Thank God!
When I took my friend’s 2008 Rav to the Toyota dealership for an AT flush, I actually had to argue with the service writer, who was insistent that the fluid was “lifetime”. I won, but I was astounded that it took so much effort to get them to agree to do it.
Several years ago I read a long-term study by an aftermarket org that monitored transmission life. They studied 2 groups of cars from the same manufacturer. One group changed the fluid every 30,000 miles. The other group did no service at all.
There was no statistical difference in the rate of transmission repairs or failures between the 2 groups until about 140,000 miles. After that the group that did no services had an increased rate of failure, while the group that changed fluid did not. No surprises there.
But if we consider the useful effective life of a typical car to be 120,000 miles (as is done for warranty or legal purposes), the argument could easily be made that there’s no need to service the transmission.
You make a very good point . . . if someone is planning on buying a new car and trading in at 120K
But if you’re buying a used car . . . I’d hate to be the one buying that freshly traded-in car with 120K which has never had its atf serviced
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Welp here is the pdf owners maintenance manual for a 2023 Tacoma… Only recommends changing the ATF under these conditions:
Driving while towing, using a car-top carrier, or heavy vehicle loading:8
Replace front differential oil (4WD)
Replace rear differential oil
Replace transfer case oil (4WD)
Replace transmission fluid or oil
Tighten nuts and bolts on chassis and body
In 2014 there was no recommendation for tranny fluid change just like my Highlander. Now there is a recommended change under certain conditions. I personally change fluid every 50k miles.
If there’s a leak, and the low-pressure switch is preventing the compressor from running, there is no need to recover the trivial amount of refrigerant which is left in the system.
Obviously, after replacing the hose and O-rings, you will need to pressure-test the system with dry nitrogen, then evacuate and weigh in new refrigerant. I would recommend replacing the dessicant bag, but some people don’t bother, and hope for the best.
I believe that the EPA Section 609 Certification which we are all required to have states that any amount of refrigerant must be captured using EPA approved RRR equipment. Now as far as what happens in real life… 
There’s a real lack of long-term consistency regarding drier or dessicant service. I have enough gray hair that I remember being taught that any time a system is opened at all, you replace the drier. Now, many OEM service manuals specifically tell you that dessicant replacement is not required unless there is system contamination.
I’ve never pressure tested an AC system with nitrogen.
Once it’s assembled, I draw vacuum on the system until it reaches 28"-30" hg, close the manifold valves, turn off the vacuum pump, and let it sit for 15 minutes to see if there’s a pressure drop.
After which, I turn the vacuum pump back on, open the valves, and continue to pull a vacuum on the system for an hour.
Then recharge the system.
Tester
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What he said… 