Ya know...it's real easy to make fun of the idea of putting engine oil into a primary, but I don't think any of you are lubricant experts. There are lots of things out there that take on new/more uses. For example, a majority of 5 SPD MANUAL transmissions in the 80's used ATF. Who thought THAT made sense!?

 

Been using syn 3 HD oil in the primary and trans since new in my 08 RG. With 61k miles not a hint of a problem. No problems with wheel bearings either; still running the originals. Very entertaining thread though......

 

It would seem that a lube designed for high temps, clutch packs, gears and chains (automotive automatic trans components), requiring virtually no change interval in service, would work in a primary. Works in mine, the clutch is just fine, and not as sticky in the morning, particularly cold mornings.

 

That's been my experience too. Formula+ seemed to work equally as well on the sticky clutch plates though, just more $$.

 

and here we have it folks. use the hd syn3 engine oil and your wheel bearings will last longer

 

Yes, I've tried just about all oils in the primary including ATF and nothing is as good as Formula+ for me. I don't use Harley oil in the tranny or crankcase, so it's not that I'm a fan of the Harley brand, Formula+ just has the best feel with the clutch for me.

Beary

 

Been using AMSOIL ATF in my '80 FXEF primary for over a dozen years and AMSOIL synthetic ATF in my '03 FLHTCI primary for two years. HB 125 hydraulic chain tensioner in both, and both setups work very well. Smooth solid shifts under heavy loads, no clutch plate slippage, and clear fluid after 3k miles on the newer '03.

 

I agree DM

 

When I asked a couple of months ago (when I did my '11 Limited) they suggested HD +3 in primary and trans, I use Amsoil in the motor.

 

Interesting. I've never heard of using ATF in the primary but I guess that it's a good day if you can learn something new! I may try it sometime. Thank You.