Tranny Fluid Preferences
Seasoned HDF Member
Joined: Mar 2014
Posts: 15,365
Likes: 24,241
From: NC, USA
I just switched over to the Spectro ^^^ on the advice of my Indy guy who's been in biz since 1974. It's in my Street Glide and the shifts are smoother and quieter, less clunking. Most likely this will go in my SS when it's do for a change.
Road Captain
Joined: Sep 2013
Posts: 575
Likes: 190
From: USA
Tried Redline Shock Proof Lightweight and noticed a funny whining/load/squeal when down shifting or letting off the throttle. Noticed it immediately after changing fluid. Wasn't sure if it was related to the trans. Put about 15-20 miles on the bike and decided to cut my loss and change the fluid since this seemed like the logical solution. I went to the local auto parts store and picked up some Mobile1 75-90, so drain and refill again. After I started the bike up and rode down the block I could still hear the noise but after about 1 mile it was gone and all is well. It's been 80 miles since the change and I'm happy with an oil that is working for me. Not sure what the previous owner was using but it looked like it was ready for a change.
Seasoned HDF Member
Joined: Jun 2010
Posts: 9,332
Likes: 3,873
From: Upstate New York
I used H-D semi-synthetic transmission lube until the MoCo replaced it with "Formula +". IMO, gearboxes should be lubricated with gear oil, not some "one size fits all" product. Since 2010, I've used Valvoline 85W-140 gear oil, since it's inexpensive and available locally.
187,000 miles on my transmission and it's never been apart. I change the oil at every 5K service.
187,000 miles on my transmission and it's never been apart. I change the oil at every 5K service.
Club Member
Joined: Feb 2007
Posts: 2,404
Likes: 12
From: Haymarket, VA
I tried Spectro Platinum at first tranny oil change to hopefuly lessen the 5th gear whine. It did help a little bit, decided to try Mobil-1 75W-140 at about 15K for one change, no difference. I've not tried Redline yet, but I would'nt expect any difference either, I've gotten use to the whine, & it shifts easy with the Spectro.
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Road Master
Joined: Jun 2012
Posts: 1,119
Likes: 7
From: USA
I think any quality tranny lube is going to get the job done. The real difference between the difference lubes won't be seen on a day to day basis. But the difference will only be seen in long term wear to the tranny components. My feeling is if you run your bike in hot a cold conditions, then a good synthetic 75W-140 lube is all you need.