Oil On All Three

I read in the Amsoil website that for HD we could use 20w-50 in all three. Mainly the Tranny, primary, and engine. HD recommends 75w-90 on the tranny. I am planning to apply it on my bike. What do you think guys of one in all three? Will void warranty? Will it overheat/foamy? Just wanted to know cause i ordered a case..Thanks in advance.

I don’t know what 20-50 would do in the tranny as far as foam or over heating but I always like to put gear lube in the gear hole. Some clam it shifts smoother with 75-90 or 80-90 in it too.

oil in all 3

Harley says their Syn 3 is ok to put it in the 3 holes, hence the name. Amsoil has said this for a long time. Engine oil and gear oil viscosities are rated differently so 20-50 is not much different from 75-90.

I thought that H-D now has separate tranny juice again?

We use Red Line and they have specific recommendations for each hole.

Chuck, I've been using Valvolene Syn 85W140 in my bikes for years. The Last bike I sold was a 1996 Road King with near 65k on it. Tranny was quite, shifted well, and none of the 4th gear "rocks in the tranny" feel the older trannys always had. The only drawback was if it was really cold out, it shifted a little stiff until a few miles had gone by to warm it. The syn 85W140 actually looked as thin or thinner than the 80W90 I was using prior to the switch. Big difference on a hot day though, tranny stays quiet and shifts right throughout.

Mobil One 15w50 in oil and primary, 75w90 in tranny. All synthetic and costs a hell of lot less for the same benefits (if not better than others).

Just to clarify, I was only speaking of the 85W140 in the tranny. Still just using the 20W50 in the engine, or 50W straight in the summer. Old worn engines, even 60W straight in the summer. Up in Indiana, never seen anyone use 70W straight, even in the summer months, in anything. Warm up would take awhile I would think......

The old AMV AMSOIL synthetic 20W50 motorcycle oil has worked well in all three. However some people noticed the shifting was better when they used AMSOIL 75w90 Severe Gear Lube. However, AMSOIL now has their new MCV (picture of Harley engine on front) and riders report this works better in the tranny than the Severe Gear Lube did. So I think this is now the way to go. One oil for all three, better shifting and double the factory recommended oil change or once a year, whichever comes first, to comply with the AMSOIL parts/labor warranty.