75W-90 vs 75W-140
Road Master
Joined: Aug 2008
Posts: 898
Likes: 66
From: Slidell, Louisiana
Just replaced the tranny fluid at the 12000 mark. Went with Royal Purple 75/90. The HD fluid was rather dirty. A good bit of trace metal on the drain plug. Driving from FLA TO LA tomorrow, so I will let you know how it does.
Seasoned HDF Member
Joined: Mar 2009
Posts: 24,728
Likes: 9,235
From: Snow Hill, NC
75/90 in my opinion is sufficient, not a lot of heat going on in in there and syn gear oil can last quite a while, I think I change it at 20000 but it may have been at 10k this year, I useD 75/90 Amsoil Severe gear thus time because I got it girl like $8 a quart on sale. In all the different trans oil I have used I have really never felt much difference. Just make sure you change it.
Road Master
Joined: Sep 2012
Posts: 876
Likes: 4
From: Waskom, TX
David
Club Member
Joined: Dec 2007
Posts: 4,192
Likes: 168
From: Knoxville, Tn
Gear Oil
I have been running Spectro 75w140 for about 8 years now and haven't had any problems what-so-ever.
I have noticed that finding neutral on my touring bike is harder when the engine is really hot. When the engine is cooler, it will pop into neutral with no problem at all. The 103s tend to run hotter than anything I have ever ridden.
I took the moveable doors off the lowers because of the heat and the fact that they sometimes vibrate to something other than wide open in the summer. I took the doors off about a week ago.
I took a long ride yesterday, a little over 200 miles, and noticed a change in the air flow pattern over the engine...It was better. The only time the engine got hot was when climbing steep hills at low speed and high torque situations.
I have noticed that finding neutral on my touring bike is harder when the engine is really hot. When the engine is cooler, it will pop into neutral with no problem at all. The 103s tend to run hotter than anything I have ever ridden.
I took the moveable doors off the lowers because of the heat and the fact that they sometimes vibrate to something other than wide open in the summer. I took the doors off about a week ago.
I took a long ride yesterday, a little over 200 miles, and noticed a change in the air flow pattern over the engine...It was better. The only time the engine got hot was when climbing steep hills at low speed and high torque situations.
Tourer
Joined: Jul 2014
Posts: 473
Likes: 5
From: New Braunfels TX
Amsoil 75/140 is what I use, always have since I got the bike and this is my first Harley, this is what the Dealership uses in their bikes and recommends and sells so I use it.
Last edited by Highwayman-AL; May 15, 2015 at 09:30 AM.
Road Master
Joined: May 2008
Posts: 1,178
Likes: 5
From: Central Calif
I have used amsoil 20-50 in my trans for 104,000 miles -- changed it once around 75,000 and it looked exactly like when I put it in. no filings on magnet -- shifts fine for me --
a lot of friends have tried different oils/gear oil -- with mixed results
a lot of friends have tried different oils/gear oil -- with mixed results
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Ultimate HDF Member
Joined: Feb 2012
Posts: 7,855
Likes: 11
From: Oroville,Washington.
Redline (NOT Shockproof) 90/140 for the last 35,000 miles. Comes out as clean as it went in. Lots of mountain running up here,curves and constant downshifting,so I err on the heavy side.
