Ok... Recently purchased an 04 FLHTC. It has stage 2, V&H true duals, and an Ultima 6 speed transmission. The previous owner was running Amsoil 20w/ 50 full synthetic in crankcase, tranny, and primary. 4th and 6th gear whine. I'm looking for suggestions on what oils to run. I'm not a motorcycle mechanic by any means, but to me it just doesn't seem right to run the same fluid for all the components. Suggestions please....!