So my 02 4runner is approaching 200k miles, and most of the mileage services on it have been completed, with the exception of replacing the transmission fluid. I was hoping to take it out this weekend, weather dependent, which will play a little more into the situation and my questions here in a minute. After reading a couple of threads, Im split on a couple of options.

Question 1: Should I do a complete drain and replacement of all fluids in one shot, or should I simply drain the pan, drive it for a few miles, then drain the pan again? This would be pretty time consuming and taking the skid plate I have over the transmission would be a huge PITA. I know a lot of people on here will replace their fluids over a few hundred miles, draining and filling in increments.

Question 2: Additionally, Im not sure if I want to go wheeling with half changed transmission fluid. Would that affect the running of the vehicle or potentially damage the transmission?

Question 3: Should I go for the full removal of the pan and swap out the filter/screen and clean the magnets? Im not so much worried about the extra labor, as the possibility that I screw something up, and leak out half my transmission fluid deep in the mountains. How significant is dropping the pan and cleaning the magnets/screen?

Where we are looking at wheeling/camping would be best case, about a 2 hour drive back to a paved road, that I dont want to do god forbid Iv lost all my fluids. I will be bringing 5qts of Trans fluid as a typical part of my usual kit, but i have no idea how fast a transmission can dump its fluids.

After reading This thread Transmission flush?,the response by @004runnerLtd , and This videohttps://www.youtube.com/watch?v=RumP...EUXKFzzaT&t=0s, I am leaning towards doing the full drain and fluids replacement at once, but certainly open to input from those who have done this one before.

Opinions and experience are greatly appreciated.

My choice: go for the full removal of the pan and swap out the filter/screen and clean the magnets. If you still need more guidance I'd recommend going to the 3rd gen section for more specific advice, this section can move very slow sometimes.

After changing the fluid and filter, I did a 2 minute short start/run through the gear and shut down, get the fresh fluid into the system, while allowing more old fluid to flow into the pan, then did a drain and flush on my 4th gen 2005 4Runner, I'd like to think I replaced about 7 1/2 quarts, the stuff I did drain was quit dirty too, so I think it basically worked. I also added some Lucas transmission fluid conditioner. That was last summer, then this summer I just did one more drain and fill, it removed more dirty fluid, and added another Lucas conditioner.

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