Engine oil Kendall or AMSOIL

Based on my own tests, I found the AmsOil to be the best at reducing heat a few degrees. It's not cheap, but it's still cheap insurance, all things considered.

I use Amsoil 20w50 in all 3. You don’t need a different oil for the trans. Amsoil is not cheap but I’ve been using it on my 03 FatBoy since new and have had no problems.

Originally switched to Amsoil for the Noack rating but stayed because it's just good stuff. I now run Amsoil products for all fluids in all vehicles.

I use AMSOIL 5W-30 for both of our vehicles. Never had any issues on either vehicle using AMSOIL.

Amsoil Signature 5w-20 + K&N Gold oil filter (HP1017 for 4th gens, not sure about 5th) is arguably the single best combo if you can afford the oil. Your lobes will thank you.

The first thing I did was change the oil using a wix filter and Amsoil signature series 5w30. The verdict is that the oil has plenty of life left and could have easily run longer.

Amsoil W20 I got a 5.7 it’s been great to me

Amsoil Signature Series 0w40 is an outstanding oil I run it with the SRT filter.

Ran Kendall 15x40 for a number of years, ran Shell T4 till it got oddly hard to find, currently running Delo 15w40

im actually running that oil right now... I hate it tbh. 3,100 on the oil and it has allowed excess engine noise since day one, SUPER harsh cold starts, and now its burning through faster than the catrol I ran when I first got the car. a WHOLE QUART over 750 miles. the oil is thinner than piss going in, and it just doesnt stand up to what my engine can put out like Shell Rotella T6 has been doing...