when i just got my car...which is a 2001 proton putra 2 years back. i send it to my frens service center at shell and he did the engine flush for me. then after tat masuk the cheap shell mineral engine oil and bring the car out rev few rounds kau kau.....drain the mineral oil, then only fill in with the engine oil i want.
i still remember when drain the shell flushing oil tat time....zomg!! really brought the colour black to a whole new level.
i've been driving my car for 2 years now.....engine so far so good......regular service interval 4,000+ km with Eneos 10w40 semi-syn engine oil.
would recommend this Shell engine flush. but apparingly theres some pro's and con's though. for example if ur engine is in a really bad condition, this engine flush might do more harm than good. for example, remove sludge in ur engine that was "preventing" leaks...so after flush, sludge removed....leaks start to happen. but i guess this way, at least u know that ur engine has leaking problem rather than letting sludge "fix" the problem rite?