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I find it hard to believe but I have suddenly started to feel sporatic jerky shifts especialy from 1-2 and 2-3 while under normal driving conditions in my automatic. Funny thing it was cool all the way up to 9500 miles? I find it hard to believe that this damn tranny is acting up after all this time. I think I will have to break down and the the ECU reflash and new Trac ECU. Anyone else having tranny shift problems after accumulating their mileage??

Rich.
 

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Talk to gabe, he has the same problem. He got the tranny flushed , he said it helped. I have 10,800 no problems here. Let us know what the dealer tells ya.
 

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I had the same problem like jiggafett said - dont remember exactly when it started but the dealer recommended a transmission flush at 15000 miles which I did. Made a huge difference - I recommend you do it - the transmission will be back to shifting very smooth, you wont even notice.
 

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I've went to my dealership several times complaining about this and they said it's a problem with the ECU. They said they have the same problem with the GS300/400's. They reset my ECU and took some data from the ECU to send it to Japan but they said the ECU would go back to the rough shifting within a couple weeks. They said there is no permanent fix at this time. I already had the ECU reflash and TRAC replacement too. My car started the rough shifting at around 7,000 miles and I'm at almost 9,000 now.

There was no mention of the tranny flushing though. Very interesting.
 

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I had the ECU/Trac updates and all seemed OK at first. Now the harsh engagement seems to be returning. Why can't Lexus design a decent throttle control?
 

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Uh Oh...and I thought it was my imagination the past three weeks or so (8700 miles now). Please, God...NOOOOOOOO....
 

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When I went in for the fix this morning, I got the "I know nothing about a TRAC fix." I busted out the TSIB # and he promptly called the supervisor, who knew exactly what I was talking about. I know I'm not the first one to get this done at the dealership, but it continues to amaze me how poorly Lexus keeps their service informed. They did, however, know all about the splashguard, so I can't completely write them off as uninformed.

Using an RX as a loaner today, and already looking forward to returning it.
ACK!
 

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I've got about 2,000 miles on the ECU/TRAC update and about 11k total miles on the car.

I have not noticed any unusual tranny shifts or acceleration problems w/my car. I'm in the process of doing my next service at 13k and may look at going to synth lube for the drivetrain.
 

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Got the ECU and TRAC fix done. Immediately noticed smoother shifts and the TRAC actually allowed some slight wheel spin without engaging. I think we have a winner.
 

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If after the TSB reflash is done and the transmission still shifts erratically, take it back to the dealer and tell them the ECU needs to be replaced. The TSB is really for a throttle response concern, not shifting. I test drove with the technician, and spoke with a Toyota Field Engineer (I'm a service manager at a Toyota delaer), They both reccomended replacing the TRAC ECU...and Bingo...Problem solved. I reccomed everyone do the same. You need to roadtestt so the teck knows exactly what your problem is. For some reason the Service writers assume you have the same problem that the TSB covers.
 

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If after the TSB reflash is done and the transmission still shifts erratically, take it back to the dealer and tell them the ECU needs to be replaced. The TSB is really for a throttle response concern, not shifting. I test drove with the technician, and spoke with a Toyota Field Engineer (I'm a service manager at a Toyota delaer), They both reccomended replacing the TRAC ECU...and Bingo...Problem solved. I reccomed everyone do the same. You need to roadtestt so the teck knows exactly what your problem is. For some reason the Service writers assume you have the same problem that the TSB covers.
 

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Originally posted by Risk3233:
I've got about 2,000 miles on the ECU/TRAC update and about 11k total miles on the car.

I have not noticed any unusual tranny shifts or acceleration problems w/my car. I'm in the process of doing my next service at 13k and may look at going to synth lube for the drivetrain.

Hey Risk3233!!

Please keep me informed on the synthetic lube on drivetrain.....Planning on synthetic transmission fluid also???? Now THAT I'm interested.....

Thanks in advance
 

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Originally posted by SilverLex:
Got the ECU and TRAC fix done. Immediately noticed smoother shifts and the TRAC actually allowed some slight wheel spin without engaging. I think we have a winner.

Hey SilverLex:

Sounds like your ECU has been reset too. Please keep us posted on the shifting. If what is300girl says is true, then you might have rough shifting back in a few weeks' time..... Hope that doesn't happen though.
 

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Originally posted by dude:

Hey Risk3233!!

Please keep me informed on the synthetic lube on drivetrain.....Planning on synthetic transmission fluid also???? Now THAT I'm interested.....

Thanks in advance
Sorry for jumping in.
I've replaced the differential oil with Mobil1 during the 15K service. Works great! I was also going to replace the ATF with the Mobil product, but my service manager advised me not to. Toyota has a special ATF, if you use a non Toyota ATF - the tranny will shift like crap. So I didn't.... regrets yet.
 
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