I have a 2007 RX350 with around 265,000 miles.
I had the car serviced including a minor transmission service about 10,000 miles ago at a Lexus dealer. A couple of days ago, the clutch started slipping really bad, so I took it to a local mechanic and he said the transmission had virtually no fluid in it, what existed with black and gunky. They tried flushing it and refilling it to see if the transmission could be saved, but the replacement fluid turned black, too. My only option to save the car is to replace the transmission. The mechanic said Lexus considers the transmission fluid permanent so they generally just drain some and add some during a service, so it just gets dirtier and dirtier. He said if I had been maintaining the transmission properly, it wouldn't have failed. But I have always taken it to the dealer for service on a regular basis!
My question is, if I just had the car serviced 10,000 miles ago, wouldn't they have noticed how bad the fluid was? I just don't understand how I could have gotten to full fluid, even dirty, to almost no fluid in 10,000 miles.
Thanks --