Here's a breakdown of the options:
* Drain and Fill (Partial Change): This involves draining the fluid accessible from the transmission pan, replacing the filter (if accessible and recommended – check your owner's manual), and refilling with the correct type and amount of ATF. This method only replaces a portion of the total fluid, typically around 40-50%. It's less expensive but less effective at removing old, contaminated fluid. This may be suitable for preventative maintenance, but likely won't address significant fluid issues.
* Transmission Flush (Complete Change): This method usually involves connecting a machine to the transmission lines to pump out the old fluid and simultaneously pump in new fluid. This process circulates the entire system, replacing a much greater percentage (80-90%) of the fluid. However, there's a risk of dislodging debris that could clog the transmission if the fluid is severely contaminated. This should only be done by a qualified mechanic unless you're very experienced.
* Power Flush: This is a more aggressive type of flush that uses higher pressure to clean the transmission. While it is the most thorough, it also carries the highest risk of causing damage. It's generally best to leave this to professionals.
What you need to know before attempting ANY method:
* Year and Model of your Focus: The specific procedure, fluid type, and filter requirements vary depending on the year and model of your Ford Focus. Consult your owner's manual for the correct specifications.
* ATF Type: Ford specifies a certain type of ATF for your Focus. Using the incorrect fluid can seriously damage your transmission.
* Tools and Materials: You'll need a drain pan, new transmission filter (if required), new ATF of the correct type and amount, a torque wrench (for the drain plug and pan bolts), and potentially specialized tools for a flush.
* Safety: Working under a car can be dangerous. Use jack stands and follow all safety precautions.
Recommendation:
Unless you have significant experience working on transmissions, it's strongly recommended to have a qualified mechanic perform either a drain and fill or a flush. Improperly performing a transmission fluid change can lead to significant damage to your transmission, resulting in costly repairs.
The cost of a drain and fill is generally much lower than a flush, but a flush offers a more thorough cleaning. Discuss the best option for your vehicle and budget with a trusted mechanic. They can inspect the condition of your fluid and advise accordingly.
