# 2011 "lurching" transmission



## Chevy_Country (Oct 16, 2015)

I've seen a ton of references to this "issue" on here but after searching or a while I don't find a thread that puts it together, I have an '11 Cruze LTZ and while usually it takes short drives a couple times a week this last week I've been in my work truck so much it saw some neglect, I dropped my wife off in Boston (50 miles one way) 

When I arrived after all the stop and go, I noticed what must have been what he overs on his forum refer to as "lurching". I'm not sure if that's the word that best describes it, it felt as though in stop and go hitting the gas for a short second then hitting the brakes soon after e car slowed down but didn't shift to neutral like it would in a longer stretch of drive.

When this happens it feels as though it's a manual in second gear with your foot on brake and gas to keep it running, it wants to move. When I let go of the brake it'll inch forward like normal, doesn't actually shoot forward just feels like it wants to.

I understand this is a "2011 thing" I guess I'm just curious as to what's happening, if someone can explain to me what's going wrong maybe I'll feel better about it happening, and I'm ordering a BNR tune before the summers over, is this a tune issue that the BNR will fix or is this what I'm looking at forever. 

Thanks for any information!!


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## Robby (Mar 1, 2013)

I'm not certain if your description of events lines up with normal operation.

The trans is designed to go into a 'partial' neutral when stopped, in drive, brake applied. Partial, in this case, means that if you reduce brake pedal pressure a bit, the car will 'creep' but still not be fully engaged.......if you fully release the brake pedal, you will feel full engagement occur in a second or less.
This is, to those unfamiliar with the design, referred to as a 'lurch'. It can be far more pronounced by drivers who 'two foot'.....a description of those that operate the car with left foot brake application.

When 'two footed' it is easy to begin to apply throttle before fully releasing the brake, resulting in a feeling the same as a 'neutral drop'.

A neutral drop is a teenager trick......rev the engine, flick into drive, the wheels will spin on engagement (or the trans comes apart).
I'm using this as a extreme example to help define what I'm describing here.

I will agree, the MY2011 versions were a bit harsh during the transition and it seemed as each new model came out Chevy had the re-engagement 'thud' smoothed out.

My 2012 Cruze was noticeable if I was paying attention.....my 2015 Trax (same engine/trans) is almost imperceptible.

Hope I'm not wasting your (or my) time with this response but it is an attempt at clarification to your concern.

Rob


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## Chevy_Country (Oct 16, 2015)

Robby said:


> I'm not certain if your description of events lines up with normal operation.
> 
> The trans is designed to go into a 'partial' neutral when stopped, in drive, brake applied. Partial, in this case, means that if you reduce brake pedal pressure a bit, the car will 'creep' but still not be fully engaged.......if you fully release the brake pedal, you will feel full engagement occur in a second or less.
> This is, to those unfamiliar with the design, referred to as a 'lurch'. It can be far more pronounced by drivers who 'two foot'.....a description of those that operate the car with left foot brake application.
> ...


That certainly clarifies the design purpose, however mine was seeming to not enter the partial neutral at all in the stop and go traffic, once on the main roads with longer points of travel between stop it operated normal.

my concern is I've seen some posts about how the 2011 years and early 2012s had some issue that they had corrected at some point on 2012 for the early 2013 model years, if I can understand what that is I can correct my driving habits at the bare minimum

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## Robby (Mar 1, 2013)

The only problem I remember being corrected was for the trans re-engaging/dis-engaging at one to three second intervals when stopped with brake applied.......felt like someone kept bumping into the rear of the car.

The repair involved replacement of the apply clutches.

Rob


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## jblackburn (Apr 14, 2012)

Like Robby said, if it feels like the car is lurching at a complete stop with your foot on the brake, the clutches are grabbing and need to be replaced. That can be a very expensive rebuild out of warranty. 

If it's just jerky in stop and go while moving, I think that's just a 6T40 thing. The early years were absolutely terrible in traffic where they can't decide what gear to be in or are shifting constantly; my 2016 with the redesigned 6T35 can get on my nerves at times with clunky shifts as well.


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## Chevy_Country (Oct 16, 2015)

jblackburn said:


> Like Robby said, if it feels like the car is lurching at a complete stop with your foot on the brake, the clutches are grabbing and need to be replaced. That can be a very expensive rebuild out of warranty.
> 
> If it's just jerky in stop and go while moving, I think that's just a 6T40 thing. The early years were absolutely terrible in traffic where they can't decide what gear to be in or are shifting constantly; my 2016 with the redesigned 6T35 can get on my nerves at times with clunky shifts as well.


It feels like that, however when I let go of the brakes it rolls forward normally, it's only when I'm in stoovand go traffic

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