How to Complete a Transmission Flush

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How to Complete a Transmission Flush

Like changing the oil and switching tyres, draining and replacing a vehicle's transmission fluid is part of regular preventative maintenance. One way to do this is with a transmission flush. This process completely removes the old transmission fluid along with any dirt and debris it collects, making it possible for the owner to fill the transmission with fresh fluid. Although some people opt to let a mechanic perform this task, those who have the right tools and understand the process have the ability to complete a transmission flush at home.


Gather supplies

In order to flush the transmission, a vehicle's owner needs either a jack and jack stands or ramps to lift the car and a block of wood to keep it from moving. Additional tools to have on hand include a screwdriver, wrench, and socket that fit the clamps used on the transmission, as well as a large drain pan, a long, narrow funnel or transmission fluid pump, rags, and transmission fluid. Some people also like to use empty milk jugs to measure the amount of fluid they remove from the car so they know how much to add.


Prepare the vehicle for a transmission flush

Before flushing the transmission, vehicle owners must have access to the transmission from under the bonnet and under the car. This means they need to lift the car high enough to give them space to work underneath and make sure the car cannot move while they work.

Options include lifting the car with a jack and resting it on jack stands, or driving the vehicle up a ramp that lifts the front end. In either case, make sure to block the rear wheels by placing a block of wood behind the tyres. After positioning the car, turn the car on and off once the engine warms up to its normal operating temperature.


Remove the old transmission fluid

The first step in the transmission flush involves removing the old fluid from the transmission along with the dirt and debris collected in it. This also provides an opportunity to inspect the transmission fluid. Normal fluid is red in colour, while old or burned fluid is dark. Pieces of metal floating in the transmission fluid indicate a problem with the transmission that requires professional assistance.

Using a transmission fluid pump

A transmission fluid pump makes it easy for owners to remove the fluid from the top of the car. Remove the transmission dipstick from the top of the case and insert the pump's vacuum tube directly into the transmission. Following the manufacturer's instructions, operate the pump and let it draw the fluid out into the drain pan.

Using a funnel

Those who cannot locate a transmission fluid pump may choose to manually remove the fluid. Start by disconnecting the transmission oil cooler lines that run between the radiator and transmission, letting the fluid collect in a drain pan. As the fluid drains, remove the dipstick from the top of the transmission and place the funnel in the fill tube.

With the engine running, pour 9 litres of transmission fluid into the funnel without stopping to let the funnel dry, and turn off the car after pouring the last litre. This lets the fluid clean the transmission as it enters and exits the system.


Refill the transmission with new fluid

After removing the old fluid from the transmission, refill the reservoir with new fluid. Each car manufacturer recommends a specific amount of fluid for each make and model they produce, so it is important to check this information before refilling.

Another way to determine the amount of fluid to use requires empty milk jugs. Pour the oil from the drain pan into one empty milk jug and fill the other with new fluid until both jugs have level fluids. To make sure the transmission has the proper amount of fluid, turn on the vehicle to let the engine warm up before checking the dipstick. If the dipstick indicates low fluid levels, owners should add no more than 1/3 of a litre.


How to buy transmission supplies on eBay

Keeping your car running properly is simple with the transmission supplies available on eBay. To locate the items you need to complete a transmission flush, enter descriptive terms like "transmission fluid pump" or "automatic transmission fluid" in the search box and click to see what sellers have to offer. Look for deals like bundles and sets that include all the pieces you need to perform the flush, and read descriptions carefully so you find compatible parts for your vehicle.

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