been using engine flush in 5 of my cars including my skyline and not a problem and dont expect one, however if you are not sure then u can use an oil fortifier that prevents acidic build up from the minute amounts of oil flush left in the engine. but as said its down to preferance and if u dont want to use engine flush then dont but i have had no problems with it. and i flush and do my oil and filter every 4 thousand miles. :cheers:
also not wanting to sound rude BUT if there was a chance that the flush would damage the new oil dont u think that forte whos flush i use would not sell there products worldwide? and our garage uses 90% of there products now i have worked there for 9 years and i never known of an engine that has been damaged by a flush but again its personal preferance if u use it.
bear in mind this company will have spent millions and millions of pounds on research and development so to say it will prbally kill the new oil is i would say far fetched, but each to there own anyway my longest post yet phew

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