Went to check my transmission fluid but don't see any dipstick. Is the transmission in my 06 SC 430 a 'sealed' transmission? I was told by a Japanese shop if the fluid looks good don't change it. What's the skinny on when and if to change tranny fluid? (and what does a tranny service typically cost?)

 

SC430 2006-2010 Transmission fluid change procedure

 

1. Yes
2. True
3. Transmission fluid should be inspected at intervals of 30,000 miles according to the Lexus maintenance schedule for a 2006 vehicle. The inspection determined if a change is necessary. Toyota/Lexus WS sealed transmissions are typically good for 100k between fluid changes UNDER NORMAL driving conditions. Your mileage will vary.
Cost? will vary due to many variables, a fair “dealer” price $100-150

BTW in addition to the PDF reposted above, here is a link to a YouTube video describing a transmission fluid change on a Toyota/Lexus WS (World Standard) sealed transmission:

 

This is not to contradict VVTiBob.

In the video, I'm surprised that that the pan is not dropped, there is no transmission filter or magnet discussed and the amount of fluid is so small. What is the real capacity of the transmission including the torque converter?

During that decade, at least, the reason many manufacturers recommend such a long fluid interval change is to keep the cost of ownership down. COO directly affects JD Powers ratings. Most original owners/lessors will never see 100k miles.

My experience is based on too many years of running MB that had a similar change interval in those decades. I can tap a fluids expert from a major company like a Shell, etc. For example, my "fluid" friend recommends 40k miles as a fluid change and transmission service on older 5 speed and newer 7 speed transmissions. MBUSA says 70k miles in one instance and "inspection", 100k, or never "lifetime fluid." BTW many of these transmissions have no dipstick.

In the rest of the world the change interval is 40k miles.

Thus we have ours done fully at 40k miles on all our cars. For a dealer price of $100-150 on the Lexus that is cheap insurance. But I have misgivings that the service in the video is a complete service.