The MoCo recommend Formula + oil in 6-sp Cruise Drive

[xlfan]

Does anyone know the reason to NOT use H-D Semi-Synth transmission oil, or any other transmission oil in the 6-speed Cruise Drive transmission?

What could be the negative effect of a clingy transmission fluid, in a mechanical contraption like a transmission, without the lubricating help from an oil pump?

[smoserx1]

I'm not sure I understand the question, especially the second part, but the semi-synthetic oil should work fine, as well as the formula +.  AFAIK the only oils you should not use in manual transmissions are very high sulfur oils in transmission containing yellow metal (brass synchronizes), which motorcycle transmissions do not use.  I am using Valvoline, which I picked up at a buy one get one sale, but must of my transmission's life has seen formula +, which I absolutely love.

[xlfan]

The factory were very specific when they warned against use of H-D semi-synth tramission oil in the then, new 6-Speed Cruise Drive transmission in 2006.

I just wondered if anyone knew the reason for this, if there was any.

[kouack]

The factory were very specific when they warned against use of H-D semi-synth transmission  oil in the then, new 6-Speed Cruise Drive transmission in 2006.

I just wondered if anyone knew the reason for this, if there was any.

Maybe... because they were not selling any at the time now they sell synthetic tranny oil and one size fit all! You have to be careful with the word "semi-synthetic " oil go read the meaning of it basically anything with 5% to 95% mixed of dino/synthetic blend will be called "semi-synthetic" lol for what it worth.

[rbabos]

The factory were very specific when they warned against use of H-D semi-synth tramission oil in the then, new 6-Speed Cruise Drive transmission in 2006.

I just wondered if anyone knew the reason for this, if there was any.

Lube not up to the task and more then normal failures. Why the hell anyone would want to use Syn3 in a gear box or primary is beyond me.
Ron

[dirty jim]

The factory were very specific when they warned against use of H-D semi-synth tramission oil in the then, new 6-Speed Cruise Drive transmission in 2006.

I just wondered if anyone knew the reason for this, if there was any.

Lube not up to the task and more then normal failures. Why the hell anyone would want to use Syn3 in a gear box or primary is beyond me.
Ron

Because they have a V-rod?

(sorry, couldn't resist)

[MikeL]

At least 10 yrs ago my local dealer put all their semi-synthetic gear oil on the bargain table @ $1.95 a quart. I bought it all. I still have some and still use it. Engine oil rated at GL2 @ $10.00+per qt when I can install a GL-4 transmission specific oil @ $1.95 per qt. When I run out then it's back to the red mucus oil.

                                                                                                                                                                  MIKE

[tomcat64]

The factory were very specific when they warned against use of H-D semi-synth tramission oil in the then, new 6-Speed Cruise Drive transmission in 2006.

I just wondered if anyone knew the reason for this, if there was any.

Lube not up to the task and more then normal failures. Why the hell anyone would want to use Syn3 in a gear box or primary is beyond me.
Ron

I've  never understood the Syn 3 in all three holes either, but it must work, our customers have been doing it for years and we have never seen a problem, 100K+ miles and more..

[hattitude]

The factory were very specific when they warned against use of H-D semi-synth transmission  oil in the then, new 6-Speed Cruise Drive transmission in 2006.

I just wondered if anyone knew the reason for this, if there was any.

Maybe... because they were not selling any at the time now they sell synthetic tranny oil and one size fit all! You have to be careful with the word "semi-synthetic " oil go read the meaning of it basically anything with 5% to 95% mixed of dino/synthetic blend will be called "semi-synthetic" lol for what it worth.

I remember being warned by a dealer that I used many years ago, against using "any synthetic oil in a Harley... period..."

Then HD came out with the Syn3 oil. The same dealer was then recommending Syn3 in all three holes of the same bike they warned me never to use "any synthetic oil in... period..."

All too often, the MoCo's recommendations are more marketing than what's best for the bike... all they care about is that it makes it through its warranty in one piece....

[CndUltra88]

Does anyone know the reason to NOT use H-D Semi-Synth transmission oil, or any other transmission oil in the 6-speed Cruise Drive transmission?

What could be the negative effect of a clingy transmission fluid, in a mechanical contraption like a transmission, without the lubricating help from an oil pump?

What does Earl have o say about this question?
Anyone, anyone...
Rob

[smoserx1]

The factory were very specific when they warned against use of H-D semi-synth tramission oil in the then, new 6-Speed Cruise Drive transmission in 2006.

I just wondered if anyone knew the reason for this, if there was any.

Actually I don't recall any H-D semi-synthetic transmission oil.  They used to have a separate big twin transmission oil and primary lube and a combined oil for sportsters, both of which I believe was replaced with Formula +.  Also there was Syn 3,  and finally now a new 80-140 heavy synthetic transmission oil.  Looking at the latest catalog info about Syn-3 it does not seem to say not to use it in a H-D 6 speed.  But anyway, consider this:
1.  I have a truck right now that uses ATF in a manual transmission.
2.  I have owned a car  that specified 10-30 or 10-40 car oil in a manual transmission.
3.  Many motorcycles by design must lubricate their transmissions (and primaries) with engine oil because they have only one "hole."
Motorcycle transmissions are not synchronized so they bang when they shift (and this drives some folks crazy).  A lightweight oil will make the transmission noisy and may accelerate the wear on the dogs of the gears.  A heavy oil like a differential oil  will quiet it down some and maybe prolong the life of the dogs, but if you store and ride the bike in cold weather if will likely be hard to shift, especially when cold.  Other than that you can probably run  just about anything in it.  I  don't see how it is going to damage it, especially if you change the lubricant regularly.

[motorhogman]

The factory were very specific when they warned against use of H-D semi-synth tramission oil in the then, new 6-Speed Cruise Drive transmission in 2006.

I just wondered if anyone knew the reason for this, if there was any.

Actually I don't recall any H-D semi-synthetic transmission oil.  They used to have a separate big twin transmission oil and primary lube and a combined oil for sportsters, both of which I believe was replaced with Formula +.  Also there was Syn 3,  and finally now a new 80-140 heavy synthetic transmission oil.  Looking at the latest catalog info about Syn-3 it does not seem to say not to use it in a H-D 6 speed.  But anyway, consider this:
1.  I have a truck right now that uses ATF in a manual transmission.
2.  I have owned a car  that specified 10-30 or 10-40 car oil in a manual transmission.
3.  Many motorcycles by design must lubricate their transmissions (and primaries) with engine oil because they have only one "hole."
Motorcycle transmissions are not synchronized so they bang when they shift (and this drives some folks crazy).  A lightweight oil will make the transmission noisy and may accelerate the wear on the dogs of the gears.  A heavy oil like a differential oil  will quiet it down some and maybe prolong the life of the dogs, but if you store and ride the bike in cold weather if will likely be hard to shift, especially when cold.  Other than that you can probably run  just about anything in it.  I  don't see how it is going to damage it, especially if you change the lubricant regularly.

just happen to have a quart of that semi syn trans oil  No weight listed, just multi viscosity.

[smoserx1]

 
I certainly missed that one.  I see copyright 1995 on the back...old stuff for sure!

[motorhogman]

I certainly missed that one.  I see copyright 1995 on the back...old stuff for sure!

Yea...old is right.. I've had that kicking around for at least 20 years..