Hesitation problem at various speeds (TSB info post #159)
#1531
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On another note, does anyone else notice when sitting in the back row that you feel sensitive to the acceleration/braking? I sat in the backseat while my dad drove and felt like I was getting pushed hard when accelerating and pulled during brakes. He doesn't have a heavy foot either. It just doesn't feel like a smooth ride sitting in the back.
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#1532
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My wife would agree with Mike. Passengers feel acceleration and braking more than the driver because the driver has a steering wheel to hold onto. Ray A.
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jollick (01-04-21)
#1533
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Hi,
I bought a new 2018 Rx350 last week, the car is sluggish in acceleration after a stop sign/ red light, when i push the accelerator i can hear sort of vibration below my seat and across the car. it seems like its either missing transmission or changing gears, it all goes away when i take my foot off the accelerator pedal and push it again.This happened a few times, specially when i am getting on a highway/freeway. Overall it runs smooth and a nice ride.
My question: is this a common problem in new car and will it go away once i put more km on it or do i get it checked out at dealership.
Thanks in advance for all the help.
Note: If this topic has already been discussed in a previous thread please let me know, I will remove this thread and post my query in other one.
I bought a new 2018 Rx350 last week, the car is sluggish in acceleration after a stop sign/ red light, when i push the accelerator i can hear sort of vibration below my seat and across the car. it seems like its either missing transmission or changing gears, it all goes away when i take my foot off the accelerator pedal and push it again.This happened a few times, specially when i am getting on a highway/freeway. Overall it runs smooth and a nice ride.
My question: is this a common problem in new car and will it go away once i put more km on it or do i get it checked out at dealership.
Thanks in advance for all the help.
Note: If this topic has already been discussed in a previous thread please let me know, I will remove this thread and post my query in other one.
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armandtoe (02-18-21)
#1535
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Recently purchased a used 2017 rx350. It’s very jumpy a low speed especially going from 20 to 30 mph. The trans can’t make up its mind. It’s really noticeable when it’s cold. (not operating temp) It almost seems like a fuel issue. Is it an issue or the result of having an 8 speed?
#1536
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Recently purchased a used 2017 rx350. It’s very jumpy a low speed especially going from 20 to 30 mph. The trans can’t make up its mind. It’s really noticeable when it’s cold. (not operating temp) It almost seems like a fuel issue. Is it an issue or the result of having an 8 speed?
#1537
Driver School Candidate
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Recently purchased a used 2017 rx350. It’s very jumpy a low speed especially going from 20 to 30 mph. The trans can’t make up its mind. It’s really noticeable when it’s cold. (not operating temp) It almost seems like a fuel issue. Is it an issue or the result of having an 8 speed?
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Andrew2020 (04-11-21)
#1538
Driver School Candidate
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I've been having the same issue on my 2016 RX350. I've got TSB L-SB-0032-19 applied but it didn't make any significant differences in the shifting. 'Transmission can't make up its mind' is exactly how I'd describe it as well. It really takes the pleasure out of driving this vehicle especially in slightly mountainous areas. Using premium fuel seem to make it better (most likely because of better low-end torque), so does using Red Line additive. At this point, I have given up on this issue and I'm trying to suck it up.
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Rxyen (04-11-21)
#1540
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#1541
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If the purpose of the faulty shifting is for fuel mileage, it seems that Lexus shot itself in the foot. My most recent 2020 RX 350 loaner was an absolute piece of garbage. I drove it home in the rain in the Texas Hill Country & that transmission was all over the place & my mpg was just over 20 mpg. I told the dealer that it shifts all over the place (jumps up to high gear too fast, then shifts down & surges). They said it was normal. That is not normal transmission behavior. That experience made me appreciate my CVT on my 450h!
#1542
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If the purpose of the faulty shifting is for fuel mileage, it seems that Lexus shot itself in the foot. My most recent 2020 RX 350 loaner was an absolute piece of garbage. I drove it home in the rain in the Texas Hill Country & that transmission was all over the place & my mpg was just over 20 mpg. I told the dealer that it shifts all over the place (jumps up to high gear too fast, then shifts down & surges). They said it was normal. That is not normal transmission behavior. That experience made me appreciate my CVT on my 450h!
Of course it would be ideal if the car would be smooth in all conditions when driven by different drivers. I don't know what Lexus were thinking but going by the fact fuel consumption is a big consideration and this thing isn't good on fuel at any time they decided to go the fuel economy route. It's a Lexus, a largish Lexus which traditionally more matured people go for, people who don't drive hard, people who give it gentle throttle openings and under those conditions it works well as is in Normal Mode. Want more go throw it in Sports and it works better if you're the kind of person that likes more pace, wider throttle openings Sports Mode is great.
As I said there is a TSB for it, for people who don't like the mapping and this changes it to be more like Sports Mode when in Normal Mode. Yes I know YOUR car may not have been better but seems plenty on here did have a better experience with the TSB applied.
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rxtimes2 (04-12-21)
#1543
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By the way I get around 21/22 in town and 30 on the freeway.
#1544
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My Fuelly app is averaging between 24-26 mpg in 75% Highway & 25% City driving in my RX 450h. I think the new Tundra the twin turbo 3.5 V-6 will be interesting. Small Toyota vehicles seem to get great mpgs, but bigger V-6 & V-8 models can be pretty awful & WAY worse than their competitors. I’m curious if the 8 speed tranny in the 350 is used across the board now. Anybody know?
#1545
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EDIT: Contrary to Wiki, my 2015 RX had a six speed transmission. I believe this 8-speed was new for Gen 4, starting in 2016, not 2013.
Last edited by dibl; 04-12-21 at 09:54 AM.