It does not state the viscosities of the oils for the Primary or Transmission, only the HD part number. Some Harley dealers put the same oil in all 3 holes.
 
Reply
0
Old May 28, 2018 | 12:17 PM
Share
  #3  
Flstcjay's Avatar
Flstcjay
Tourer
Joined: Apr 2018
Posts: 280
Likes: 103
From: Manitoba
Default
 
Reply
0
Old May 28, 2018 | 12:32 PM
Share
  #4  
langwilliams's Avatar
langwilliams
Elite HDF Member
15 Year Member
Photogenic
Liked
Loved
Joined: Jul 2010
Posts: 3,830
Likes: 302
From: Lorain Ohio
Default
I just put rotella 15w40 in mine an it shifts well an clutch feels good.
 
Reply
0
Old May 28, 2018 | 01:54 PM
Share
  #5  
dakers38's Avatar
dakers38
Thread Starter
|
Stage II
Joined: May 2018
Posts: 2
Likes: 0
From: virginia
Default
Thanks, that's a help,and mine is 2001 Softail Heritage Classic
 
Reply
0
Old May 28, 2018 | 03:00 PM
Share
  #6  
blackxpress's Avatar
blackxpress
Road Master
Joined: Sep 2016
Posts: 1,048
Likes: 492
From: Heart of Georgia
Default
Your manual doesn’t say because it really isn’t all that critical. Just don’t put gear oil in there. It tends to be too heavy. Some guys use 20w50 motor oil and some guys use ATF fluid. Me? I prefer primary chaincase oil since that’s what it’s for. Right now I’m running HD Formula +, which is basically straight 50w oil. I’ve used Lucas and Bel Ray in the past and can’t really tell any difference between those and the Formula +. Some people say you should avoid oils with extra friction modifiers because they can cause clutch slippage. Personally I just figure if it says primary chain case on the bottle I’m good to go regardless of the actual viscosity.
 
Last edited by blackxpress; May 28, 2018 at 03:01 PM.
Reply
1
Old May 29, 2018 | 06:16 AM
Share
  #7  
heybaylor's Avatar
heybaylor
Stellar HDF Member
15 Year Member
Liked
Joined: Oct 2010
Posts: 2,594
Likes: 178
From: east texas
Default
Originally Posted by langwilliams
I just put rotella 15w40 in mine an it shifts well an clutch feels good.

Same here in all my bikes, 30 years and still running
 
Reply
0

Trending Topics

Old May 29, 2018 | 12:16 PM
Share
  #8  
Tom84FXST's Avatar
Tom84FXST
Seasoned HDF Member
15 Year Member
Liked
Loved
Community Favorite
Joined: Nov 2009
Posts: 15,705
Likes: 22,718
From: Farmington ,MS
Default
Originally Posted by blackxpress
Your manual doesn’t say because it really isn’t all that critical. Just don’t put gear oil in there. It tends to be too heavy.
Been running gear oil in mine for 10 years, with no problems...really not critical
 
Reply
0
HD Forum Stories

The Best of Harley-Davidson for Lifelong Riders

story-0

7 Surprising Harley-Davidson Products that Are Not Motorcycles

 Verdad Gallardo
story-1

8 Best Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-2

10 Worst Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-3

Killer Custom's Jail Break Is The Breakout That Refused to Blend In

 Verdad Gallardo
story-4

Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?

 Verdad Gallardo
story-5

Harley-Davidson Reveals Super Cool Cafe Racer Concept

 Verdad Gallardo
story-6

Engraved Rebellion: Inside Bundnerbike's Glam Rock II

 Verdad Gallardo
story-7

10 Motorcycles You Should Never Buy

 Joe Kucinski
story-8

10 Things Harley-Davidson Needs to Fix in 2026

 Verdad Gallardo
story-9

Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider

 Verdad Gallardo
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Trans oil Transfer: only hydraulic clutches?
Steve Sportster
Milwaukee Eight (M8)
5
Nov 7, 2018 08:03 AM
Oil Level Very Low in Primary, 99 FLSTC Heritage Classic
Kayakeur
EVO
20
Sep 10, 2015 07:24 AM
Primary oil tranny oil clutch oil
SportsterSnow
Sportster Models
3
Sep 8, 2014 05:06 PM
Prmary oil level
johnod
EVO
8
Jun 1, 2014 01:56 PM
primary oil level
aoehero
Oil Archive (no new posts)
1
Jun 16, 2011 09:44 PM
Back to Subforum
Softail Models
View Next Unread
2018 Softail seat swaps (LR, SG & FB)...anyone tried it?




Advanced Search
Reply Closed Thread Share
Forum Jump

All times are GMT -5. The time now is 01:27 AM.

story-0
7 Surprising Harley-Davidson Products that Are Not Motorcycles

Slideshow: The bar-and-shield logo shows up on far more than motorcycles, some of the company's most unexpected products have nothing to do with riding.

By Verdad Gallardo | 2026-04-29 16:50:35


VIEW MORE
story-1
8 Best Harley-Davidson Motorcycles Ever

Slideshow: Not every Harley gets it right, but these are the ones that genuinely earned their reputation.

By Pouria Savadkouei | 2026-04-15 14:23:21


VIEW MORE
story-2
10 Worst Harley-Davidson Motorcycles Ever

Slideshow: From the troubled AMF years to modern misfires, these bikes earned reputations for reliability issues, questionable engineering, or disappointing performance.

By Pouria Savadkouei | 2026-04-01 20:01:09


VIEW MORE
story-3
Killer Custom's Jail Break Is The Breakout That Refused to Blend In

Slideshow: Killer Custom's "Jail Breaker" build focuses more on stance and visual aggression than mechanical overhaul.

By Verdad Gallardo | 2026-03-18 19:20:32


VIEW MORE
story-4
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?

Slideshow: The Swiss custom shop has taken a Harley Softail and stretched it into something so long and low that it looks closer to a rolling sculpture than a conventional motorcycle.

By Verdad Gallardo | 2026-03-07 16:15:30


VIEW MORE
story-5
Harley-Davidson Reveals Super Cool Cafe Racer Concept

Slideshow: Harley-Davidson's new RMCR concept revives the café racer formula with modern hardware-and it may be exactly the reset the company needs.

By Verdad Gallardo | 2026-03-04 12:23:37


VIEW MORE
story-6
Engraved Rebellion: Inside Bundnerbike's Glam Rock II

Slideshow: A standard cruiser becomes an intricate metal canvas in the hands of a Swiss custom house known for pushing Harley-Davidson platforms far beyond their factory brief.

By Verdad Gallardo | 2026-02-24 18:19:44


VIEW MORE
story-7
10 Motorcycles You Should Never Buy

Slideshow: There is no shortage of great motorcycles to buy, but we would avoid these ten.

By Joe Kucinski | 2026-02-19 14:50:51


VIEW MORE
story-8
10 Things Harley-Davidson Needs to Fix in 2026

Slideshow: Harley-Davidson's challenges aren't abstract; they show up in dropping shipments, shrinking dealer traffic, and strategic decisions that aren't yet translating into growth.

By Verdad Gallardo | 2026-01-13 18:33:17


VIEW MORE
story-9
Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider

Slideshow: Graeme Billington's left-hand-drive Shovelhead is as much about problem-solving as it is about classic Harley form.

By Verdad Gallardo | 2025-12-30 11:27:08


VIEW MORE