What the opinion on Amsoil HD 5W40? Local hardware sells it by the gallon at an attractive price.
https://www.amsoil.com/shop/by-prod...ynthetic-diesel-oil-5w-40/?code=ADOQT-EA
https://www.amsoil.com/shop/by-prod...ynthetic-diesel-oil-5w-40/?code=ADOQT-EA