An automatic transmission changes the gears, engages and disengages the transmission and downshifts the vehicle's engine without requiring the driver to use a clutch or gear shifter. Transmission fluid is responsible for lubricating and maintaining a proper internal core temperature of the transmission. Transmission fluid should be changed every 50,000 miles under typical driving conditions. Replacing transmission fluid can be cumbersome, and requires dropping the transmission pan and changing all of the gaskets and filters. To avoid these extra steps, the fluid may also be changed via the transmission's dipstick tube.
Remove the dipstick from your vehicle's transmission.
Feed the input tube of the petroleum siphon pump (see Resources) into the dipstick tube until it reaches the bottom.
Pump the fluid out of the transmission, placing the output tube into a bucket for collecting the old transmission fluid.
Remove the siphon tube from the transmission dipstick tube when all fluid has been removed.
Place a funnel into the dipstick tube, and pour in one quart of fresh transmission fluid at at time, checking the fluid level with the dipstick after each quart. Repeat this until the dipstick reads full.
