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Transmission problems with Lexus ES?

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Comments

  • hylynerhylyner Posts: 216
    Our new Avalon has some "hesitation", if you want to call it that. But not for long. At speeds of approx. 25 to 30 MPH, when I floor it (WOT), there is a momentary hesitation while it downshifts--maybe .5 seconds (or less perhaps, because I've never timed it)
    Then it really goes like stink--I bet it pulls a "G" or two. Accelleration is really exhilarating!!
    No problem whatsoever from my perspective. Sorry folks. I think it's great.
  • wwestwwest Posts: 10,706
    "....Personally I think not."

    Apparently Toyota disagrees with you. Somewhere I just read that the latest version of transaxle firmware is accomplishing downshifts in 0.5 seconds, "more than twice as fast as previously". That is in line with the shop manual stating that the shift from neutral to "drive" takes 1.2 seconds.

    What is the typical time it takes a stick shift driver to downshift from cruise to accelerate? That should be Toyota's transaxle downshift "target".

    "...something wrong..."

    Yes, IMMHO this whole episode begin with the earlier 4-speed transaxle versions being far too willing, too quick, to upshift. I have little doubt that that has resulted in the premature transaxle failures many RX300 owners are experiencing. The RX300 is not DBW so the engine torque is rising during the downshifts which would be needless were not priority given to upshifting so quickly.
  • hylynerhylyner Posts: 216
    Apparently Toyota disagrees with you
    I don't think that's true. If the manual says 1.2 seconds for your RX--which is either AWD or 4WD, I believe, then you're comparing apples and oranges. The .5 downshift time you refer to is a quote from their just published press release for the 07 Camry--a 6 speed tranny BTW. Whole 'nuther thing.

    "...something wrong..."
    If 1.2 nseconds is what the book says, and that's what one gets in their vehicle, then it's performing as designed--ergo--"nothing wrong." But then again, you're reading from an RX shop manual. This forum is for the ES 330.

    Ahhh, What the heck. It's Happy Hour here in the East!!
  • wwestwwest Posts: 10,706
    I would be willing to place bets that there is no difference between the 4-speed transaxle in my RX300 versus an equivalent MY V6/4-speed in any other Toyota/Lexus vehicle. I'll even carry that offer forward to any Toyota/Lexus V6/5-speed being the same as any other Toyota/Lexus V6/5-speed of equivalent engine capacity.

    Toyota is in business to make a profit, not to build unique transaxles for equivalent needs/applications.

    Otherwise the RX400h might very well be an RX270h using a "unique" I4.

    "....nothing wrong."

    And I don't disagree insofar as the transaxle taking 1.2 seconds to complete a downshift. What is actually wrong is that the firmware design as it is today, giving such high priority to quickly upshifting, results in far too many inadvertent downshifts.

    And as (bad) luck would have it all three of the circumtances described in the TSB are ones in which the inadvertent downshifts are amongst the most stressful the transaxle will be expected to endure.

    Going from "cruise" O/D lockup into quick and rapid acceleration.

    Not good.
  • Any company that uses the tag-line "The Relentless Pursuit of Perfection" should expect high expectations.
    I guess that my major problem with this, beyond the actual problem with the car, is this: I view the ES as an entry level Lexus. I would expect to move up the chain within the Lexus line. However, when I experience this type of problem and get the reaction that I have from Lexus, I will am seriously put off.
    Just make the car work right, Lexus. But I don't expect that to happen. The problems that I have had with my car go beyond the transmission. I am tired of taking my car to the dealer for the same problem and not getting it fixed.
  • wwestwwest Posts: 10,706
    implied never reaching your goal the motto was changed.

    "The Passionate Pursuit of perfection"
  • nvbankernvbanker Posts: 7,285
    You're sure it's the Transmission, and not the throttle by wire design, that takes a fraction of a second to respond to throttle input? That's what I've heard it is.....
  • wwestwwest Posts: 10,706
    The DBW throttle is taking more than a second to respond to a newly depressed, or farther depressed, accelerator pedal but that aspect is intentional, embedded within the engine/transaxle ECU firmware.

    In order to protect the drivetrain, needless wearing of the frictional surfaces of the various clutches within the transaxle, the onset of engine torque is delayed via the DBW system until the resultant downshift is completed and the newly engaged clutches are fully and firmly seated.
  • es4jbes4jb Posts: 17
    1. Drive like a bat out of hell.
    2. Start fast off the line.
    3. Live the motto "the relentless pursuit of acceleration".
    4. Forget about "D". Drive in 4th gear. Leave "D" (overdrive) for highway cruising speeds or geezers.
    5. Any time the transmission even considers downshifting, step on the accelerator like you MEAN it. Don't be a [non-permissible content removed].
    6. Downshift to 3rd gear just before entering a freeway on ramp.

