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Engine Flush

When I had my car in for an oil change, the mechanic said the oil was very dark. He explained that metal bits get in the oil from the ball bearings (hope I have that right). He suggested an engine flush (my car has never had one). My 2000 Nissan has 93,000 miles on it and is running great. What is an engine flush and do you recommend it? Also, how do metal bits get in the oil?

Have you changed oil on schedule in the past? Did you go to a fast-lube shop? Is oil just dark and did you see flakes of metal? Engine oil flush is unnecessary unless mechanic has a late boat payment. Oil gets dark especially after 3000-4000 miles…as long as you have changed oil on schedule your bearings should be fine.

Metal bits get in the oil the moment the engine is started at the factory. However, with normal maintenance, those bits are small, the filter filters them, and oil changes take care of the rest.

If you’ve maintained your car, it should never need an engine flush. Many of these “engine flushes” are being heavily promoted by shops because they are big profit generators. (They are also good at flushing your wallet).

Save your money - and do find a mechanic who is looking out for you and not him.

We have to ask which quickie lube place you took your car to… It goes with the territory. We hope you did not buy into the wallet flush scam. The “techs” in those places get a commission on every extra “service” they sell over the initial oil change. Most of them are too young (and inexperienced) to have boat payment past due, but they try anyway. Stories of their ineptitude abound on this website. See mine here: http://community.cartalk.com/posts/list/2136790.page

I think it is fairly clear that this “mechanic” is someone who engages in baseless scare tactics in order to extract extra money from unsophisticated customers.

Oil does normally become dark because its detergent additives are keeping carbon and other substances in suspension until the oil is drained. The oil filter helps to trap the larger particles, and the oil keeps the smaller particles in suspension.

If there are visible metal particles in the oil, then flushing the engine is not going to save it. Visible metal particles would mean that there is severe engine wear and the engine is near the end of its life span as a result of that excessive wear. Unless the OP was shown evidence of metal particles in the oil, then this mechanic’s statement is very dubious.

My only concern would be about the OP’s normal oil change regimen. If the oil is being changed according to the Nissan maintenance schedule in the glove box (using both the odometer mileage factor and the elapsed time factor–whichever comes first), then there should be no need for an engine flush.

A better salesman than your “mechanic” came into the shop and showed them a very nice way to increase profits. They had this machine, on the cheap of course, that they’d sell to the shop. If they sell X number of flushes per day/week/month then they’ll triple their “investment” within the first 2~3 month. So, this mechanic is pushing his customers into getting this flush to increase his profits using whatever means he can.

The only thing that gets flushed is your wallet…

That sounds like a fast lube place. Keep away from the quick change places. We hear far too many horror stories about them. Some may be fine, but many pay the help little, demand fast changes and that results in a high percentage of errors. Too many live by selling you something you don’t need at inflated prices.

Find a good local mechanic and stick with them for your needs.

Don't go to the quick lube places, even for directions.