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Transmission fluid replace or clean?

I notice in your guide to long vehicle life that you recommend replacing fluids as scheduled or before.

I recently took my 2005 Buick Lacrosse to the dealer for the scheduled transmission fluid replacement.

They convinced me that removing the fluid, flushing the transmission and cleaning and removing the fluid was better for the long life of the transmission.



Did I get sold a bill of goods?

No. A ATF fluid replacement “flush”, with a filter replacement or screen cleaning, removes the most old fluid. While some flush machines are fairly harsh, and that is why some folks recommend only a pan drop, filter replacement, fluid refill. I have had good results with both methods.

You didn’t mention mileage, but I would do a trans service every 25 to 30K miles. However, getting one done regardless of mileage at 4 yrs is also prudent.