Castrol GTX Full Synthetic provides maximum protection to help fight the impact of severe conditions that can potentially shorten engine life. Tough driving conditions like idling on congested highways and frequent, short trips put peak loads on critical engine parts and create engine wear. Environmental factors like heat can lead to sludge, varnish and carbon build-up in your engine. Castrol GTX Full Synthetic has been proven to dramatically reduce engine wear - 6X better than the industry standard.** It also cleans away old sludge*** and protects against new sludge formation 1.3X better than required by the latest industry standard,* giving you more control over today's difficult driving conditions and miles more driving enjoyment.