Transmission fluid change? Leave alone or change?

My 2016 Tacoma Pre-Runner Quad Cab V6 2wd automatic has almost 170,000 miles on it. I keep all my service receipts BUT I don't recall ever changing the tranny fluid. MAYBE I did the initial tranny fluid change early on?

I've been told "leave well enough alone". 1) Should I drain and change the tranny fluid now?
or 2) Do a complete drop the pan and have it cleaned and change the fluid? 3) Just leave it be?

I towed a double jet ski trailer for 5 or so years and had a small travel trailer (1,700 lbs. dry weight) that I took on 3 short trips. (Before I realized it was too much for my Tacoma to haul!)
Man, my Tacoma just did not like hauling even a small travel trailer! Got rid of the travel trailer and picked up a Minnie Winnie.

Transmission drives fine, not issues.
Appreciate the input

 

Your Tacoma manual states you should be flushing your ATF every 60K if you tow, among other conditions.

At this point, I would replace the ATF filter and do a flush only if you don't find any clutch material or metal flakes in the trans pan. To do so otherwise make cause your trans to slip.

 

So you recommend pulling the pan?

 

Spill and fill a couple times, call it good

 

Yea. What BRO said. Every60K when towing

 

Under no circumstances would I run a machine as critical and complex as a transmission without preventative maintenance.

Life is simple. Prevent or wait to detect the problem later...

 

Yes, pan has to come off to replace the ATF filter. At which point you can inspect the pan for debris. There will be two or three magnets inside the pan. It is normal for them to have a slimy black sludge. If thats all you find, it is generally safe to proceed with a drain/refill or flush. As mentioned above, avoid shops that use a pressure machine to perform the flush which could dislodge trapped material to come loose and plug orifices.