View Full Version : Transmission Fluid Change

03-20-2004, 01:43 AM
What is the best (proper) way to change the transmission fluid on a direct drive? How much fluid does the change take? I have a 2000 Air with the GT-40. Thanks

03-20-2004, 07:42 AM
There is a drain plug located at the bottom of the back side of the transmission. It is nearly impossible to get to this plug with the engine in the boat though (I tried on my old boat). The generally accepted method is to use a hand pump to pump out as much old fluid as possible through the transmission dipstick hole. Measure how much fluid you get out, and add exactly that much new fluid. Warm up your engine and then check the fluid level (Do this ON THE WATER). Your transmission should be filled with Dexron III only.

03-20-2004, 05:38 PM
When you go to check the level, you need to shift the boat into forward a couple of times and shift it in reverse a couple of times and then double check it. The most you will ever put in the 1.23:1 trans is 2 quarts. If you are using a hand pump, chances are that you won't get 2 quarts out of it. Most likely it will be just over a quart that you get out.

03-22-2004, 12:41 AM
Hey Jeff, where did you get that info from? Those numbers are not consistent with what I know. I'm going to research further at work tomorrow. From what's in my head, V-drive = 1 quart, because there is not reduction, and a direct drive or 1:23:1 is 2. An oil evacuator is the best thing to use if you can get to one, or a pump of some kind that has a probe long and narrow enough to make it past the guide hole.

03-22-2004, 12:50 AM
That information came from a PCM Ford 351 Engine Owner's Manual. I don't have it in front of me right now, but I believe it was printed close to the end of the time PCM was using Ford engines.

03-22-2004, 08:53 AM
D-drives are 2 quarts, V-drives trannies are 1 quart. V-drive is 1 quart (30wt) What I did on a recent tranny fluid change was to use a hand pump but, I put about 8" of 1/4" brass tubing stuck inside the rubber tubing coming off the pump and I was able to get the tube down to the very bottom of the tranny and pulled out 2 quarts. Also only use Mercon III rated ATF fluid.
Fluid Level:
Put the dipstick down the the first O-ring and then check the level. Do this a few times to make sure because it's hard to read on the dipstick.
Put the dipstick all the way in. Again do this a few times to be absolutely sure.


03-23-2004, 02:36 PM
I have found the best way to get old tranny fluid out is to buy a vacuum pump designed for one person brake bleeding. You can buy these at auto zone for about 30 bucks. Just stick the tube down the dipstick hole until it hits the bottom and vacuum fluid till the vacuum pump barrel is full, dump it out and then repeat the process (many times) until you get it all out. Just fill up the tranny with new fluid. I have had great success with only a minimal amount of residual left in the tranny.

12-29-2004, 08:37 PM
I also have 1.23:1 trans. Manual states 2 Qts to refill. After draining i put in about 1 3/4 Qts. thinking i would check and top off to finish the job. The dipstick at rest on 1st o ring says i am already over full. Has anyone else experienced this??
I warmed engine and drained tranny from the 7mm drain plug underneath so as to remove all trans oil. I did not measure amount that i removed.

12-29-2004, 09:44 PM
You need to run the boat and cycle it through forward and reverse a couple of times. If you pulled that plug, you should have got most of it out. Try cycling through forward and reverse and see where you get.

12-30-2004, 02:05 PM
Thanks skinautique i will do that today and re-check.

08-26-2005, 01:37 AM
I was stupid and forgot the plug in the boat, filled up the engine compartment just below the computer module in the back - yes it was stupid. Now, I need to change the fluids so I need help.

I have a 210 SAN, I put in one quart of tranny oil and will check it while on the water. Do you check it while sitting in the water - level? It should read between the two lines right after it has been pressed all the way in? I felt the botton of the tranny and I could not find any drain plug, where the heck is that plug? I have a "suck up" pump that works great but nothing like the drain plugs.

When I changed the Vdrive (Walters) I put in quart of 30w, how do I check that - while on the water as well? There was a 10mm square bolt in the back of the v-drive and it drained perfectly.

Do you check the engine oil the same way in the water?

OR, can you do all this on the trailer - smile.

08-28-2005, 12:15 PM
When changing the oil, make sure it is warm.
I use the ITT Oil Change pump, which has female garden hose threads
on the intake. You then buy some brass fittings ( Weatherhead or Fairview) and some nylon tubing and compression fittings, and if you are
reeeeallly patient, you can get the tubing to go right into the sump of the
transmission. It is pretty hard to do with boats up to 95, because of the
muffler that sits above the transmission. 96 and up, it's easier.

Some of the older boats, used 20W oil, which is hard to find. I changed my oil twice to flush it all out, so I can use the more readily available
Dexron III.

Keep in mind the trans oil cooler has a bit of oil in it, as do the hoses going to it, so you can never get it all out.

Hope this helps.

08-28-2005, 04:28 PM
Check ebay. There are usually several new battery operated suction pumps for sale. I picked one up for $17 that comes in a box with various hoses including hoses small enough to get down through the guide tube.