Hesitation problem at various speeds (TSB info post #159)
#1397
#1399
#1400
For Canada it was "L-TCI-5285" which is equivalent of "L-SB-0032-19" in US. TSB was dated July 2019.
So you are saying that there is newer revision of "L-SB-0032-19" which was released on September 2019?
Can you post where can I get a copy of it? (with the rev)
Here is the one I got back in August 2019
#1401
The module is by PowerTune but here is an update. They say the unit goes into learning mode for the first few weeks and I think a little bit of the hesitation MAY be back after it was totally gone when I first plugged it in. I will test it again today and report back. If it does come back, I will reset it, remove it and put it back in and see what happens.
Stay tuned.
Stay tuned.
#1402
The module is by PowerTune but here is an update. They say the unit goes into learning mode for the first few weeks and I think a little bit of the hesitation MAY be back after it was totally gone when I first plugged it in. I will test it again today and report back. If it does come back, I will reset it, remove it and put it back in and see what happens.
Stay tuned.
Stay tuned.
#1403
#1404
GSFRX350, that is very important information. I have done it in Canada in August 2019 and I am very disappointed with the result.
For Canada it was "L-TCI-5285" which is equivalent of "L-SB-0032-19" in US. TSB was dated July 2019.
So you are saying that there is newer revision of "L-SB-0032-19" which was released on September 2019?
Can you post where can I get a copy of it? (with the rev)
Here is the one I got back in August 2019
For Canada it was "L-TCI-5285" which is equivalent of "L-SB-0032-19" in US. TSB was dated July 2019.
So you are saying that there is newer revision of "L-SB-0032-19" which was released on September 2019?
Can you post where can I get a copy of it? (with the rev)
Here is the one I got back in August 2019
#1405
I had the TSB done back in May. On a road trip this week I started to notice occasional hard downshifts/surges on deceleration and more pronounced upshifting at high speeds -- particularly when going uphill. So while on the road trip I took the car to the Lexus dealership that sold me the car. A senior tech (18 years with Lexus) road with me for a 17-mile test drive. Unfortunately I couldn't reproduce the upshifting/uphill behavior, but I could reproduce the "surge." In his view that behavior wasn't abnormal. Let me be clear -- the tech wasn't trying to brush me off. He offered to keep the car and have a regional expert come in to take things further.
I asked him if the TSB was done correctly. He explained that it was. He also ran a complete diagnostic on the RX and showed me the results (all normal; no codes). The transmission was calibrated correctly.
The tech did ask me if the battery had been disconnected lately. I said no. He then mentioned that a disconnect will trigger a transmission relearn procedure. So I asked him to disconnect my battery to trigger a relearn. He did. I've driven ~10 miles since then and the transmission behavior is much improved.
One thing that's been troubling me is why the '17 RX shifts so differently than the 8-speed in my '20 ES. I thought that Lexus used the same Aisin 8-speed in all applications, but I was wrong:
'17 RX FWD: U881E
'17 RX AWD: U881F
'20 ES: UA80E
I asked him if the TSB was done correctly. He explained that it was. He also ran a complete diagnostic on the RX and showed me the results (all normal; no codes). The transmission was calibrated correctly.
The tech did ask me if the battery had been disconnected lately. I said no. He then mentioned that a disconnect will trigger a transmission relearn procedure. So I asked him to disconnect my battery to trigger a relearn. He did. I've driven ~10 miles since then and the transmission behavior is much improved.
One thing that's been troubling me is why the '17 RX shifts so differently than the 8-speed in my '20 ES. I thought that Lexus used the same Aisin 8-speed in all applications, but I was wrong:
'17 RX FWD: U881E
'17 RX AWD: U881F
'20 ES: UA80E
#1406
I had the TSB done back in May. On a road trip this week I started to notice occasional hard downshifts/surges on deceleration and more pronounced upshifting at high speeds -- particularly when going uphill. So while on the road trip I took the car to the Lexus dealership that sold me the car. A senior tech (18 years with Lexus) road with me for a 17-mile test drive. Unfortunately I couldn't reproduce the upshifting/uphill behavior, but I could reproduce the "surge." In his view that behavior wasn't abnormal. Let me be clear -- the tech wasn't trying to brush me off. He offered to keep the car and have a regional expert come in to take things further.
