View Poll Results: Is this normal?
Yup! And the car will take it just fine for years!
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32
91.43%
Ehhh no! Get another dealer to check it out.
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2
5.71%
Meh, no clue
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1
2.86%
Voters: 35. You may not vote on this poll
Transmission low speed downshift stutter
#31
Intermediate
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Yes I am pretty sure I experienced this as well. Since adding my mid pipe and new exhaust, the car performs differently and these things you mention Arentz are gone. As it was for me anyway, they were subtle to begin with. The new things that are happening is the shifts are smoother, yet more pronounced. I get this awesome subtle back draw from the engine as it shifts from 5th gear where the issue you mentioned once occurred. I am of the opinion, a lot of tangibles effect the ECU for this car given it's parts and pieces are from various models. At the end of the day they married alot of things together and these subtleties have some effects that we scratch our heads with. I guess what I am saying, I never expected the exhaust modification to have a profound effect on shifting subtleties like it did. The overall mod was a drastic improvement to alot of areas to the car, which I could explain better in person than writing out. The only thing I miss previous mod exhaust is having a stock quiet option. When the valves are closed, it is quiet but not like it was stock. Not trying to make your question Arentz about exhaust, just pointing out the issue you mentioned went away or should I say became very smooth with my exhaust change.
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MYIS500 (12-13-23)
#32
Lexus Connoisseur
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btw I’ve search the forum before and read this article https://motorfrontier.com/aisin-long...sion-analysis/ , so I knew the aa81e is clunky, but this felt straight up broken.
Anyone else experiencing this?
With that said, have you been experiencing this before or after you modified your wheels/tires and etc.
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Oloung1 (05-15-24)
#33
drives cars
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AA80E with Lock up torque converter is the same trans in the IS F, RC F, GS F and LS 460 SPORT/F SPORT. First appeared in the 4th Gen LS in 2007-2017, 3rd Gen GS 460 (2008-2011)…not to be confused with AA81E only used with the 2GR applications.
With that said, have you been experiencing this before or after you modified your wheels/tires and etc.
With that said, have you been experiencing this before or after you modified your wheels/tires and etc.
#34
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So, I've modified my driving habits a bit since getting IS 500. I typically start braking pretty early, but that seems to set of the clunk rather reliably. What I been noticing is that the car likes more brake pressure. Hence, lately I've been braking a bit later and harder than I normally would prior. Nothing too crazy, maybe 10-20% difference. That seems to work a lot better. Still get an odd lurch once in a while, but nowhere near what I used to get in the past.
This reminds of the first gen DSG (dual clutch gearbox) I got in my Mk5 GTI. For a while I was driving on the defective mechatronics unit that they recalled eventually and gave everyone affected 10 year DSG warranties. One of its issues was this exact behavior. It would slam into gear while slowing down to a stop.
Ugh... Now thanks to IS 500, I can add PTSD from resurfaced old trauma to my list of issues.
This reminds of the first gen DSG (dual clutch gearbox) I got in my Mk5 GTI. For a while I was driving on the defective mechatronics unit that they recalled eventually and gave everyone affected 10 year DSG warranties. One of its issues was this exact behavior. It would slam into gear while slowing down to a stop.
Ugh... Now thanks to IS 500, I can add PTSD from resurfaced old trauma to my list of issues.
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Last edited by DeepBlue99; 12-17-23 at 03:31 PM.
#35
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got my transmission replaced because of this exact same issue it's been going on, unfortunately it made no difference so the dealer had to convince me that it's normal, clearly it is NOT!!! today i went to test drive another is500 just to compare and that IS500 transmission was buttery smooth, i will schedule an appointment and take it back, i dont care if they gonna have to put another 10 new transmissions to get this fix but i am not going to deal with it, it is stopping me from loving this car, hste to drive it around my neighborhood, it should not this be this way
#36
Advanced
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Is your issue the downshift when coming to a stop? Particularly it shifts from 5th to 3rd. Skipping 4th seems to make a harsh jerk. Seems like the trans is programmed to make the skip. It’s much more pronounced when cold but is present when warmed as well.
#37
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got my transmission replaced because of this exact same issue it's been going on, unfortunately it made no difference so the dealer had to convince me that it's normal, clearly it is NOT!!! today i went to test drive another is500 just to compare and that IS500 transmission was buttery smooth, i will schedule an appointment and take it back, i dont care if they gonna have to put another 10 new transmissions to get this fix but i am not going to deal with it, it is stopping me from loving this car, hste to drive it around my neighborhood, it should not this be this way
#38
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yes!!! What i also noticed, the tach doesnt align with the actual gearing, because i feel the downshift but the tach remain showing i am on the 5th gear for a second or two then it drops to 3rd.
#39
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I'm pretty sure that the TCM thinks you're going to hit the gas again so it hangs on 3rd. When I drove my car like a Camry for the first few thousand miles it started shifting like a Camry (also fully warmed up). I've been driving spiritedly lately, and when I do, it likes to hold that third gear when coming to a stop. But if I start acting like I'm in the Camry again it seems to adjust quicker. Just my observation, could be wrong.
#40
drives cars
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This brings me to the reason for the clunk, at least in my experience - I think it is the torque converter unlocking while we decelerate. This is just a hypothesis, but... read on, if you will. The torque converter locks above certain speeds in 2nd gear or above, and, conversely, it unlocks at certain low speeds. I observe the clunking noise/feeling when I am in manual mode if I keep the car in second gear if I decelerate gradually (i.e., just foot off the gas or gentle braking) in addition to while decelerating in Normal mode with the gear selector in Drive. I can also feel it locking up in manual mode - happens in second gear at about 23 MPH. It feels like the car hesitates for a second when it hits this speed unless I give it a lot of throttle. Regardless of how warmed-up the car is, it will always happen. Maybe the reason I only notice it in second gear in manual mode is just due to how gearing works. Second gear has a higher ratio than 3rd, 4th, etc., so any changes in torque to it will be more easily felt than those higher gears. And, as mentioned before, the torque converter only locks in second gear or higher, so I wouldn't have felt it in first gear. This may also explain why downshifting into first gear can be quite rough at low speeds. If you perform it at higher speeds, i.e., above 25 MPH or so, the car performs a rev-matched downshift into first, though there's still a bit of roughness to it. Either way, I don't experience any other weirdness with the transmission outside of these low-speed deceleration scenarios, which is exactly where we expect the torque converter locking and unlocking to be done.
By the way, I will say that I noticed some similar behaviors in my prior car, my IS 350, though not as pronounced as in the IS 500.
#43
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i will tell you why, it only happens if you reached the 6th gear and then start slowing down, if you slow down right after after 5th gear it’s not going to do that, and sport plus usually keeps in low gears.
#44
Driver School Candidate
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