Fluid Flush Fallacy If you take your car to a shop for a routine oil change you have a high probability of being told your car needs one or more of its critical fluids flushed, changed or serviced.

In fact, General Motors states that the use of external transmission fluid exchange or flush machines is not recommended for automatic or manual transmission.

General Motors advises against using external transmission fluid exchange or flush machines. There are fewer convertible choices today compared with 2013. A four-cylinder engine can perform like a ...