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Toyota Highlander Transmission Problems

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Comments

  • wwestwwest Posts: 10,706
    Your might want to keep in mind that up until just a few years ago EVERY 737 that Boeing built was DEFECTIVE. Every one of those was equipped with a multi-stage rudder hydraulic servomotor valve that had a rather serious design defect.

    Luckily only maybe 3 out of ~3000 crashed as a result.

    So every HL out there can be defective, seriously so, while most might never encounter the circumstances wherein that defect becomes critical to normal operations.
  • billranbillran Posts: 113
    Fair enough. In that case we could probably say that every car on the road could be defective in one way or another. No doubt your Lexus is defective as well in some way. I respect your opinion and knowledge and I know you and I have gone back and forth on this indirectly. There are an awful lot of people driving these cars without complaint, and mine has performed wonderfully under all types of conditions, so I still feel it wrong to condemn the entire line and suggest everyone dump them for Hondas, as a previous poster had.
  • user777user777 Posts: 3,341
    you make a good argument for avoiding mass hysteria and dumping one product line for another.

    however - there is ample evidence people need to exercise caution w.r.t. purchasing these advanced vehicles with "smart/adaptive" controls. even people that have test driven units which were fine at the time of purchase have ended up having issues later.

    the manufacturer and dealerships' ability to address these issues and completely satisfy the customer remain important.
  • tomdtomd Posts: 87
    My 2007 HL has 5,000 miles on it. This morning I was on the highway in the right lane and wanted to move over. I looked in my mirror and the person in the left lane was pretty far back so I gave it some gas and proceeded to get into the left lane. Well, it took between 1 and 2 seconds to "kick down" and when I looked in the mirror, the person in back of me was scaringly close. I guess when I want to pass, I have to make sure that I really step on it. My '99 Lexus ES300 had a similar delay so I don't think this is anything unique. Toyota transmissions have been criticized for downshift delay for years. I hope the '08 improves upon this. My wife's Mazda Tribute kicks down instantly. I don't understand why Toyota hasn't addressed this. They seem to have a fundmental flaw in their design philosophy regarding automatic transmissions. I can't believe that a company with all of their resources can't fix this. Apparently this can't be fixed with just software alone because they have tried this. I think there is a mechanical design limitation here. I keep going back to the same thing: Do they give their engineers the vehicles that they design to drive on a daily basis? I think they would uncover lots of problems before they become an issue.
  • wwestwwest Posts: 10,706
    Keep in mind that your 2007 HL doesn't have a manual clutch but for your own safety needs to act like you have one and are using it correctly.

    That's the design limitation the Toyota engineers hare been trying to get around since ~2000 for most modern FWD or front torque biased AWD vehicles.

    Not a simple task and insofar as I can see Ford (Edge) is the only marque having solved it, seemingly, so far.
  • tomdtomd Posts: 87
    Sorry wwest, but you lost me. I'm not sure what you are trying to say here. Can you explain?
  • wwestwwest Posts: 10,706
    There are times, places and circumstances wherein unintentional, inadvertent, engine compression braking, even slightly so, on a FWD vehicle can lead to loss of directional control. An icy downhill slope for instance, a place wherein you would normally disengage the clutch should you have one.

    The AAA is on record suggesting that vehicle owners with automatic transmissions practice quickly moving the shift level to neutral in preparation for times, as above, when this capability might mean avoiding an accident

    Engine compression braking can also interfere with ABS' ability to keep the front wheels rolling ever so slightly in some instances like the above.

    Since the manufacturers of these FWD vehicle cannot predict, forecast, or have a vehicle system(***) to detect these circumstances the best thing they can do is prevent engine compression braking on their FWD vehicles altogether, ALL the time.

    To that end late in the last century most manufacturers of FWD and front torque biased AWD vehicle modified the transaxle shift pattern. What now happens is when you lift the throttle, especially a FULL lift throttle, to enter a period of coastdown the transaxle will automatically upshift to alleviate any substantive level of engine compression braking.

    No big deal, right...?

