Thoughts on LS430 rough shifting and A761e transmission
03-15-19, 04:31 PM
#46
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Thread Starter
Update:
ECM is re-installed in ls430. SIA provided lifetime warranty. The invoice stated: Rebuilt transmission circuitry and highly recommended reprogramming smth (I cant read what exactly).
Day 1. Harsh shifting is completely gone. The acceleration is incredibly smooth. I was trying to catch shifting, but after 15 min drive I am no longer can say that I notice it.
I would never get the result like this if I turn off negative battery cable for more than 20 min, or do any other reset using Techstream. As for me, the problem is solved.
However, I will go ahead and submit observation reports twice a week just to ensure the fix is permanent.
ECM is re-installed in ls430. SIA provided lifetime warranty. The invoice stated: Rebuilt transmission circuitry and highly recommended reprogramming smth (I cant read what exactly).
Day 1. Harsh shifting is completely gone. The acceleration is incredibly smooth. I was trying to catch shifting, but after 15 min drive I am no longer can say that I notice it.
I would never get the result like this if I turn off negative battery cable for more than 20 min, or do any other reset using Techstream. As for me, the problem is solved.
However, I will go ahead and submit observation reports twice a week just to ensure the fix is permanent.
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03-16-19, 12:40 AM
#47
Yes I know it’s 3 am. But I just finished installing the ECM, filling the car up with coolant, torquing the newly powdercoated wheels to spec (pics to come) and filling & bleeding the coolant, which I never got the chance to do after doing my timing belt.
But wow, what a difference. I laughed out loud as soon as I took off down the road in the car. It never has shifted so smoothly, especially the 1-2 shift, which used to be pretty evident but now is completely seamless. No harsh downshifts, and most importantly, no harsh upshift from 5-6 which bothered me the most. Also, when I floor it, the car doesn’t hunt for a gear like it used to. It immediately downshifts and takes off, no hesitation or delay. Frankly, the car now shifts as smooth/smoother than my 98 LS400 which is damn high praise. The LS430 has always been in a different league when it comes to stillness at idle in Drive, which my 400 cannot even touch, no change there.
Overall, if my 430 keeps these shift parameters it will be the best $115 I’ve spent on any car, ever. I will post updates if anything changes.
But wow, what a difference. I laughed out loud as soon as I took off down the road in the car. It never has shifted so smoothly, especially the 1-2 shift, which used to be pretty evident but now is completely seamless. No harsh downshifts, and most importantly, no harsh upshift from 5-6 which bothered me the most. Also, when I floor it, the car doesn’t hunt for a gear like it used to. It immediately downshifts and takes off, no hesitation or delay. Frankly, the car now shifts as smooth/smoother than my 98 LS400 which is damn high praise. The LS430 has always been in a different league when it comes to stillness at idle in Drive, which my 400 cannot even touch, no change there.
Overall, if my 430 keeps these shift parameters it will be the best $115 I’ve spent on any car, ever. I will post updates if anything changes.
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JBrady (03-19-19)
03-16-19, 07:38 AM
#48
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Thread Starter
Peacebay, I am glad you are also enjoying your ride after the fix. Definitely the investment into SIA services paid back with the superior comfort restored to OEM standards... Apparently now I know how Ls430 rides when it comes off the factory 
). Lately I ve been using a lot of LyFT, and oh man... I don’t see changing my car to any new ones for probably another 10 years maybe... So many critical thoughts about other new cars that I wanna express, but rather not, related to suspension, noise, shifting (lol), interior space, and overall comfort. Just nothing stands close to ls430 value...
Looking forward to seeing you car pictures with new wheels. Also, I completely forgot to mention, because I have new custom exhaust and thanks to proper shifting, I am finally getting really really deep quality muffler sound in all gear range, which is extremely pleasant to ears (nothing crazy loud). Especially, now that second gear is engaged at the right time, there are no longer acoustic “interruptions” in acceleration. So happy about that lol
). Lately I ve been using a lot of LyFT, and oh man... I don’t see changing my car to any new ones for probably another 10 years maybe... So many critical thoughts about other new cars that I wanna express, but rather not, related to suspension, noise, shifting (lol), interior space, and overall comfort. Just nothing stands close to ls430 value... Looking forward to seeing you car pictures with new wheels. Also, I completely forgot to mention, because I have new custom exhaust and thanks to proper shifting, I am finally getting really really deep quality muffler sound in all gear range, which is extremely pleasant to ears (nothing crazy loud). Especially, now that second gear is engaged at the right time, there are no longer acoustic “interruptions” in acceleration. So happy about that lol
03-16-19, 09:19 AM
#49
Moderator
Simply check the ripple voltage at the Vcc line of the ECU and will know the answer.
03-17-19, 04:08 PM
#50
Moderator
My '05 has had somewhat rough 5-6 upshifts, seems like it hunts occasionally, and a yr ago had the violent 2-1 downshift problem. Saw somewhere on this board the following process to reset the trans:
a. insert key
b. turn key to on, no start
c. press gas pedal to floor
d. hold pedal to floor 5 seconds, key to off position, then release gas pedal
e. wait 2 minutes
f. remove key.
