Transmission fluid change via multiple drain and fills?

02FailBlazer

Member
Joined
Aug 8, 2025
Posts
60
Location
U.S.
Want to replace my transmission fluid, looking for an optimal method. If I bought a transmission pan with a drain plug, could I just do the following -
  1. Drop pan, replace filter, bolt on new pan with drain plug
  2. Top up fluid, idle engine in gear for a few minutes to circulate fluid, drain via drain plug
  3. Repeat step 2 until fluid is clear and of appropriate color
  4. Allow transmission to fully cool, top up to cold fill line
Is this fine to do? I'm aware of the cooler line method but it makes me a little nervous. Guess I could always stop earlier than necessary and top up, then repeat until the fluid is clear and red?
 
You can do it either way, that makes you feel good about it. How many total miles and miles since last filter/fluid change?
 
  • Like
Reactions: Mooseman
That way or a little quicker this way:


or

 
You can do it either way, that makes you feel good about it. How many total miles and miles since last filter/fluid change?

I've put about 35K miles on it since I've owned it and have no idea what the previous owner did. Never done a fluid/filter change on it myself.
 
  • Wow
Reactions: movietvet
That way or a little quicker this way:


or


The first video is the cooler line method I mentioned - am I overestimating the risk involved in doing that? Just makes me nervous that I could accidentally run it dry for too long and blow something up. If it is fairly safe to do it that way then that's probably what I'll do.
 
  • Like
Reactions: movietvet
The biggest thing to do with the cooler line method is to ensure the line is fully seated in the rad when you reinstall the little e clip. Thats it. Just push it in and you will feel it bottom out. After the clip is installed, give it a pull and will reveal if succsessful. There is a touch of play but you will hit the clip and it stops.

You will drain your pan the easiest for a filter change and clear out the most old fluid with the least loss of new fluid. Don't sweat it.
 
  • Like
Reactions: movietvet

Forum Statistics

Threads
24,245
Posts
648,359
Members
20,680
Latest member
rami

Members Online