ATF Service

Before someone mentions that similar threads are out there, I want to clarify that I am searching for newer input on the topic. As I am fully aware, fluids need to be changed alongside a general tuneup if one wants their vehicle to perform optimally. I am currently in the process of performing maintainence on my '07 Prerunner considering it has reached 100k and continues to climb. The previous owner(s) did little to no maintaince besides oil changes and tire rotations. I changed the spark plugs last weekend to note that it still had the original plugs! (NGK on driver's side and Denso on passenger) I've changed diff fluid, cleaned throttle body and MAF, and possibly looking at a serpentine belt soon. Skipping ahead, I'm wondering about the transmission fluid. I sought out a local "professional" that claimed that the transmission should be left along unless serious troubles arise considering it has high mileage. I understand many on here will say "fluid deteriorates, so change it." Even though I understand your side, how many on here have yet to service your transmission? The local tech said the transmission could very well start slipping if new detergents are placed inside, so I'm confused on whether or not I should even touch it. Please feel free to leave your thoughts!

 

Anyone?

 

I don't flush my transmission at all. I just drain the pan and put in a fresh 3+ quarts every other oil change. Overkill but it's cheaper than a new trans. I use Valvoline max life synthetic. I do that on all my vehicles and it works out to once a year.