Well after 3 days of research, I just pulled the trigger and ordered some 20W-50 for the Primary and Crank, and Severe Gear 75W-90 for the tranny. Still not sure about the 75W-90 for the tranny. Am I doing the right thing? Please tell me I am doing the right thing. Right now Sally (My '07 FLSTC) has syn3 in all 3 holes.

 

Your good to go ,I run the 20-50 crank and primary and the 75-110 in trans

 

I switched from Syn3 to Amsoil a couple of yesrs ago and will stick with it.
As I've said elsewhere, when I ran Syn 3 on 3,000 mile trips from home to Key West, I always had to top off a couple ounces before the return trip. With Amsoil There wasn't any burnoff at all.

 

You will be fine. Good choices IMO.

 

Not sure I'd spend the money to put amsoil in the primary. Of course, I wouldn't spend the money to put it in the crank or tranny, either.

 

You're good to go

 

Had occasion to open the cam case up to change from woods 7H to woods 400-6.
Had 12000 on the 7H, put in at 1000 miles 08 Fatboy.

Ran Amsoil 20-50

No wear in the crank pinion
No wear on the chain tensioners.
No wear on the cam support plate cam, "self" bearings.

Looked almost new.

 

Are you sure you don't need 60 oil? Check manual for your year.