    Wrong....!

    What if, just at the precise moment the transaxle BEGINS the upshift, you see an upcoming opening in traffic into which you wish to merge.

    So you FLOOR the gas pedal...

    1001, 1002, 1003....

    Oops, that "spot" in traffic just went by...

    What happened...??

    First, the transaxle had to complete the upshift, which undoubtedly would take 500 to 700 milliseconds. But now with the engine at idle there is no ATF pressure "reserve" to support a quick second sequential DOWN shift. So DBW was adopted to "protect the drive train". Allow enough time, again with the engine idling, for the ATF pump to build enough pressure to support, and complete, the upcoming downshift.

    Only then will DBW allow you to go forward.

    *** Ford was just granted a US patent over/for this very issue. The patented technique involves significantly reducing the level of regenerative braking of a hybrid vehicle (presumably applied to the FWD/AWD Escape and Mariner) if the OAT is near to or below freezing. The second technique involves INSTANTLY disabling regenerative braking if actual braking is applied and ABS activates.

    Obviously our vehicles could be modified to only perform the upshift sequence if the OAT is close to freezing. But that wouldn't take care of an oil and rain slicked street nor black ice in the shadow of a tree line at 10 AM.

    Just as obvious, the upshift would be too late and too slow if ABS were to activate during braking.

    Ford has also announced that the new Ford Edge has a variable displacement ATF pump. Presumably to allow a HIGH volume of ATF pressure/flow at engine idle if needed/required while at the same time not being HORRIBLY wasteful of FE by continuing to PUMP HIGH volumes of ATF at 6000 RPM.
  • tomdtomd Posts: 87
    Great explanation, makes a lot of sense! However, how do explain when driving along at say, 50 mph, the tranny is in it's top gear and you step on it to kick it down. Why does the Highlander seem to take so much longer to react than my wife's Mazda Tribute? Assuming that the software is taking the same amount of time in both vehicles to detect the change in throttle position and send the downshift command to the tranny (maybe this isn't true), the difference must be a mechanical design issue, no?
  • froggfrogg Posts: 16
    I continue to see posts on the subject. My experience is simple: The shift pattern on my Highlander is erratic. Even whenI have been the only driver for days, it is erratic. You might drive all around town, for example, and notice nothing unusual. Then, a block later, you step on the gas and as the trans leaves first, it doesn't go into second for a while. The engine revs up noticeably. If you are merging into traffic and this happens, you do the only knee-jerk thing: mash it. Of course, with the engine screaming, it really takes off when the trans engages. There are many other situations, including delayed downshifting when the problem is evident. I have had it to an independant mechanic, and he has verified that there is something wrong. Not an easy fix. Could be the computer. Could be a wiring harness. To fix it, a technician would have to spend some time with the car. Something that Toyota is not willing to do. They are only interested in reaching a point where they can declare the car....NORMAL. You hear that word - Normal - a lot when you take the car in, hoping to get it fixed. I have given up, and will get rid the car at the earliest convenience. As for those who love their Highlanders and are driving problem-free, I can only say that you are fortunate. But your happiness doesn't do anything to help me or others who have been stiff-armed by the company.
  • user777user777 Posts: 3,341
    that seems like you've got a bad transmission. i would consider this a safety problem. i think you're making a good decision by "moving forward" (in this case moving on).
  • tomdtomd Posts: 87
    It does sound like a bad tranny. I get the occasional slight downshift delay but I have NEVER experienced the aforementioned scenario where the tranny leaves first gear and doesn't shift into second for a while.
  • user777user777 Posts: 3,341
    at some point i think you have to follow your gut feel. it's one thing to have one odd behavior, but multiple and unpredicatble ones?

    toyota should know when "enough is enough" and give a good customer a break.

    i'm not sure this person has had someone check the fluid level in the transmission. if it were grossly off, i could see how the inconsistent behavior could arise...

    possibly even some bad shift solenoids...

    but, otherwise, it doesn't seem like a transmission control computer programming/flash issue, or wiring problem. it also doesn't seem accelerator sensor or throttle position sensor related either.

    if they haven't done anything for the customer, you'd think they'd replace the transmission. they've been doing that for some of the owners of new camrys (at least).
  • wwestwwest Posts: 10,706
    Is anyone with a Toyota or Lexus RWD or rear torque biased AWD/4WD having these kinds of problems, downshift delay or engine revving between upshifts?

