Anybody have experience/opinion on Toyota's claim that their transmission/transaxle oil is lifetime and does not need replaced?

Never heard of that you talking auto or stick?

Wife's 2016 rav4-no tranny dip stick anymore so called dealer. They said unless you are having "problems" or drive under what they
call "severe conditions" it is generally lifetime. My old reliable transmission guy retired,but he used to laugh at lifetime oil claim,dealer
said the earliest they would ever change is 100,000+ miles-car has 91,000 on it

The problem with Toyota is my truck came with 6 manuals thicker then a NY phone book when stacked.

I don't know about toyota specifically but other manufacturers have similar claims and the problem isn't that the oil doesn't hold up. The problem is that it gets contaminated with dirt and debris and or it gets hot and burns.

I looked in manual and it read to inspect transaxle oil at 60,000 and 120,000.There is no dipstick to look at oil color,so that is why
I called-dealer saying lifetime

Research what qualifies as severe conditions. Most of us will fall into the severe driving condition category.

Really no such thing as lifetime fluid. Even if there's no dipstick, there has to be a way to check fluid level and condition. If you wait until you're having problems to change fluid, it's too late. Either start a fluid change schedule when it's new or leave it. When a transmission is really worn, sometimes I he grit in the fluid is the only thing keeping it from slipping, and I've seen before where a vehicle drove into the shop under its own power, trans fluid got changed, and it turned into a box full of neutrals.

Thanks-my old tranny guy said same things. All driving is severe and there is no lifetime oil of any kind. I researched checking the fluid
and it involves too much let alone can only be done when fluid is 104 degrees. I will have to take one and go to dealer

Manufacturers sometimes have really specific procedures for checking fluid levels. Usually a specific temperature. Dodge even has a universal dipstick. Their vehicles have a dipstick tube with no dipstick,and you're supposed to warm up the fluid to a specific temp which you can only check with a scan tool, and then shove the dipstick down and measure how far up the fluid is is millimeters and then compare that to a chart in the service information. Some Ford's have a little 3 inch long dipstick that you have to access by raised by the vehicle up, again only at a specific temperature. A lot of manufacturers have you check it by removing a plug in the side of the transmission and filling it up through the hole until fluid runs out.

I believe that's what I enjoy the most about this forum-there is always someone that has the experience to answer any question.
Thanks

mine start to slip a little bit before it was warmed up so at 200,000 had the tranny flushed and new oil hasn't slipped since now has 250,000

Always take a vehicle manufacturer's recommendations with a grain of salt.

They make vehicles to sell. They don't make money from service. They don't want vehicles to last forever.

If they can sell a car that "never needs service" that is a bonus to them.

If they are wrong the warranty won't cover it so they have nothing to lose.

Wife has a Lexus, I have an EcoBoost. Don't think either of us has a tranny dipstick. May be wrong. Both have less than 50,000 miles now.

I remember the wife owning a GMC Envoy with the straight 6 engine. Took it to the dealership at about 100,000 miles and had every belt, hose, and fluid replaced. They thought I was crazy. Sold it at 265,000 ten years ago and I think it is still running.

I had a 2007 Tundra that I bought new. At around 50,000 miles I took it to a transmission shop because I couldn't find anything in the maintenance schedule about servicing the transmission. He called Toyota and was told that it did not need service for life. He recommended that I bring it in at 100,000 miles anyway. I just forgot about it and never had it serviced. Sold it a couple of years back with 350,000 miles without a bit of trouble with the trans. I bought a new 2018 Tacoma and asked the salesman if the transmission had to be serviced. He laughed and said" of course " . He didn't know anything about the Tundra not needing serviced.

I have an 07 Tundra and changed ALL the fluids when I got it at 112K. Don't believe in the lifetime. If it doesn't last a lifetime they don't warranty it. Changing the trans fluid isn't too bad: Mark a bucket in quarts, disconnect the trans cooler line and run a hose from it to the bucket, run the engine and have someone watch the bucket, when it hits 3 qts they hollered and I turned it off, had another hose with funnel running from the top of the engine down to the trans where the filler hole is, put in 3 qts and did it again, did that for 12-14 qts and was done. Transaxles and transfer case were simple drain and fill. What model and year do you have?