How do you flush the transmission?

Answer 1

If you need to "flush" the Transmission Fluid, then it is time to change the filter too. Do not just drain and change with a drain plug bolt (if it has one) The filter must be changed every 50k and the pan cleaned out.

Find a level, flat concrete spot to do this. PUT CAR ON JACK STANDS or ramps!!!!Never get under a car that is on a jack! Many, many people have been crushed to death this way. Never trust any jack!

Buy a filter and gasket kit, and 5 or 6 quarts of trans fluid.

Remove dipstick.

If there is a drain plug bolt, then drain the trans using it if you want and disregard the draining steps with last bolt below and just remove all of the bolts holding pan on...

Remove the (prob. 10mm) bolts that hold the trans pan on around the edge of the whole bottom of it. (like 15 or so of them) Leave the last bolt tight.

Put drain pan below. Fluid is going to come from opposite side of pan from that last bolt.

Now, undo the last bolt a few turns and on the opposite side using a small prybar or screwdriver break the pan free from the tranny. DONT HARM THE ALUMINUM FACE OF THE TRANNY WITH THE SCREWDRIVER. The screwdriver wont scratch the pan side, so pry against that. If it takes much effort you need to check that there are no other bolts holding it on. You will definitely know when the pan separates from the trans. once it is free, start slowly unscrewing that last bolt. Fluid will drain, and when it stops unscrew it a little more so more comes out, repeat until its only enough left that you can just remove the bolt and lower the pan completely. Theres a lot of fluid in there so I suggest doing it like I said. You could simply remove the pan in one shot from the start, but you will have quite a mess!

Once pan is down and fluid is drained, remove fluid filter. Make sure filter gasket came off with it. Install new filter. Careful to have no dirt on your hands that can get on this. Take pan and clean it free of any dirt, grease, etc.. There might be a magnet in it. clean and replace. Make a note of how much crap is in the bottom of the pan too. The more there is, the more wear there is in your clutches and bands. If there are any chunks of metal in the pan that is NOT good. A small amount of metal filings is normal.

Do not ever use any type of gasket sealant, silicone, or adhesives unless it is specifically meant for transmission gaskets. None exists that I know of. The stuff will not work and will plug up your transmission and cause physical damage. You should never need that stuff on any gasket anyways. I never use it on anything.

Put the Trans pan gasket on the pan and if you need to you can put a bolt in one hole to keep it lined up. Hold the pan up to the trans and line up that bolt hole. start the threads and make a couple turns. repeat on opposite side and line up gasket with bolt. If gasket came in a flat package then you probably wont have much trouble but if it came in a ball shoved in a box, then you'll have to do each bolt in a star shaped pattern to keep gasket lined up.

When all bolts are in, start tightening them all, but not more than hand tight.

(not that you cant use a ratchet, but once seated do not tighten the bolt more than you could by hand). When bolts are all 'hand tight', you can start tightening them one by one after you can see the gasket is correctly in place.

Now, remove jack stands or ramps and make sure car is level. (not on a hill or jacked up)

The fluid is replaced through the transmission dipstick tube. You must use a transmission funnel or one that fits in the tube for dipstick. I would pour in 5 quarts then start the car and check the level. If you got to this point you should already know how to check your trans. fluid and add, so ill spare you the details. After it is full, cycle through all gears using gear shifter in car and then check one last time that fluid is full. Do not over-fill.

Last, make a note of how dark fluid was, if it smelled burnt, and how much clutch dust was in the pan. This tells you the condition of the transmission.

enjoy