Originally Posted by LexFinally (Post 11951302)

... Our 2010 Prius recommends thin oil here, yet the mechanically identical car has a thicker oil recommendation in Australia. Yes, Australia is a hot place, but there are hot places in America too. So, which country's Toyota management do you believe?

Similarly, customers want maintenance-free cars, and they're more eager to buy one if they think that's what they're getting. it's an irrefutable fact that lubricating fluids do deteriorate, use up their additives, and circulate impurities during their lifetime. Yet Toyota, a brilliant engineering company, recommends that the fluid never be replaced. Toyota didn't used to do this. Has there been a quantum leap in torque converter technology or fluid performance to explain this? Maybe it's more like that 2010 Prius, which came recommended with a 10,000 mile oil change interval for "normal" driving. Yes, in the fine print the definition of "severe" driving was so wide-ranging that it included almost everybody, but the damage was done. A whole generation of Priuses and Corollas, equipped with the combination of fragile new piston rings and a reckess factory recommendation, now lose oil like sieves.

Nobody in a capitalist society is 100% pure and free of having their behavior influenced and sometimes distorted by the profit motive. And while Toyota does a better job that most -- which is why we own two -- in a capitalist society, it's caveat emptor...

Originally Posted by artbuc (Post 11951332)

Chris, congrats on new 2025. Please let us know how she performs.

Originally Posted by chrisexv6 (Post 11951223)

What is interesting is that even if you drop the pan completely, you're basically just doing a drain and refill anyway. The bulk of the fluid (in any torque-converter-based automatic transmission, even "serviceable" with a dipstick) stays in the torque converter. So at best you're taking out about 1/3rd of the fluid, maybe a little bit over, even if you completely drop the pan (confirmed by your excel sheet values)

Inefficient, absolutely. But like you said its really the only way in pretty much all cases. Our old Acura was known for transmission issues, so I resorted to a drain/refill every other oil change. Luckily, it was basically a 15 minute thing because dipstick, fill from the top, drain from the bottom. 3 quarts out, 3 quarts in, run up to temp and check level on the dipstick.

Technically the Toyota/Lexus 6 speed is the similar, ultimately its just a bit tougher to read the level. Draining isnt too bad as long as you have the right hex/torx bit and dont overdo reinstalling the overflow tube.

Originally Posted by rmak (Post 11951358)

I have 105k on my 2016 ES 350 and have dropped the pan twice. The filter is a paper filter element like most others so I dropped it to change the filter and clean the pan magnets. Very easy to do and helps shifting smoothness. I also do a drain and fill every 10k (every other oil change) with amsoil now. If you do it early and often, it will also keep the solonoids from getting clutch debris all over them.

Originally Posted by rmak (Post 11951358)

I have 105k on my 2016 ES 350 and have dropped the pan twice. The filter is a paper filter element like most others so I dropped it to change the filter and clean the pan magnets. Very easy to do and helps shifting smoothness. I also do a drain and fill every 10k (every other oil change) with amsoil now. If you do it early and often, it will also keep the solonoids from getting clutch debris all over them.

Originally Posted by chrisexv6 (Post 11951379)

Ive watched a few YouTube videos on the process and it always seemed to be a PITA to remove the one pan bolt that is blocked by the crossmember. Is that not the case on the 2016 (and, hopefully, my 2015)?

Really didnt want to go through the rigamarole of lifting the engine up ever so slightly to get that last bolt out.

Originally Posted by artbuc (Post 11950663)

No analysis on additives. Not sure if this report tells you much.

Originally Posted by grp52 (Post 11951478)

….So, examining the value of the "ATF Thermal Degradation Estimate" with a scan tool is a means of estimating whether or not the automatic transmission fluid is suspected of being thermally degraded to a degree recommending automatic transmission fluid replacement.

Originally Posted by scubapr (Post 11951355)

Thinking about how this from a business angle; most automakers and dealers now offer extended free maintenance. I got 48 months or 50K miles of complimentary service. But there’s a big cost difference between giving five oil changes at 10K intervals versus ten at 5K OCI. And since now "lifetime" transmission fluid does not need to be replaced before 60k at min, it’s a profitable cost-saving strategy all around. :rolleyes:

Originally Posted by artbuc (Post 11951520)

Looks like algorithm that considers frequency, magnitude and duration of temperature spikes…maybe other factors too. Great find!

Edit: Just read on Tundra forum…2016 with 20k miles, never towed or worked hard. ATF Degradation Estimate over 65,000. Go figure.

OBD adaptor arrives today. Car Scanner can read ATF Degradation Estimate, not sure if my 2020 provides it. Will report back.

Originally Posted by alextv (Post 11951692)

I have never heard of this ATF Thermal Degradation being on scanners is that something new? I have the scan gauge and techstream is it on those also?

Originally Posted by ESh (Post 11947499)

WS fluid.
104-113F.