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Discussion Starter · #1 ·
So I have the 2011 Eco with 6spd automatic.
The AC suck is strong on that one!
In order to remedy not being roasted to death in 90+F degrees, I picked up the habit of harvesting kinetic energy, and routing it to the AC; meaning,
When I approach a stop light, or need to stop, I switch to manual, and shift one or two gears down.
This allows my car to engine brake better.
It will also allow my AC to be running at a decent speed, while the engine isn't putting any heat in the radiator; so that by the end of my stop, I can actually feel cool air coming out the vents!

AC and Freon is checked and all according to specs; the Cruze just sucks cooling down a car with the same AC system they used in both their smaller version Sonics, and their smallest 'Sparks'; is just not upto the task for the larger sized Cruze!

Anyway, this thread is about the clutch.
I don't want to destroy my engine, so after some trying out, I decided I would make sure the needle stays below 3k RPM when I downshift (2500RPM max).
I also downshift from 6->5->4->3rd gear, and then run it to 1500RPM, before i switch to N (going via D).
I found it doesn't benefit shifting into 2nd gear, as the engine RPM rises too hard, and downshifting to 2nd at 2500 RPM, my face ends up in the horn on the steering wheel.
I usually also don't let the needle drop below 1500RPM, and higher if I'm trying to stop faster; as engine braking only works on most slower braking practices.
Should I need to brake fast, the engine braking procedure, would actually impede with the brake pads (and the brake pads would need to slow down not only the car, but also slow down the engine which is trying to play catch up with the car).

That being said, I'm a little worried about how shifting into mid-RPM range often, would affect the clutch longevity?

I do put the vehicle in N, at almost every stop that's longer than a 1 to 2 seconds full stop, relieving the dual clutch from minimal wear at stop signs; and if start-stop speeds are below 5MPH, I sometimes roll in neutral; to somewhat compensate for the extra clutch wear during driving...

Anyone else applying engine braking (for better braking, slower speed than 1st gear idle, or better AC)?
 

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You do not have a dual clutch transmission so manual downshifting causes no harm. The transmission computer will not allow a downshift if speeds are too high so you can request a downshift at any speed and it will not occur until the TCM allows it.
This trans goes into a partial neutral at a stop so there is no need to manually select neutral.

Agreed, the A/C compressor is on the small side for this application......around town cooling is not great and the darker the car color the more evident it becomes.
Highway cooling is generally satisfactory so this gives further credibility to the compressor being on the small side.
Not much to add to that subject.

Rob
 

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Discussion Starter · #4 ·
You do not have a dual clutch transmission so manual downshifting causes no harm. The transmission computer will not allow a downshift if speeds are too high so you can request a downshift at any speed and it will not occur until the TCM allows it.
This trans goes into a partial neutral at a stop so there is no need to manually select neutral.

Agreed, the A/C compressor is on the small side for this application......around town cooling is not great and the darker the car color the more evident it becomes.
Highway cooling is generally satisfactory so this gives further credibility to the compressor being on the small side.
Not much to add to that subject.

Rob
Why don't I have a dual clutch transmission,
When I look online for the 2011 Cruze Eco 6SPD AUTO, it shows a dual dry clutch.
 

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Why don't I have a dual clutch transmission,
When I look online for the 2011 Cruze Eco 6SPD AUTO, it shows a dual dry clutch.
Because DCTs suck for city driving. Drive a Ford Focus and you'll know why.

Wikipedia GM-Ford 6 speed automatic. The 6T40 is a conventional torque converter automatic based off a joint effort between the two manufacturers and dates back to 2007 or so.

https://en.wikipedia.org/wiki/GM_6T40_transmission

https://en.wikipedia.org/wiki/GM-Ford_6-speed_automatic_transmission
 

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Discussion Starter · #6 ·
So, you're saying my 2011 cruze eco has a wet clutch?
It could explain why the RPMs sometimes are gradually lowering (from 2.25k to 2k rpm) when shifting.
 

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So, you're saying my 2011 cruze eco has a wet clutch?
It could explain why the RPMs sometimes are gradually lowering (from 2.25k to 2k rpm) when shifting.
Every automatic has clutch packs. It is neither a wet nor dry DCT. You have a normal torque converter automatic like every car of yesteryear. Please google its operation to find out more.
 

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Discussion Starter · #8 ·
Is there a reason why, when I'm in gear, pressing the accelerator, the RPM needle goes up, and when releasing it, it goes down, even though the engine keeps the same RPM?
(eg: Going uphill on a bridge, pressing the pedal results in a few hundreds of RPM increase on the needle, even without acceleration).
 

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Is there a reason why, when I'm in gear, pressing the accelerator, the RPM needle goes up, and when releasing it, it goes down, even though the engine keeps the same RPM?
(eg: Going uphill on a bridge, pressing the pedal results in a few hundreds of RPM increase on the needle, even without acceleration).
Torque converter unlocks.
 

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The clutch packs in a conventional automatic are not designed to slip - just release and apply. The torque converter, a type of fluid coupling, allows the shaft speed deficit (cushioning) between input and output. Once the transmission is in a certain gear the converter can lock up (by means of a separate clutch inside the converter) and save energy by not slipping and wasting power. When you mash on the gas the converter can then unlock again to allow the engine to rev a little higher, increasing power.
 
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Discussion Starter · #11 ·
Ok, so in layman terms, I have a clutch pack, which is dry, and I have a torque converter, which is wet.
 
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