I sell Amsoil. Put Amsoil Signature Series oil, transmission, and differential fluid in it the day you buy it. It's 100% synthetic.....the best cooling properties of any fluid on the market, and it maintains its viscosity at high temperatures. It's warranty secure also.That extra fluid and cooling capacity would be a big benefit to hard off roading or long cruises on southern interstates. I wonder if there would be any impact to factory warrantee?