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Consumer Reports description of the brakes was somewhat worrisome: "The Sienna turned in a subpar braking performance overall, with not only long stops but also a difficult-to-modulate brake pedal. Stopping distances were well below average on both dry and wet surfaces. Toyota has issued a TSB (Technical Service Bulletin) to rectify the problem for existing customers." Any specific comments on how troublesome they are (and how much Toyota will be able to fix them?). My 2010 Prius brakes have been lousy for different reasons I suppose...
 

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Do you know the TSB number? I agree the brakes were something I had to get used to. Definitely different feel from any non-hybrid I have driven previously. Since this is my first hybrid I just assumed this is just something common to all and something you just had to adjust to. It is not a big deal but if there is something available to make it feel more "normal", I'd like to try it.
 

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I found that if there was sudden braking, especially at slow speed, the brakes felt mushy for about an inch, then too grabby. However, under normal driving, after coasting for a second before applying the brakes, and then applying steadily increasing brake pressure it felt totally normal.
 

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Consumer Reports description of the brakes was somewhat worrisome: "The Sienna turned in a subpar braking performance overall, with not only long stops but also a difficult-to-modulate brake pedal. Stopping distances were well below average on both dry and wet surfaces. Toyota has issued a TSB (Technical Service Bulletin) to rectify the problem for existing customers." Any specific comments on how troublesome they are (and how much Toyota will be able to fix them?). My 2010 Prius brakes have been lousy for different reasons I suppose...
The following is from the CR evaluation: "The Sienna turned in a subpar braking performance overall, with not only long stops but also a difficult-to-modulate brake pedal. Stopping distances were well below average on both dry and wet surfaces. Toyota has issued a TSB (Technical Service Bulletin) to rectify the problem for existing customers. Besides the long stopping distances, our drivers found the brakes to feel very non-linear, with an initial numb feeling when you first hit the brake pedal, followed by an annoying grabbiness when getting close to a stop."
I was unable to find the TSB that they are referring to.

The stopping distance for the Sienna was not radically different from the other minivans at 60 mph. Sienna is 148 dry/155 wet; Pacifica Hybrid 145/145; Pacifica 136/141; Honda 136/152. We are talking about half a vehicle length. The perception-reaction time for an automobile driver can vary from about 0.7 sec (66 ft @ 60 mph) in an expected situation to 1.5 sec (132 ft @ 60 mph) in a surprise situation.
Driver Reaction Time (visualexpert.com)

Personally, I think it is just a matter of getting used to the feel of the pedal. CR is just now performing their long term test of the 2021 Sienna so their evaluation may be based on their earlier short term trial of the pre-production model. They may not have driven it long enough to acclimate to the feel of the brake pedal.
 

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CR is just now performing their long term test of the 2021 Sienna so their evaluation may be based on their earlier short term trial of the pre-production model. They may not have driven it long enough to acclimate to the feel of the brake pedal.
They're done with their testing, which includes 2000 miles of a break-in period. They don't keep their vehicles much longer as there are several vehicles in the queue, so there is/was a white XLE for sale in CT.
 

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During the test drive the brakes were the main negative - it was also my first hybrid drive, but did not enjoy the "oh no, nothing's happening" initial moment, then the stiffer pedal and hard bite. Very non-linear and difficult to modulate.

If someone finds that TSB, please post it so we can see if this is something Toyota thinks they can fix or merely one of those "apply a sticker saying braking feel is different from normal cars".
 

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I've also experienced the "mush at first, then grab" feel with the brakes. I felt it is dangerous. I'm learning to brake sooner, which ends up much smoother.
On the other hand it may be that the brakes need some mileage of breaking in more. I do wish it was more linear. Sometimes it does surprise me.
 

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The brakes on the XLE I test drove in Nov 2020 felt mushy and nonresponsive. Both my wife and I noticed that issue. The brakes on our Platinum that we bought at the end of Jan 2021 felt much better. I wonder if they rectified the issue after the first month of production.
 

