Rotella T ????
Outstanding HDF Member
Joined: Sep 2010
Posts: 2,630
Likes: 185
From: Mountain West, Big Sky Country
After reading about 30 or more answers, my head is spinning with all the info put out...which is a good thing if you can keep up...I can't.
Someone please answer this (somewhat simple) question. I just bought a 2010 Ultra from a friend and he had used synthetic since new. It now has 27,000 + and I am going to change everything myself. (crankcase, primary and trans). What would the best synthetic be for all 3? I'll only say that the bike does not shift well (clunks) into every gear. I know that may come from clutch adjustment though. Thanks
Someone please answer this (somewhat simple) question. I just bought a 2010 Ultra from a friend and he had used synthetic since new. It now has 27,000 + and I am going to change everything myself. (crankcase, primary and trans). What would the best synthetic be for all 3? I'll only say that the bike does not shift well (clunks) into every gear. I know that may come from clutch adjustment though. Thanks
Any company 75/140 synthetic gear lube,
10w40 motor oil in primary (any brand, cheaper the better)
You'll be fine
Extreme HDF Member
Joined: Jun 2011
Posts: 10,216
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From: Glendale AZ
The Shell Rotella T6 not T5 or just Rotella is a syn oil spec'd for wet clutches. When you talk about Rotella you must identify the specific version. All squares are rectangles not all rectangles are squares.
I use it in all my bikes now from a Street 750 to a 120R. Walmart has it in 4 qt. containers for under $20. If it did not work with a HD wet clutch it would show up in a clutch being challenged with a 120R. All Shell employees that have HD's use T6. I have talked to many at various semi truck shows over the years where Shell brings in a display and reps. Of course they get it cheap.
Good enough for 600HP diesel engines good enough for a Briggs and Stratton Harley Davidson.
I use it in all my bikes now from a Street 750 to a 120R. Walmart has it in 4 qt. containers for under $20. If it did not work with a HD wet clutch it would show up in a clutch being challenged with a 120R. All Shell employees that have HD's use T6. I have talked to many at various semi truck shows over the years where Shell brings in a display and reps. Of course they get it cheap.
Good enough for 600HP diesel engines good enough for a Briggs and Stratton Harley Davidson.
Seasoned HDF Member
Joined: Feb 2016
Posts: 8,001
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From: NC
So, no one is running O'Reilly's 30 weight oil in their primaries? What's so different about twin cam primaries from the earlier EVOs? It's only splash lubrication for the chain and clutch.
Grand HDF Member
Joined: Aug 2014
Posts: 4,725
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From: Toledo ohio
I use Rotella 15/40 Diesel oil in my primary and also use it in T-5 transmissions like in mustangs and S-10's. I worked at Jasper Engines for quite a while (no throwing wrenches) and when we started rebuilding these, the 5th gear headset would burn up on a lot of them. We determined that due to the factory recommended oil, ATF, if you are pulling a heavy load in 5th gear, whether it is a trailer, or ton of bricks in the bed, or foot in the pedal, it would, by how the gear train is designed, put excessive heat on the rear gear set (actually outside the case in the extension housing) and burn up 5th gear. By testing, we found 15/40 diesel engine oil, such at Rotella, would prevent overheating of the head set. Take that for what it is worth.
Seasoned HDF Member
Joined: Sep 2008
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From: San Diego, CA
It says Super right on the label!!!!!
Extreme HDF Member
Joined: Jun 2011
Posts: 14,731
Likes: 2,536
From: Mountain Top, Alabama
I use Rotella 15/40 Diesel oil in my primary and also use it in T-5 transmissions like in mustangs and S-10's. I worked at Jasper Engines for quite a while (no throwing wrenches) and when we started rebuilding these, the 5th gear headset would burn up on a lot of them. We determined that due to the factory recommended oil, ATF, if you are pulling a heavy load in 5th gear, whether it is a trailer, or ton of bricks in the bed, or foot in the pedal, it would, by how the gear train is designed, put excessive heat on the rear gear set (actually outside the case in the extension housing) and burn up 5th gear. By testing, we found 15/40 diesel engine oil, such at Rotella, would prevent overheating of the head set. Take that for what it is worth.
Lots of options for lubes in the primary, another key is to keep it changed. I change all 3 holes at no more than 5 K miles, I can't see why anyone would go 10 K or more in any one of them.
Road Captain
Joined: Jul 2014
Posts: 717
Likes: 15
From: San Dimas
I agree with the "change it in a timely fashion" is probably more important than name-brand or slight variances in oil weight.
Personally, Rotella T 5, 6, and 7 all live in my bikes, and I am not afraid to buy Mobile 1 when I need to .... lol.
Personally, Rotella T 5, 6, and 7 all live in my bikes, and I am not afraid to buy Mobile 1 when I need to .... lol.
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Extreme HDF Member
Joined: Jun 2011
Posts: 10,216
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From: Glendale AZ
I knew a man that built manual transmissions many years. He agreed with the above that the ATF did not cut it in the 5 speeds, He said run 10w40 oil in the trans in place of the factory ATF and all will remain well. This was proven over and over again. He would boldly mark this on the side of the trans case.
Lots of options for lubes in the primary, another key is to keep it changed. I change all 3 holes at no more than 5 K miles, I can't see why anyone would go 10 K or more in any one of them.
Lots of options for lubes in the primary, another key is to keep it changed. I change all 3 holes at no more than 5 K miles, I can't see why anyone would go 10 K or more in any one of them.
Extreme HDF Member
Joined: Jun 2011
Posts: 14,731
Likes: 2,536
From: Mountain Top, Alabama
Point taken. And of the 3 holes, it's usually the nastiest one of them all at drain time.