I tried it and was stunned at the improvement. Suddenly the trans shifts ultra smooth, no notchiness at all in any gear, the 2-1 downshift tug is gone. Quite surprised but very pleased.
As someone else commented I guess this means the trans adjusts itself over time based on driving behavior. If this is true, I'd really like to understand the logic of the adjustments...meaning, driving behavior xxxx results in specific adjustments yyyy. Would be very interesting to understand what Toyota engineered here.
a. insert key
b. turn key to on, no start
c. press gas pedal to floor
d. hold pedal to floor 5 seconds, key to off position, then release gas pedal
e. wait 2 minutes
f. remove key.
I tried it and was stunned at the improvement. Suddenly the trans shifts ultra smooth, no notchiness at all in any gear, the 2-1 downshift tug is gone. Quite surprised but very pleased.
As someone else commented I guess this means the trans adjusts itself over time based on driving behavior. If this is true, I'd really like to understand the logic of the adjustments...meaning, driving behavior xxxx results in specific adjustments yyyy. Would be very interesting to understand what Toyota engineered here.
Hey guys THIS WORKS !!! Quite a noticeable difference, thanks again toddmorr
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JBrady (03-19-19)
03-19-19, 09:20 AM
#51
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Thread Starter
Day 5. Transmission is extremely smooth and pleasant for driving experience. No need for additional adjustments or memory reset so far. Looking forward to enter the second week of testing to see if any changes will be observed.
03-19-19, 09:32 AM
#52
Advanced
Thread Starter
. I actually tried the procedure after the ECM being repaired and unfortunately couldn't observe any difference lol. I wonder if my transmission now shift smoothly disregarding any memory-preset.But could you please describe what was different before the reset?
03-19-19, 01:56 PM
#53
Moderator
Good for you . I actually tried the procedure after the ECM being repaired and unfortunately couldn't observe any difference lol. I wonder if my transmission now shift smoothly disregarding any memory-preset.
But could you please describe what was different before the reset?
. I actually tried the procedure after the ECM being repaired and unfortunately couldn't observe any difference lol. I wonder if my transmission now shift smoothly disregarding any memory-preset.But could you please describe what was different before the reset?
03-19-19, 02:36 PM
#54
I've never had an issue with highway driving but the car always felt a bit loose or floaty in slower parking lot driving. I'm struggling to find the right word and still not sure if loose or floaty is correct. There was a very slight disconnect in pedal feel I always assumed was inherent to drive by wire throttle bodies. It was never enough to make me think anything was wrong but just enough to plant a little doubt in the back of your mind. Fast forward, no pun intended, to post the above procedure and I feel connected when driving slow and all of a sudden I have throttle response! What's interesting is I was considering replacing the fuel pulsation dampers to remedy the lack of throttle response...
03-20-19, 01:58 PM
#55
Update: even though my car hasn't done the harsh 2-1 downshift, it's back to the almost the exact same stuff. The harsh 5-6 upshift is back in full force. So frustrating, almost makes me want to sell the car at this point.
03-20-19, 02:06 PM
#56
Lexus Champion
Hmm. Is this just casual 5-6 upshifting or heavy throttle at high speeds?
The 5-6 isn't as smooth as the others on heavy throttle at highway speeds. I wouldn't call it harsh either, just more abrupt than usual.
If this is what you're experiencing, it's normal. Or, at least I've noticed it and have never had one transmission issue other than not doing the TSB for the 2-1 downshift (bc I don't care and don't live in an area where it presents itself very often at all). They're solid transmissions, I can't recall anyone ever having one fail on here.
Sorry for your problems, though. Hope you get it sorted out.
03-20-19, 02:14 PM
#57
It’s only ever when I’m cruising with my foot *barely* on the throttle, accelerating slowly from let’s say 40-50 mph. At 45, it’ll just throw itself into 6th so abrupty that it’s very noticeable. And at this point I’m so hyper aware of this I might be making it into a bigger problem in my head than it really is, but there is no mistaking that final upshift, believe me.
At moderate throttle the car shifts wonderfully
At moderate throttle the car shifts wonderfully
03-20-19, 02:18 PM
#58
Lexus Champion
It’s only ever when I’m cruising with my foot *barely* on the throttle, accelerating slowly from let’s say 40-50 mph. At 45, it’ll just throw itself into 6th so abrupty that it’s very noticeable. And at this point I’m so hyper aware of this I might be making it into a bigger problem in my head than it really is, but there is no mistaking that final upshift, believe me.
At moderate throttle the car shifts wonderfully
At moderate throttle the car shifts wonderfully
What year and mileage? Ever had the fluid changed?
03-20-19, 02:23 PM
#59
05, 85,000 miles. I’ve had the fluid drained and filled two seperate times by my Lexus dealer and once by myself.
03-20-19, 02:28 PM
#60
Lexus Champion
Have you checked your motor mounts?