Tranny oil recomendations
Cruiser
Joined: Mar 2008
Posts: 210
Likes: 1
From: West Chester, PA
Amsoil 75W-110, Belray Transmission or 85W-140, Spectro Platinum 75W-140 Transmission or Redline Shockproof Heavy are some of the best choices on the market for your transmission. 20W-50 motor oil will work, but it's not the "best" fluid for the application.
Ultimate HDF Member
Joined: Nov 2008
Posts: 6,682
Likes: 12
With my 09 and the notorious 5th gear whine, I have found the Amsoil Severe Gear 75-110 keeps it quiet and shifting smoothly.
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Club Member
Joined: Jun 2008
Posts: 17,717
Likes: 1
From: NY
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Road Master
Joined: Jun 2007
Posts: 764
Likes: 42
From: Pensacola, FL
I was using Syn 3 in all three holes since 500 mile service, but was never really happy. So for the 15K service I put in Mobil 1 V-Twin 20-50 and Mobil 75-90 in the tranny and didn't notice a big difference. So, I just had the 20K service done and I put Syn 3 back in the engine and HD Formula + in the primary and tranny.
I'm now will always use HD Formula + in the primary and tranny. I really noticed a difference. Not sure what I'll use in the engine next.
I'm now will always use HD Formula + in the primary and tranny. I really noticed a difference. Not sure what I'll use in the engine next.
