I just got a 98 Mazda 626 2L and need to flush the atx fluid, it's really dirty brownish red, but not burnt and I didn't notice any particles in it.
I think the car has a CD4E tranny ( it turns out to be a GF4A-EL actually, but I don't think that matters ), and I've heard they have internal filters which can't be changed without dropping and disassembling the tranny.
I came across this procedure for flushing the fluid, and wanted to know if it's safe. I'm worried that running the transmission with the inlet line disconnect could damage something due to lack of lubrication.
Tools required: pliers, 10mm socket, milk jug, transmission fluid funnel
Parts required: 1 case of MERCON transmission fluid
Optional: get a new 1/2" screw-down hose clamp to replace the cheap factory hose clamp.
- Drive car up on ramps.
- Remove the drivers-side black plastic underbelly pan (held on with several 10mm bolts). This exposes the 2 hoses running to the transmission from the transmission cooler.
- There are 2 black rubber hoses running from the external transmission cooler in the front of the car. Each one attaches to a metal tube that attaches to fittings on the transmission.
- The tube attached to the front of the transmission is the outlet (i.e. fluid is discharged from the transmission here).
- The fitting in the rear of the transmission (and also closest to the front wheel) is the inlet (i.e. fluid enters the transmission here).
- To flush the transmission and the external cooler, you need to disconnect the rubber hose from the metal pipe that connects to the rear of the transmission (the inlet).
- Identify the transmission inlet hose, and remove the hose clamp with pliers.
- Pull the rubber hose off of the metal pipe. Some fluid may come out, but there won't be much.
- The idea of a transmission fluid flush is to use the transmission's own pump to pump out old fluid, and then replace it with new fluid. I used a 1-gallon milk jug to collect the old fluid, and a helper to start and stop the car's engine on my command.
- Position milk jug under disconnected inlet hose, and have helper start engine. Fluid will pour out of the inlet hose into the milk jug. Stop the engine when approx 2 quarts have come out (the milk jug is 1/2 full). This will take 15-20 seconds or so.
- Add 2 quarts of new transmission fluid into the dipstick tube.
- Repeat steps 4 and 5 until the transmission fluid coming out is the same color as the new fluid. For me, it took a full case (12 quarts) of fluid. At least one time during step 4, have the helper shift the transmission into R and D while the engine is running.
- When all fluid has been replaced, reconnect the rubber hose onto the metal pipe and install a new screw-type hose clamp (the factory clamps are junk).
EDIT 2/1/2016
I was thinking that I could connect a second hose to the other side and while old fluid is draining, stick the second hose in a jug of new fluid and let it be sucked up while the old fluid is draining out.
If I want to drop the pan and change the filter, how would I modify this procedure so that I don't waste too much fluid?