Every dealer seems different. My local dealer recommended Schaeffer for both. 140-75 in trans and 30w in primary. Both syn. Primary seems a little light wt but haven't changed it yet. On 2017 road king. Seem to have lost abot 4 oz on trans but manual say that is normal?

 

What came out was a mixture of gear lube and water.

 

I just did the 1000 mile service on my 18 Road King. When I was at Harley's part counter buying a couple of quarts of formula plus the parts guy mentioned the new HD gear oil. He said it was kind of like the Redline Shockproof. He said it would take care of transmission whine. I don't have that so I passed on it. Looks like Harleys pushing this gear oil.

 

Of course they are, all companies push their products, it`s how you stay in business...

 

That's the first thing I checked for no water anyway how would water get into the trans.

 

I have been thinking about this I normally use formula plus in my other bikes but want to try this in my m8 stage 3. I found it online Utah HD for 16.50 a quart I figured if it's the same as redline then I will buy it incase something happens during the warranty I can show them the receipt and say hey you recommend it. Now for eng oil don't know what to do sn3,HD REGULAR or another brand.

 

Most likely through the vent tube.

 

I toyed with the idea of synthetic engine oil, and it does offer more protection and helps with heat with just about any syn you could find over dino.
Mobil one or Amsoil are good synthetics.
Mostly stick with one brand and stick with what weight HD says and you'll be fine.

 

I picked up a bottle of this gear oil today. I'm going to try it I'm my 2009 heritage.

 

Just put a quart in the primary and a little under a quart in the transmission. I’ll see how it performs on my trip up to Buffalo in a few days.