My transmission went out at 75,000 miles without warning. Transmission would not engage when put into reverse. When I put into neutral to push from my garage, the transmission was "locked up" and vehicle would not move. Fortunately, I purchased an extended warranty with the car so the replacement cost was covered.
Two weeks later the check engine light came on while on my way to emissions testing to renew my registration. The vehicle failed emissions testing. I returned to the dealer and was told that I failed the emissions test because of a faulty value in the transmission that is a part of the emission control system. The dealer informed me that they would again have to replace the transmission because it is the policy of Lexus to replace not repair the transmissions. Again, this was covered under my extended warranty.
It is now about 6 weeks later and the check engine light is on again. I was due for service anyway so I took the car in to the dealer today 8/14/06 and requested they service the car and resolve the check engine light issue. I have 88,000 miles on the vehicle currently and the service adviser suggested that they should do the 90,000 mile service. I agreed.
I received a call from my service adviser stating that I need to have the timing belt replaced ($1,500.) and new spark plugs ($500.). I was shocked that spark plugs could cost $500 and asked why so expensive? He explained that in 1999 Lexus used both high mileage and low mileage spark plugs on the RX300 and mine has the low mileage plugs. He told me the high mileage plugs are more expensive and that the manifold must be removed to change the spark plugs resulting higher labor charges. My response was that Lexus should replace the plugs at their expense since they should have installed high mileage plugs in the first place. Needless to say, the advisor did not agree, said "it is what it is" and told me I would have to pay for the new plugs.
The timing belt is a potential problem that can be much worse if it actually goes out during operation. I have owned Mercedes that have required timing belt/chain replacements for about the same expense.
I have really enjoyed my RX300 up to the time the transmission started failing. I have had friends who have owned SC300's, GS400 etc and driven them for 200,000 plus miles with great performance, reliability and reasonable maintenance and replacement costs. I had hoped to keep my RX300 that long, but I am having serious second thoughts because of all of these problems - both my own and those I'm hearing and reading about.
I am concerned about the long-term viability of my RX300 and wonder if I should get rid of it while I can rather than wait until it leaves me stranded somewhere and becomes worthless or worse yet a money pit.
Can anyone relate long-term, high mileage experiences with the RX300 that are similar to the good feedback I've heard on other Lexus models?