In the last few years a new service started to be recommended by quick lube places and some dealerships. This is the engine or transmission flush. So I am often asked if this is needed or not. Well, let me explain what a flush is and then answer the question.
What is a flush?
An engine or transmission flush is basically done by forcing cleaning fluids through the engine or transmission. Yes, I did say forcing. This is done with high pressure machinery.
Does a flush improve performance?
No, a regular oil and filter change or an oil change with a flush give about the same results in performance yet one costs about ¼ of the other.
Does a flush increase the life of your engine?
Keeping the engine clean does increase the life of the engine, that much is true. So in theory, flushing the engine would increase its life, but there is one problem with this: the moment you start forcing solvents under high pressure through anything, you risk damaging it and if it does get damaged, would you have increased its life? Probably not.
The truth of it is that a simple oil and filter change done regularly accomplishes the same end result (a clean engine) without risking damage.
Do car manufacturers recommend engine flushes?
Well, Honda, Ford, GM, Nissan and many others actually don’t recommend it and in many cases they advise against it. Anything that your car manufacturer recommends is covered in the owner's manual of you car. If it’s not in there, it’s not recommended.
So the next time you get told your car manufacturer recommends a flush, pull out the owner's manual of your car and ask them to show you where.