I asked him if the TSB was done correctly. He explained that it was. He also ran a complete diagnostic on the RX and showed me the results (all normal; no codes). The transmission was calibrated correctly.
The tech did ask me if the battery had been disconnected lately. I said no. He then mentioned that a disconnect will trigger a transmission relearn procedure. So I asked him to disconnect my battery to trigger a relearn. He did. I've driven ~10 miles since then and the transmission behavior is much improved.
One thing that's been troubling me is why the '17 RX shifts so differently than the 8-speed in my '20 ES. I thought that Lexus used the same Aisin 8-speed in all applications, but I was wrong:
'17 RX FWD: U881E
'17 RX AWD: U881F
'20 ES: UA80E
I asked him if the TSB was done correctly. He explained that it was. He also ran a complete diagnostic on the RX and showed me the results (all normal; no codes). The transmission was calibrated correctly.
The tech did ask me if the battery had been disconnected lately. I said no. He then mentioned that a disconnect will trigger a transmission relearn procedure. So I asked him to disconnect my battery to trigger a relearn. He did. I've driven ~10 miles since then and the transmission behavior is much improved.
One thing that's been troubling me is why the '17 RX shifts so differently than the 8-speed in my '20 ES. I thought that Lexus used the same Aisin 8-speed in all applications, but I was wrong:
'17 RX FWD: U881E
'17 RX AWD: U881F
'20 ES: UA80E
The hard downshifts are normal in the RX, I'm in Australia with a Jap built car and it does it, only occasionally and quite random. I regularly go on a 1,400 km round trip to visit family, same road everytime and just out of the blue a hard downshift will happen. It's so random and infrequent that I haven't bothered having it looked at.
Yes disconnecting the battery will reset the transmission, it learns your driving style and adapts the gear changes to your style. Do you have more than one person regularly driving your car? If so and one person is a hard driver (fast, large throttle openings) and the other is gentle (slow, feathering the throttle) it will screw up the learning process and the transmission may struggle to suit both of you.
#1407
I'm the only driver!
I agree that it seems that the transmission is programmed to reach the highest gear ASAP (in normal mode).
The hard downshifts are definitely intermittent. I guess what surprises me are the vast differences in shifting between my RX and ES. The ES shifts like butter. But you're right -- they're different vehicles!
I agree that it seems that the transmission is programmed to reach the highest gear ASAP (in normal mode).
The hard downshifts are definitely intermittent. I guess what surprises me are the vast differences in shifting between my RX and ES. The ES shifts like butter. But you're right -- they're different vehicles!
#1408
Driver School Candidate
Join Date: Jul 2020
Location: FL
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I'm new to this forum. I have a 2017 RX350 with the same downshift clunk problem when I slow down for a light. It also jerks when I accelerate sometimes at highway speeds. The dealer tells me there are no service bulletins to fix this. Does anyone have further information on this issue?
#1409
I'm new to this forum. I have a 2017 RX350 with the same downshift clunk problem when I slow down for a light. It also jerks when I accelerate sometimes at highway speeds. The dealer tells me there are no service bulletins to fix this. Does anyone have further information on this issue?
The TSB number is upthread. Once it's done make sure that the tech disconnects the battery to reset everything.
#1410
Driver
For those in Canada is the dealer applying L-SB-0032-19_Rev for you?
I contacted my local dealer in the Toronto area and he told me L-SB-0032-19_Rev is for US vehicles only. I'm dropping off my car later this week so they can "hook it up to the computer to see if anything can be applied".
I contacted my local dealer in the Toronto area and he told me L-SB-0032-19_Rev is for US vehicles only. I'm dropping off my car later this week so they can "hook it up to the computer to see if anything can be applied".