Need advice Transmission Fluid: to change or not to change?

[mallard75]

I recently purchased an 04 with 150K and the fluid had also never been changed. I did a drain and fill (about 3-3.5 liters at a time) using Toyota ATF twice now within about a month and will probably now just switch to doing it when I change my oil. The tech at the dealership may have been told never to tell a customer to change the fluid on a vehicle that claims to have a lifetime fluid.

He never mentioned lifetime fluid. Turns out he is convinced it would create a liability and that I would blame them if the transmission failed after service. He is squarely in the camp that changing it now will destroy it. After the feedback here I’m not so sure. I feel much better about doing a couple drain and fills. I appreciate the discussion!

 

[BullElk]

But if you tow, have a heavy built vehicle ( mine is 6600lbs), you wheel it, climb mountain passes you'll want to fluid exchange 60k intervals per OM maintenance schedule. I drain & fill @ 20-30k intervals to keep cycling in some fresh fluid.

Agree. Curious to know how fluid looked before changing?

 

[Moderator]

Change tranny fluid every time you change your engine oil? Holy Toledo. I wonder how many more miles I could get out of my tranny's if I changed the fluid that often.

What I meant was changing it every time I change the oil until it looks clean or until I've changed it 5 times in total since there are about 16 liters of tranny fluid and I'm draining and filling 3 liters at a time. The first time I changed it, it was pretty dark.

 

[abuck99]

Agree. Curious to know how fluid looked before changing?

When I bought my 100-@164k I took it to an independent toyota shop here in town and had them exchange the ATF on the BG machine- it looked pretty dark. 25k later I did a 3qt drain & refill and what came out it looked pretty good (it should at 25k). I like to stay ahead of schedule on my truck.

 

[MikeK]

Toyota and dealerships seem to recommend every other preventive maintenance item in the book, so why not this? Toyota's brand and reputation is all about reliability. If it needed a tranny flush and refill, wouldn't they recommend it?? Imho color means nothing; what does an oil chemist, mechanical and hemodynamic engineer say regarding the functioning properties of 300K miles in a perfectly functioning tranny with dark fluid (vs 'fresh')? A friend of mine has a 2000 lx470 approaching 400k miles, he's never touched the transmission fluid (purchased at ~80k miles). My 2005 LC is approaching 200k miles (me/1 owner) and similarly runs, shifts, and drives flawlessly. Perfectly functioning. Time bomb? ...or just getting broken in.