It has been about 24K miles since the last fluid change in my manual tranny so I thought I would drain it down and put in some clean fluid. It is a rare day that I would ever run the chance of contaminating the fluid with muddy water since I never do water crossing deeper than about the hubs. Remember, I live in a desert out here. If it is flash flooding, you don’t cross the wash…..and better yet, stay home and wait the 30 minutes for things to dry back up again!
Doing a fluid change in the AX-15 tranny is pretty straight forward and requires the most basic of hand tools. A ratchet with the appropriate socket, 15/16″ if I remember correctly, to handle the drain and fill plugs is nice to have, although an open end wrench would work just as well. The black thing in the above picture is a suction gun and is perfect for sucking the new fluid out of the bottle and squirting it into the fill hole in the tranny. And of course, you will need your favorite brand of transmission fluid. I use Redline’s MTL synthetic tranmission fluid. I was running MT-90 but when I stopped at the performance shop this morning to grab some for this project, they were fresh out (go figure!). MTL is just a bit thinner than MT-90 and both are rated for GL-3 and GL-4 trannys, so either will work just fine in the AX-15.
ALWAYS open the fill plug first on what ever it is you are going to drain. Why? It really stinks when you drain the transmission and then discover you can’t get the fill plug out so you can put the new fluid in. Opening it first gets that possible nightmare out of the way.
Now that the fill plug is loose, I turn my attention to the drain plug. Just crack the drain plug open but don’t unscrew it more than a half turn. As you can see in the above picture, the skid pan is sitting directly below the drain plug and I know I don’t wish to dump 3 quarts of oil onto my skid plate. I could remove the skid plate but that is a hassle. Hmmm….what to do?
So….I have some of that aluminum flashing laying around the garage from the last roofing project. I keep a piece or two of it on the shelf with the other “oil changing” stuff for just these situations. With a little bend here and there, I make an easy to manage funnel that allows me to direct the flow right into the oil catch container. You could most likely do the same with several layers of tin foil (raid the kitchen baking cupboard but do NOT leave in oily fingerprints behind!).
This is the drain plug, as it came out of the tranny. It has a magnet mounted in it to collect the really fine particles that wear from the gears in your transmission. This stuff feels like silt and needs to be removed from the end of the magnet.
Much better! You can clearly see the magnet in the drain plug now. Amazing just how well the magnet works….it really does keep the particles from circulating through the bearings and gears.
That is about it. Replace the drain plug. Using the suction gun, fill your tranny with the appropriate amount of fluid. My AX-15 takes 3 1/4 quarts. Replace the fill plug and wipe off any drips. YOU ARE DONE! Make a note in your maintenance log as to the date and mileage so you’ll know when your tranny is in need of its next fluid change. Don’t forget to pat yourself on the back. The dealership gets WAY more than is reasonable for doing this little job.