I am preparing for my 1000 mile service and want to begin collecting the parts and fluids needed.

I read the proceedure in the service manual and it clearly states:

* Engine - 20/50 Full Synth

* Tranny - 20/50 Full Synth

* Primary - it just says Formula+ Transmission and Primary Chaincase Lubericant

I looked on the HD Website for Primary fluid and I didn't see anything. Are all 3 fluids the same?

Thanks

 

I used RL 20/50 engine, RP 75/140 trans, formula plus in primary. They are all different in my use

 

RP 75/140 trans?

Wow....the shop manual calls for 20/50. I don't know much but I would think 75/140 is a big difference then what the manufacturer is calling for.

So if I understand you correctly the Primary fluid is called Formula Plus.

Thanks....I was confused by what I was reading.

 

I have Mobil 1 v-twin 20w50 in all 3 holes.Same on last Limited for 30000 miles until traded.

 

20W50 all three holes .I use Amsoil. Just use what you want you will get all different answers

 

I like a primary fluid in the primary.

HD Formula+ is my choice.

But I run Amsoil 75W110 SevereGear in the tranny, and Amsoil 20w50 VTwin in the engine.

 

Very interesting replies....

 

As others have said, everyone has there combo. The formula + from hd it what I run in primary, and gear oil in trans and motor oil in motor. Lots of options for you, lots of opinions also. Biggest thing is to just change them regularly, whether using syn or not.

 

Agree 100% and thank you.

I just ordered Amsoil Trans SevereGear 75/110, Amsoil 20/50, and 2 filters. Renewed my 6 month trial for a $50 discount.

Will pick up Formula+ at the dealer and I should be set to roll for my 1000 mile service. I'll inspect all bolts for proper torque and adjust my belt if needed.

Thanks fellas.

 

Earlier question about weight of trans gear oil. Look up a viscosity chart you will find 90 weight gear oil is about the same viscosity as 50 weight engine oil but properties are different as trans gear oil has less heat but more shear between gears. I also run the heavier Mobil 1 gear oil that is a bit heavier than recommended because it seems to quiet the trans some and I figure its not being pushed through small oil holes by a pump so higher viscosity is not as critical. I started using synthetic oils in primary after the 1000 service but changed back to HD Formula+ at the 10,000 mile service and think the clutch engagement feels better with the Formula+.