Hi there - I have a 2016 Toyota 4Runner SR5 and it's due for an oil change. I am wondering about changing the transmission fluid. Well, not changing the fluid, but a drain and refill. And rear differential fluid change too. But I'm not sure if the transmission fluid has ever been messed with. I'm betting not, but I'm not sure. I haven't done it since I've had it, and I've had it for 2 years. 

The reason I'm wondering about changing the fluids is that I'm at 124000~ miles. I don't plan on getting rid of the car for some time, so I want to do proper maintenance. But I know that sometimes if the transmission fluid's never been touched, it's best not to mess with it. Just wanted some input/feedback before having the work done. Thanks in advance 😀