The UA80E (2wd) / UA80F (AWD/4WD) found in later RX-350's and Toyota Highlanders is an 8 speed multi-lock-up transmission and it's considered "Sealed for life" with no serviceable filter and no dip stick. Just a tad over 8 quarts is required to do a full exchange and just over 3 quarts to to do just whats in the pan (if it had one).
The transmission is emptied by taking out the #10 Hex bolt on the bottom of the transmission. Some fluid comes out and then you need a #6 long Hex to take out the plastic straw located inside the same hole to release the remaining fluid from the bottom of the transmission.
It comes filled with Toyota WS fluid by default which can run at 200F regularly not towing. The only time they recommend a change is in Severe duty situation which then it should be changed at 100,000 miles (160,000km) - Yeah like that was going to happen.
Once you have drained all the fluid you put the straw back in the drain hole just hand tight. Then fill the transmission using the WS bolt plug on the side of the transmission located behind a cover inside the drivers wheel well. This small cover is moved out of the way by removing the 2 bolts (10mm). It will take about 3 quarts. Fill until it spills out of the hole in the bottom where the straw is.
You also need to press on the end of the transmission thermostat located just under the radiator. There is a hole in the skid shield. Press on the end of it with a flat screw driver and then insert a small pin to lock it in the open position. This is necessary as the external cooler is only open to the ATF fluid cooling circuit when the fluid is at higher temperatures. It is necessary to make sure the external cooler is also full of fluid when correctly refilling the transmission as per Toyota Tech Info procedures.
Start the vehicle and put it in Drive with your foot on the brake for 10 seconds, then reverse for 10 seconds to fill the circuits with fluid. Then back in park. Then fill the transmission further until it spills out the straw again with the vehicle running still. Then with your scantool or Scangauge II with 4.42 software or higher and X-Gauge code for the Transmission Pan temperature. Wait until the fluid reaches 104F and reinstall the drain plug. Your transmission is now full to the correct level. Do not exceed 113F before putting the plug back in the bottom of the transmission or it will be under full. This temperature changes rather quickly in hot weather so be quick about it.
This is has to be done with the body of the vehicle level off the ground so you will need jack stands for the rear and front of the vehicle to do it properly. It's also best to do it when the vehicle is cold because it will quickly heat the transmission fluid back up over the 104F really quickly thanks to the coolant to ATF heat exchanger.
Simply removing fluid from the pan and pouring the exact same amount of fluid back into the transmission can have undesired consequences due to fluid expansion rates differing from Toyota WS official fluid and some other brand that meets this specification which is why it's best to fill and check using the procedure above. Toyota advises always using this method for refilling the transmission anyway.
If anyone has this transmission and has questions about this change procedure feel free to send me a PM.
I will tell you after having done this today on my UA80F transmission the Toyota WS fluid leaves a lot to be desired in terms of shift quality and I would highly advise using some other brand that meets the WS fluid specification. I chose Amsoil Fuel Efficient Vehicle formula which is meant to replace WS fluid, because I'm a fan of their transmission oils and have used them in the past with excellent results but there may be other quality manufacturers out there just as good.
Sorry I didn't think to take pictures of the process but when I drain/refill again I will take pictures.
The transmission is emptied by taking out the #10 Hex bolt on the bottom of the transmission. Some fluid comes out and then you need a #6 long Hex to take out the plastic straw located inside the same hole to release the remaining fluid from the bottom of the transmission.
It comes filled with Toyota WS fluid by default which can run at 200F regularly not towing. The only time they recommend a change is in Severe duty situation which then it should be changed at 100,000 miles (160,000km) - Yeah like that was going to happen.
Once you have drained all the fluid you put the straw back in the drain hole just hand tight. Then fill the transmission using the WS bolt plug on the side of the transmission located behind a cover inside the drivers wheel well. This small cover is moved out of the way by removing the 2 bolts (10mm). It will take about 3 quarts. Fill until it spills out of the hole in the bottom where the straw is.
You also need to press on the end of the transmission thermostat located just under the radiator. There is a hole in the skid shield. Press on the end of it with a flat screw driver and then insert a small pin to lock it in the open position. This is necessary as the external cooler is only open to the ATF fluid cooling circuit when the fluid is at higher temperatures. It is necessary to make sure the external cooler is also full of fluid when correctly refilling the transmission as per Toyota Tech Info procedures.
Start the vehicle and put it in Drive with your foot on the brake for 10 seconds, then reverse for 10 seconds to fill the circuits with fluid. Then back in park. Then fill the transmission further until it spills out the straw again with the vehicle running still. Then with your scantool or Scangauge II with 4.42 software or higher and X-Gauge code for the Transmission Pan temperature. Wait until the fluid reaches 104F and reinstall the drain plug. Your transmission is now full to the correct level. Do not exceed 113F before putting the plug back in the bottom of the transmission or it will be under full. This temperature changes rather quickly in hot weather so be quick about it.
This is has to be done with the body of the vehicle level off the ground so you will need jack stands for the rear and front of the vehicle to do it properly. It's also best to do it when the vehicle is cold because it will quickly heat the transmission fluid back up over the 104F really quickly thanks to the coolant to ATF heat exchanger.
Simply removing fluid from the pan and pouring the exact same amount of fluid back into the transmission can have undesired consequences due to fluid expansion rates differing from Toyota WS official fluid and some other brand that meets this specification which is why it's best to fill and check using the procedure above. Toyota advises always using this method for refilling the transmission anyway.
If anyone has this transmission and has questions about this change procedure feel free to send me a PM.
I will tell you after having done this today on my UA80F transmission the Toyota WS fluid leaves a lot to be desired in terms of shift quality and I would highly advise using some other brand that meets the WS fluid specification. I chose Amsoil Fuel Efficient Vehicle formula which is meant to replace WS fluid, because I'm a fan of their transmission oils and have used them in the past with excellent results but there may be other quality manufacturers out there just as good.
Sorry I didn't think to take pictures of the process but when I drain/refill again I will take pictures.