Primary Oil

[doc ock]

It amazes me that we can get hung up on primary oil. If you remember the ole shovelheads use motor oil coming from the same oil the feed the engine. Never had any problem then. Difference now the clutch plates can handle being wet.

[d1hojo]

I went to B&M trick shift in my primary and am very happy with it. Blue spot-promary, pnk spot-trans, oil spot-engine. oops, Mobile 1VT in motor, Redlin shock proof in trans. Very happy with this set up.

[Headshake]

You may think I'm crazy but I have found that John Deere Low Viscosity HyGard transmission oil works well in the primary. Deere has many, many, applications that run wet clutches and their HyGard is among the best oils for wet clutches.

[george douglas]

Originally Posted by Headshake

You may think I'm crazy but I have found that John Deere Low Viscosity HyGard transmission oil works well in the primary. Deere has many, many, applications that run wet clutches and their HyGard is among the best oils for wet clutches.

Tractor hydraulic oil is designed for wet brakes in many tractors that share the hydraulic system with the brakes and rear differentials and should work great in the primary. Just goes to show that there are many different products that will work in the primary.
george

[hdmarsh77]

JD fluid in the primary? I love it!

[Boo72]

Originally Posted by george douglas

Tractor hydraulic oil is designed for wet brakes in many tractors that share the hydraulic system with the brakes and rear differentials and should work great in the primary. Just goes to show that there are many different products that will work in the primary.
george

George -
With all this debate, what do you run in your primary? I had another AMSOIL dealer tell me to put 10w-40 MCF in the primary. Have haven't made any change yet, because I was going to put in ATF, but was told it was too thin. So now I'm not sure what I'm going to do.

[george douglas]

Originally Posted by Boo72

George -
With all this debate, what do you run in your primary? I had another AMSOIL dealer tell me to put 10w-40 MCF in the primary. Have haven't made any change yet, because I was going to put in ATF, but was told it was too thin. So now I'm not sure what I'm going to do.

Actually 10w 40 was the oil of choice about 5 years ago according to what harley was using in their primaries, but then they came out with their syn3 20w 50 and was using it in all three holes. I have used the 10w 40, the 20w 50, and last the supershift ATF fluid and that is what I like the best. You can't go wrong with any of them as long as the fluid meets wet clutch specs and we know that all automatic fluids meet wet clutch specs since wet clutches and gears is what is in the automatic trannies. The statement about viscosity being too thin has no consideration in this application.
george

[kerry_okie]

Originally Posted by d1hojo

I went to B&M trick shift in my primary and am very happy with it. Blue spot-promary, pnk spot-trans, oil spot-engine. oops, Mobile 1VT in motor, Redlin shock proof in trans. Very happy with this set up.

+1 on B&M. I found several quarts of the synthetic Trick Shift on closeout at an auto parts store so I'm set for life.

-- kerry --

[buddyrm]

Originally Posted by hotshotfxdl

Thats a great question you know I never payed any attention to it until I made the change to ATF. Man that baby gets pretty friggin hot !!!

Yup your right but think about how hot a automatic transmission gets while pulling a trailer/camper for thousands of miles without an oil cooler. :-) I think the temp in the Harley primary is no where near that. The ATF fluids are the ultimate in Ultra severe usuage. Think about it.

[george douglas]

Originally Posted by buddyrm

Yup your right but think about how hot a automatic transmission gets while pulling a trailer/camper for thousands of miles without an oil cooler. :-) I think the temp in the Harley primary is no where near that. The ATF fluids are the ultimate in Ultra severe usuage. Think about it.

Most of the heat is migrating from the engine in the primary, not the clutch and unless you take a temperature reading from the fluid itself you really can't tell by just touching the case. It most likely is well under 200 degrees. The optimum operating temperature for an automatic transmission is 180 degrees and if the temperature runs at a sustained higher temp of over 200 degrees then the fluid starts degrading.
george