Environmental factors such as poor petrol quality, hot weather and stop-start driving conditions can lead to sludge, varnish and carbon build-up in your engine: three factors that reduce engine life, power and petrol economy.
Castrol® Ultraclean is a synthetic blend engine oil available in 0W-20, 5W-20 and 5W-30 grades. Its double-action formula has been proven to clean away the sludge that can block engine oilways* and helps prevent new sludge formation thanks to its synthetic technology. In fact, it provides up to 1.4X better sludge protection than is demanded by the latest industry standard. If keeping your engine clean is important to you, it's good to know that no other oil keeps engines cleaner.CASTROL GTX ULTRACLEAN SAE 5W-20 synthetic blend is a unique double action formula that cleans away old sludge and protects against new sludge formation giving ou more control over today's environmental challenges .  Its double-action formula has been proven to clean away the sludge that can block engine oilways and helps prevent new sludge formation thanks to its synthetic technology.