    If you do this you will successfully train your Lexus to forget factory defaults entirely and drive like the real car it was meant to be. Help your vehicle find its real potential!
  • scoti1scoti1 Posts: 676
    Where do you live? I want to stay off the highways when in your neck of the woods, lol.

    I don't think this is how the learning process on these dbw's works. wwest has explained it before (and maybe will enlighten us again here, since I am not very technically astute) but what I believe he explained was that it resets itself each time you start and determines driving style within a few minutes of driving. This allows multiple drivers of a single car.
  • I agree that the problem is not actually the transmission. I do believe that the computer software is the problem, not the transmission hardware. However, I am using the word transmission to refer to the entire drivetrain.
  • So the DBW throttle delays acceleration to reduce friction and wear and tear in the transmission? Why don't they also design the brakes to delay or slow the application of the brake pads to the rotor? Won't this also reduce wear and tear on the brake system? Of course this will not be done because it is a safety hazard.
    When I step on the gas, I expect the car to accelerate. When it delays, it can cause me to be hit by another car, whether I am trying to merge and the acceleration is delayed or I am trying to avoid an oncoming car and the acceleration is delayed. This is the safety hazard that I see with this built in hesitation.
  • montiemontie Posts: 10
    There are a lot of unanswered questions in your post. NHTSA does not support the safety hazard condition you see. The wear and tear idea you mention isn't proven. It's just a concept tossed out by posters so there is no way of knowing if it's right or not. The built in heasitation theory does not appear to be there for everyone so how is that a done deal? Our ES 330 goes when you step on it so why does ours do it and yours doesn't? Just wondering.
  • I have seen releases from Lexus stating that the transmission performs the way it does to protect the transmission. I have also seen articles that describe the exact problems that I have with my ES. Lexus' response to these articles is to say that the transmission is "operating within design perameters". When I had the firmware upgrade done on my ES last year, the low speed hesitation was dramatically reduced. However, the higher speed hesitation is still very present.
  • motownusamotownusa Posts: 836
    I think some folks are passing their personal subjective opinion as facts which I think is a disservice to this board. While I understand some people might not like the way the transmission behaves; calling it a "problem" or "dangerous" without collaborating evidence is not called for. And yes Lexus has issued a TSB for those dissatisfied owners who don't like the way the tranny shifts. A TSB does not imply the transmission has a problem. It is just Toyota's/Lexus's attempt to satisfy the few owners who are unsatisfied with the tranny performance.
  • montiemontie Posts: 10
    I understand wher people are expressing personal opinions and that's alright with me. I think it's alright to question their opinions and that's what I did.
    Now I can't find any articles from Lexus about transmissions protecting the transmission or seen Lexus articles that describe the exact problems he says he has. All there is are posts like his saying that someone from Lexus said this or that. I question the existence of these articles and would be more sympathetic if I could find them but they don't seem to exist.
  • billranbillran Posts: 113
    motownusa, you are absolutely correct. And it is the distorted and exaggerated statements, presented as facts when they are not, that cause so much controversy.

    As you stated those statements are not only just a disservice to this board, but also discredit to some extent the claims of the few people who do indeed actually have a problem.

    The drivetrain, as designed, performs perfectly for me, my two coworkers and obviously for most of the owners of the hundreds of thousands of the cars on the road today.
  • user777user777 Posts: 3,341
    oh my, someone argues that the NHTSA hasn't even investigated hesitation, rather unintended acceleration, and we have you arguing NHTSA "does not support the safety condition you see".

    confused. to be fair, you're going to have to discuss this amongst yourselves so your position is consistent.

    montie, if a person driving their car feels unsafe, they are unsafe no matter what our opinions may be.
  • motownusamotownusa Posts: 836
    montie, if a person driving their car feels unsafe, they are unsafe no matter what our opinions may be.

    A person's personal feeling about something DOES NOT
    establish it as a fact. It is that person's personal feeling. I think the NHTSA is the most objective body of people who can decipher the fact from all the hype and rhetoric.

    someone argues that the NHTSA hasn't even investigated hesitation

    Gee, I wonder why ? I mean this discussion has been going on for four years now. Maybe the people running the NHTSA have concluded that the "problem" or "issue" or "glitch" or whatever else you want to call it does not constitute a safety concern. If you are really one of the owners who feel otherwise it would be better to just sell the car and buy something else. Regurgitating the same stale rhetoric day after day month after month does get a bit tiring.
  • wwestwwest Posts: 10,706
    when those that clearly admit that don't have the problem, have never experienced the problem, go on to state emphatically that it isn't unsafe or hazardous.

    Obviously I assume these complaints are real and maybe that makes it easier for me to imagine myself in the circumstances described, or maybe I have enough lifelong driving experience that I have encountered "like" circumstances.

    In any case I don't have any problem believing that a 1 or 2 second delay in engine response could potentially be a very frightening and therefore hazardous circumstance in most situations described in the TSB.
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