I didn't decide not to change the fluid because it's difficult to do, I decided not to do it because doing so would void my warranty...
Originally Posted By: nthach
The task of draining the fluid isn't hard, there's a "check" plug with a 6mm that covers the fluid level standpipe which also doubles as the fluid drain - the same 6mm hex/Allen will remove that as well. There's a 24mm fill plug on the wheel side of the tranny. Make sure the standpipe is reinstalled. There are two schools of thought about the fluid level check - both need the tranny fluid between 100-113*F. The first way is to pull the 6mm check plug while the car is running and level and either let it drain to a trickle or add fluid until it trickles out. The second way is to pull a vacuum on the tranny case and install the official "level check device(https://www.carmd.com/Tsb/Download/98051/T-SB-0036-13)" to the oil pan and see where the level lands on it. There's a few threads of the DIY fluid change, your Sienna's tranny is quite similar: http://www.toyotanation.com/forum/104-ca...0-camry-v6.html https://www.clublexus.com/forums/es-5th-...eplacement.html
Originally Posted By: doitmyself
It does have a 60,000 mile tranny fluid change interval for vehicles operated under "special conditions". Many of these transmissions are only "sealed" by a removable drain bolt, but I'm not up on the Toyota products.
Originally Posted By: grampi
My wife's new (well, new to us) 2015 Sienna has a sealed lifetime tranny...I'm not doing anything with it...the vehicle came with a lifetime warranty and breaking open the tranny would void the warranty...