Lexus Unable To Diagnose Tranny Problem

kikikikopa · April 4, 2006

Here's one for the books because according to Lexus Customer Satisfaction they've not had this happen before. Just my luck!

I've got a 2000 LS with 63K miles. The problem is harsh engaging of the transmission between 1st & 2nd gears and only while coasting with no acceleration. It will happen often in stop and go traffic on the Interstate when everything is at a crawl. It's an intermittant problem but when it happens it's severe and can only be described as slamming into gear with a loud clunk. I had to take the service tech on a test drive to duplicate the problem because they could not on their test drive.

Lexus has had the car for four weeks now and supposedly have ruled out every other possible cause of the problem before they finally decided to replace the transmission. Unfortunately, this did not solve the problem although the service advisor still wanted me to pick up the car saying that even though the problem is still there, it's not as bad as it was. Not as bad as it was??? It was an intermittent problem to begin with!

I contacted the service manager and he agreed that the problem was not fixed and that they would continue to search for the cause of the problem. "Put our nose to the grindstone" is the exact phrase that he used.

So here it is, four weeks since they've had my car and it's still not fixed. It is under the powertrain warranty which is good but now I'm wondering what would be the options if they ultimately can not fix the problem?

Will Lexus corporate buy the car back? Will they offer me a replacement LS?

Anyone with a story to share about a similar type experience would be welcome. I'm beginning to lose faith in their ability to solve this problem and don't know what to expect. I do know that I want my LS back. The loaner I have is the RX300 which is nice but in a different class alltogether.

SKperformance · April 4, 2006

Mine does the same thing . It has nothing to do with the tranny but a poor excuse for a computer engineers salary. Basically the tranny is in neutral and does not know which gear to select by having to maps it uses.

All Toyota and some other cars with drive by wire throttles have the problem . Some cars more than others . It also comes down to how you drive the car. To almost completely remove the problem use the tranny in PWR mode and also stay out of D and use 4 instead. Then the idle-to-coast-to-accelerate problem will no longer be present as the TC is not being engaged and the ecu does not have to think about it.

monarch · April 4, 2006

kikikikopa, the upshift from 1st to 2nd while coasting should occur at very low speeds ( 5-15 mph) . Is this the case with your car? And are you saying the harsh engagement occurs only when your foot is fully off the accelerator?

kikikikopa · April 5, 2006

Just got off the phone with the Lexus dealer and they've determined that this is a normal condition under the correct circumstances. The problem I hade was magnified by a loud clunk sound which they associated with the prop shaft needing adjusting so that aspect of it has been eliminated. This is not something that they were aware of since they did install a new transmission in the car thinking that was the cause of the problem That tells me that this issue is not full recognized by Lexus otherwise they would not have resorted to replacing the transmission. I'm picking the car up tomorrow and will update this thread on what the car drives like after all the work that's been done to it. My thanks to the folks that took the time to comment on this issue which gave me a better understanding of the problem.