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2008 Toyota Sienna transmission NHTSA complaints: Power Train:Automatic Transmission

NHTSA — Power Train: Automatic Transmission Problems Seal Of


really awful
Crashes / Fires:
2 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
23,556 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2008 Toyota Sienna transmission problems

transmission problem

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2008 Toyota Sienna Owner Comments

problem #9

Jul 132011


  • miles


My 2008 Sienna hesitates when gas pedal is pressed after slowing down. The engine revs fast (engine is loud) but car does not respond accordingly by moving ahead until a couple of seconds later. Usually I would release the gas pedal to prevent the engine rev from going very high. This happens intermittently. Dealer could not replicate the problem and service manager explained that was probably caused by a delay in trying to get the correct shift. There was no tsb on the problem according to the manager.

- Staten Island, NY, USA

problem #8

Dec 312010

Sienna 6-cyl

  • 20,000 miles
Upon accelerating between first and second gear (7-15) miles an hour, especially after breaking, the vehicle hesitates as if it was in neutral. The RPM's go up but the car does not move. This mainly happens when making a right hand turn when not fully stopping. I also have had it happen when making a left hand turn going across traffic trying to get across the intersection. I have taken this vehicle in numerous times and the problem has never been reproduced by the service tech. I have taken them out on a drive along only to not reproduce it also. This is my main vehicle I drive my four children around in and I would hate to have this issue occur when I really need to accelerate and cause an accident. Apparently, I am not the only individual who owns this vehicle that had witnessed this hesitation problem. I believe this problem warrants further investigation and a possible recall/fix. This happens almost ever time I drive this vehicle.

- Yuba City, CA, USA

problem #7

Jul 222010


  • 15,000 miles
Pulled into parking space and vehicle suddenly accelerated and hopped onto curb and ran into pillar at a restaurant. Luckily nobody was eating on the sidewalk where van ended up. Placed vehicle into park and removed foot from brake and vehicle continued to lunge forward. Immediately hit brakes again and a bystander came to determine what was wrong. Talking to bystander to determine what happened, I took my foot off brake again and vehicle lunged forward (while still in park). Decided to shut vehicle off and have it towed to a dealership. I am awaiting a call from Toyota customer experience center to setup an inspection, however I went to dealership to pick up some things out of the car. I instructed the service agent that the van was not to be driven until the Toyota customer experience center inspector had a chance to look at the van with all parties. Next thing I know the service agent had pulled the van into the service bay for me to grab my belongings out of. I hope this did not ruin any data in the computer about what happened in the parking lot.

- Wildwood, MO, USA

problem #6

Jun 142010


  • 41,000 miles


The transmission does not respond to get the car into the first or lowest gear when pressing on accelerator if you do not come to a complete full stop at an intersection. It also appears that prior braking or slowing the vehicle as you come to a stop affects how the car shifts into gears and could be why it hesitates or hangs in no gear while trying to accelerate through an intersection or stop. This problem occurs at least 90% of the time. The response from the transmission while accelerating in these situations warrants a replacement or adjustment.

- Hebron, NH, USA

problem #5

Apr 282010


  • miles
2008 Toyota Sienna acceleration hesitation this minivan hesitates from driver acceleration for 1-2 seconds intermittently at very low speeds. However, the problem can be reproduced very easily by making a corner turn at low speed, and increasing acceleration after the turn. The minivan will not respond for 1-2 seconds before 'jumping' into the acceleration. The biggest safety issue with this is a left turn across an oncoming lane of traffic (similar to a corner turn). If I am coasting to the intersection for the turn, the minivan does not respond to the driver input for acceleration to get out of the way of the oncoming car (until through the intersection). Knowing this defect, I compensate for it, but an unsuspecting driver could have an accident with this defect.

- Franklin, MA, USA

problem #4

Aug 202009


  • 44,000 miles
2008 Toyota Sienna.

- Atlanta, GA, USA

problem #3

Feb 262010


  • 38,000 miles


I am concerned about the electronic control system in my 2008 Toyota Sienna van. Rather than the acceleration problems associated with the recalls, my van sometimes does not respond appropriately, eg. There is excessive hesitation and lack of acceleration when the gas pedal is depressed. There are other times, esp. Going downhill, when the car seems stuck in an unusually low gear (automatic transmission). When I've reported my concerns to the dealer (each time it's been serviced for 2 years!), the service rep says, "yes, my avalon does the same thing. It's because the gas pedal is no longer mechanically attached; instead it relies on radio waves which can be affected by temperature and humidity." So, while this does not appear to be as "dangerous" a problem as the unintended accelerations, I can imagine a scenario when I would need to accelerate, the car would not respond, and I could be rear-ended. I felt it was important to "report" this apparent problem, as the testimony I saw from Toyota officials seemed to heavily discount the possibility of there being problems with the electronic control systems. But something isn't right! I previously drove a 2000 Sienna and did not have any of the hesitation I have described above. (unfortunately, that engine "died" at 78K, I believe, due to the "white smoke" problem that had been subject of an earlier recall!) note: Stated date is most recent date van hesitated and was "stuck in a low gear." Problem first noted in Nov. 2007 with less than 1000 miles.

- Ellicott City, MD, USA

problem #2

Oct 312009


  • 31,000 miles
Problem occurs after slowing down at a stop sign or intersection at the speed between 5 to 10 mph and then go to increase speed. The transmission hesitates. One time the engine seemed to roar up, but the car didn't move.... this hesitation occurs when transmission is shifting at low speeds when accelerating after slowing down at an intersection or turning at a corner. This occurs intermittently but is quite noticeable. I can often reproduce hesitation with a hard brake followed by heavy throttle.

- Gettysburg, PA, USA

problem #1

Nov 012009


  • 23,000 miles
Unintended acceleration incident. Car was driven 200 miles the previous night and garaged. The next morning, car was started, backed out of driveway, and driven 15 mph for 1/4 mile until on main road. After traveling 0.4 miles on main road I slowed to a red light. The engine started racing (but not red-lining). I am absolutely sure my foot was not on the accelerator pedal. I shifted into neutral, which removed the forward pressure, and after a second or two, the rpms drifted back into the normal range. This is the most recent occurrence. Other instances have been less severe and have all occurred while braking the vehicle.

- Southborough, MA, USA

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