AMSOIL Signature series motor oils provides 90% better protection over other motor oils and has 50% more additives to fight sludge build up. Engine sludge forms and can wreak havoc on engines… this article tells how to prevent it! This article will show the effects of sludge-how synthetic oil and additives prevent sludge. And how severe service on an engine invites sludge build up. AMSOIL beats the competition in all tests for fighting sludge!