    TSB for either RWD or..?

    Anyone...??
  • jamo22jamo22 Posts: 2
    I have a 2006 Toyota Highlander & the Transmission shifting pattern is so erratic and unpredictable that it causes me to continually tromping on the gas pedal and become an agressive driver.
    Too many times, I have stepped on the gas & the car just goes into a time lag before it finally shifts.
    I have taken it to Toyota & they tell me mall is well, and that it shifts, not on a preset pattern, but based on a sensor that determines your velocity & if you are trying to increase or decrease. It is a very poor explanation and even poorer transmission.
    My wife has a 2002 Highlander with electronic transmission & it learns your driving pattern & adjusts accordingly. It is great. What happened Toyota?
  • jamo22jamo22 Posts: 2
    Read my post, you are not alone & it is not limited to RWD.
    Jim
  • user777user777 Posts: 3,341
    go to another dealership, and get their "it's operating normally" in writing.

    video tape what your car is doing and diplomatically, with the help of a lawyer, suggest to toyota that either they fix the vehicle, buy you out, or you post it.

    toyota needs to be shamed a whole lot more i guess into "moving forward" and taking care of it's owners with shifting problems in their brand new rides.

    your dealer is giving you the party line.

    you may need a TSB, and that might help some, but more likely, you have a defective part in one of these areas:

    torque convertor,
    transmission,
    throttle body assembly,
    accelerator pedal assembly
  • I have a 2003 HL with automatic transmission. Arriving home today, my shift surprisingly would not let me set to Park without extreme use of force on the shift button and lever both. It will not crank in Park anymore. I now have to force it back out of Park and put it in Neutral to crank the engine. Shifting works fine except for Park. Has anyone experienced anything similar and if so do you know what caused the problem?
  • I bought a Toyota Highlander from a Maryland Dealer on April 1, 2007 and this car has some serious problems. The entire throttling, shifting, and braking mechanism is out of whack. When you start the car it idles at 1500 RPM. Then when the car warms up the car's idle speed is so high that the car will go 25 mph on its own (on level ground). The car has a tendency to accelerate erratically going from first to third gear.

    Shortly after I purchased the car I took the car back to the Toyota Dealer and told them about this erratic throttling/shifting problem and they insist "its normal". This explanation is basically baloney and indicates to me that Toyota executives know they have a problem. The Toyota company have apparently instructed the dealers to use this standard line "Its normal". They even made me sign a statement when I picked up the car that the 3 problems I had complants about were "Normal". So the dealer refused to do anything about the problem. The salesman also indicated this is "Normal". Same lingo (how strange).

    The car is dangerous because the throttle speeed is set to high and I am very apprehensive regarding winter weather (approaching) with the car accelerating when I want to slow down.

    The car I purchased was masde in Newark, New Jersey and I bring up this point to warn any one who is contemplating purchasing a New Toyota Highlander should be extremely cautious if they discover the car was manufactured in Newark, NJ. Drive the car alone and test drive it at least twice because the problems aren't readily noticeable all the time.

    I have now had the car about 7 months and its a lemon and also very very dangerous. I pray I won't get into a terrible accident this winter when throttling and shifting problems could become a potential "death trap".

    Dave
  • Sorry to hear about your troubles. One note, though: I don't think Toyota has a plant in Newark, NJ, do they?
  • Having the same problem here as well, also a 2003 Highlander. The problem started randomly about a year ago and has gotten progressively worse, now to the point where it is a real inconvenience. A friend told me that it is a linkage adjustment between the shifter and the transmission, but I think it may be the park safety interlock hanging up. Anyone with some answers please help us!!! andypando@msn.com
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