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The brakes on the XLE I test drove in Nov 2020 felt mushy and nonresponsive. Both my wife and I noticed that issue. The brakes on our Platinum that we bought at the end of Jan 2021 felt much better. I wonder if they rectified the issue after the first month of production.
I test drove a XLE a week ago, and the brake pedal modulation was very similar to my 2019 Avalon Hybrid, which I would call stable and predictable i.e. good. There were several video reviews conducted on pre-production models in late 2020 that commented that they did not like the brake feel in comparison to other Toyota Hybrids they experienced. So like you I wonder if this has been addressed by the TSB/later production, and the CR Test vehicle, although a purchased production model, maybe did not have the TSB applied?
 

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I test drove a XLE a week ago, and the brake pedal modulation was very similar to my 2019 Avalon Hybrid, which I would call stable and predictable i.e. good. There were several video reviews conducted on pre-production models in late 2020 that commented that they did not like the brake feel in comparison to other Toyota Hybrids they experienced. So like you I wonder if this has been addressed by the TSB/later production, and the CR Test vehicle, although a purchased production model, maybe did not have the TSB applied?
I do not have any problem with the brakes, in fact I like them. I let up on the accelerator and press the pedal lightly when I am some distance from where I will stop to signal that I plan to stop and thus initiate regenerative breaking. Then I gradually depress the pedal until I am using the brakes to come to a complete stop. The brake system is very sensitive to how fast and how far the pedal moves and responds accordingly.
 

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I've had/have two Siennas, 2009 and 2017, and don't have any complaints about braking. This is a large heavy car, and you should drive it with that in mind. Brake and tire wear are less than ideal, but I have no complaints about the few times I've needed to do an emergency stop.
 

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I do not have any problem with the brakes, in fact I like them. I let up on the accelerator and press the pedal lightly when I am some distance from where I will stop to signal that I plan to stop and thus initiate regenerative breaking. Then I gradually depress the pedal until I am using the brakes to come to a complete stop. The brake system is very sensitive to how fast and how far the pedal moves and responds accordingly.
You know that in this hybrid system it doesn't do much to intently regenerate, right?
Pressing lightly tells the car behind you you are braking, yet you let it slide for a long distance - that's called riding the brakes. The car behind you not only would get annoyed but have no idea when you are really stopping.
Having the brake sense what position it is at and to apply the brakes - that works only if its linear. Judging from your description, its not linear.
 

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You know that in this hybrid system it doesn't do much to intently regenerate, right?
Pressing lightly tells the car behind you you are braking, yet you let it slide for a long distance - that's called riding the brakes. The car behind you not only would get annoyed but have no idea when you are really stopping.
Having the brake sense what position it is at and to apply the brakes - that works only if its linear. Judging from your description, its not linear.
I do not ride the brakes for a long distance. I start applying the brakes at the distance required to come to a gentle stop. I am using regenerative braking to slow down to a few mph which is when the brakes are finally applied. I never experience the grabbing that people complain about. When you take your foot off the accelerator and press the brake pedal, you are providing input to a computer which first applies regenerative braking and finally applies the brakes to come to a complete stop. You are right, it is not linear with pedal position because the computer senses how fast the pedal is moving in addition to pedal position.
 

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I called up my dealer and when they displayed my VIN the TSB for the brakes popped up. I took it in and it took them about 1.5 hrs to do what they called a calibration. They said I was the first one they had done and it was all done on the computer. The end result was a significant improvement. The feel is much more linear and they have not grabbed yet. I highly recommend anyone with a 2021 to have this done.
 

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Hmm... good to hear that. It is along with the middle seat's base that is not removable a big minus for me. But if this solves a major drive ability issue, then things are looking better for the Sienna.
 

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I called up my dealer and when they displayed my VIN the TSB for the brakes popped up. I took it in and it took them about 1.5 hrs to do what they called a calibration. They said I was the first one they had done and it was all done on the computer. The end result was a significant improvement. The feel is much more linear and they have not grabbed yet. I highly recommend anyone with a 2021 to have this done.
Nice!

I put in my VIN on toyota.com but its showing nothing. I suppose it will get rolled out to all soon?
 

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Nice!

I put in my VIN on toyota.com but its showing nothing. I suppose it will get rolled out to all soon?
NHTSA website showing 17 communications for 2021 Sienna, but it is not showing any details of what these 17 TSBs are ??

 

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NHTSA website showing 17 communications for 2021 Sienna, but it is not showing any details of what these 17 TSBs are ??

Thanks. Will keep checking. I think I had checked it earlier, and today it got me 0 hits too for my VIN.
 
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