Board index Flathead Power-Technical Questions, Answers, and Suggestions Twin Cams Substitute Lube.....

Substitute Lube.....

Post Wed Mar 14, 2007 3:37 pm

Posts: 5
Location: Louisiana
What is a good Auto Parts store substitute for H-D primary case lube?

Post Sat Mar 31, 2007 10:59 pm

Posts: 1538
twinkeez run the same oil in all 3 areas, motor/tranny/primary.

since oil is the cheapest thing on a HD, i don't scrimp on it..

Post Wed Aug 12, 2009 1:14 pm

Posts: 24
Location: My-am-mah, Flor-a-duh
I use AMSOIL SAE 20W-50 Synthetic Motorcycle Oil (MCV):

It may cost a little bit more but I think it is worth it. Living in south FLA things get pretty hot. Although I don't have any numbers to back it up, I think my RK runs a bit cooler with the AMSOIL syn. In standard ASTM testing AMSOIL performs better than the HD syn3 and HD 360 (and just about everything else): ... Paper.aspx

1946 knucklehead
1976 shovelhead
2006 road king

Youth and enthusiasm is no match for age and treachery.

Post Fri Mar 25, 2016 2:19 am

Posts: 1
I use Mobil One for V-Twins 20w-50 in the crankcase. Competitively priced, many have been using Mobil One for years with good results. You can get it in just about any auto parts store or WalMart, so it's convenient to get in a pinch. I'd be inclined to change my crankcase oil more often that the factory specifies. It's cheap insurance on the most expensive part of the bike.
Red Line Transmission Oil and Red Line Primary Oil in the other two holes.

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