2006 Prius shudder when braking

[leeki4321]

I've been driving my 2006 Prius for about 3 weeks and put on little over 1000 miles. I keep noticing that whenever I brake, the car seems to shudder. It doesn't seem to be switching from gas/electric as noted by other postings. Does anyone else notice this? Is this normal for break in period?

[Astrotoy7]

Is this your first prius ? If so, teh regen braking takes a little getting used to. Basically, you dont need to be slamming the brakes with as much force as you may be used to on vehicles with conventional systems.

[SomervillePrius]

A shudder could also mean that your wheels are not alirgned.

But I do agree that the regen braking felt slightly different then normal braking so it could be related to that.

[Dripps]

I definately notice this on my husband's Lexus 400h (hybrid) but on my new Prius I can't feel that at all! The Lexus dealer said it was normal - basically the effect of having the braking energy converted to battery power.

[JMcPhee]

Originally posted by leeki4321@Jan 27 2006, 10:41 AM
I've been driving my 2006 Prius for about 3 weeks and put on little over 1000 miles.  I keep noticing that whenever I brake, the car seems to shudder.  It doesn't seem to be switching from gas/electric as noted by other postings.  Does anyone else notice this?  Is this normal for break in period?

[snapback]198679[/snapback]

As long as I break slowly and gradually, I can actually tell when its regenerating, and as I come down to less than 10mph and then to a stop, YES, it gets grabby. My foot's not moving, but the brakes feel like they're doing a grab-release-grab-release. I had to slam the brakes one time just a few days after I got the car (1/6/06), and originally thought it was due to that, but on a return visit to the dealer, I mentioned it, and they threw it up on the rack and checked. He told me all was fine. Yet here I brake, grab-release-grab, and always in the last few seconds, when it switches from regenerative braking to the actual discs I suppose. I'm still playing with it.

[leeki4321]

Originally posted by Astrotoy7@Jan 27 2006, 01:46 PM
Is this your first prius ?  If so, teh regen braking takes a little getting used to. Basically, you dont need to be slamming the brakes with as much force as you may be used to on vehicles with conventional systems.

[snapback]198685[/snapback]

I've actually driven a '05 prius for a while and it never happened. The new '06 seems to have different energy recovery logic. I also notice the battery level never goes below 2 bars like the older Prius. Hope the shuddering goes away..

[leeki4321]

Originally posted by JMcPhee@Jan 27 2006, 01:51 PM
As long as I break slowly and gradually, I can actually tell when its regenerating, and as I come down to less than 10mph and then to a stop, YES, it gets grabby.  My foot's not moving, but the brakes feel like they're doing a grab-release-grab-release.  I had to slam the brakes one time just a few days after I got the car (1/6/06), and originally thought it was due to that, but on a return visit to the dealer, I mentioned it, and they threw it up on the rack and checked.  He told me all was fine.  Yet here I brake, grab-release-grab, and always in the last few seconds, when it switches from regenerative braking to the actual discs I suppose.  I'm still playing with it.

[snapback]198693[/snapback]

Yes, the car shudders at the last few seconds before complete stop! Hope it goes away or they update the logic.

[bobr1]

Yes, we experience the "grabby" feeling in our 2006 at very low speeds.

You almost always get one "grab" when transitioning from regen to friction brakes at around 7 or 6 miles per hour.

But we have also noticed that if you are creeping along in slow traffic by slightly lifting your foot from the brake (as you might with any car with an automatic transmission), we can get a repetitive creep-grab-creep-grab feeling at about 3mph.

I don't remember this from our 1000+mi test drive of a 2005 Prius rental, but then that was mostly highway miles and we may not have noticed every idiosyncrasy.

Another way to tell when you are transitioning from regen to friction, if you tune in your hearing, is to listen for the whine of the inverter.

- Bob R.

[flynz4]

When I slow down... I usually push the brake very slightly and I can feel a long gradual deceleration which I know is not using the friction brakes at all... but instead is using regenerative braking. Then at 7mph, even though my foot pressure does not change at all... I can feel a slight release, and then a re-application of brakes when the regerneraive brakes dissengage, and the friction brakes kick in.

/Jim

[kbertsche]

Originally posted by leeki4321@Jan 27 2006, 09:41 AM
I've been driving my 2006 Prius for about 3 weeks and put on little over 1000 miles.  I keep noticing that whenever I brake, the car seems to shudder.  It doesn't seem to be switching from gas/electric as noted by other postings.  Does anyone else notice this?  Is this normal for break in period?

[snapback]198679[/snapback]

I notice something similar. I think it's due to the gas engine shutting off just before coming to a complete stop, and the engine exhibiting a small bit of "run-on" and sputtering as it tries to turn off. Better gas might help; you could try midgrade or premium to see if it reduces. I've thought about doing this but it doesn't bother me enough yet.

Kirk
San Jose