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I have Chevrolet Cruze 2014 hatchback Eco, automatic.

I've noticed the following issue: In each ignition, the first time the transmission transmits into 3rd gear it makes a subtle grinding noise which can be felt in the gas paddle. [nothing too loud]

This phenomena will not repeat itself (when entering 3rd gear) again unless the engine has been shut down. It won't happen either if (in the first time since the engine was off) I've entered 3rd gear manually (and than later in D mode it won't happen again either).

The mechanic was clueless and was unable to explain what might be the problem. They've updated the computer software version but it did not help.

any leads will be highly appreciated! Thanks!!

  • Welcome to the site. We need some more information. Is the check engine light on, or any codes stored? Has the scheduled maintenance of the transmission been completed? What is the level of and the condition of the transmission fluid? Have you taken it to a transmission specialist? – CharlieRB Mar 20 '18 at 12:34
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I found this thread that seems to describe what you're having an issue with. It appears to be normal for the vehicle as it's part of its self tests that it runs. If you read through the thread itself, you'll find several others describing issues similar to yours. The below excerpt was posted in response to them.

http://www.cruzetalk.com/forum/34-gen1-1-4l-turbo/22002-3rd-gear-20mph-shudder-drivetrain-6.html#/topics/22002

The electronic brake control module (EBCM) is able to detect many malfunctions whenever the ignition is ON. However, certain failures cannot be detected unless active diagnostic tests are performed on the components. Shorted solenoid coil or motor windings, for example, cannot be detected until the components are commanded ON by the EBCM. Therefore, a power-up self-test is required at the beginning of each ignition cycle to verify correct operation of components before the various control systems can be enabled. The EBCM performs the first phase of the power-up self-test when the ignition is first turned ON. The system relay, solenoids and the ABS pump motor are commanded ON and OFF to verify proper operation and the EBCM verifies the ability to return the system to base braking in the event of a failure. The master cylinder pressure sensor performs a self-test by sending a series of specific voltage signals to the EBCM, each for a predetermined amount of time. This phase of the power-up self-test may be heard by the driver, depending on how soon the engine is cranked and started after turning ON the ignition. The second phase of the power-up self-test begins when the vehicle is driven at a speed greater than 12 km/h (7.5 mph) and the EBCM has not detected any traction control module (TCS)/vehicle stability enhancement system (VSES) related malfunctions thus far. When the brake switch indicates that the brake is not applied and the master cylinder pressure is detected as being low, the EBCM proceeds with the test. The EBCM isolates all of the wheels by closing the 4 isolation valves. Due to the fact that all of the wheels are isolated during the second phase of the test, the test must be aborted if the brake is applied while the test is being performed. Occasionally, the driver may detect this by experiencing a momentary hard pedal.

  • The Op is talking about transmission and the gas pedal, you have an answer about the brakes, brake pedal and master cylinder... – Solar Mike Mar 20 '18 at 14:02
  • One of the posts from the thread: "Here is what happens... start the car, put into gear and accelerate.... first, second, third... keep accelerating to 20ish mph, and SHUDDER.... then shift into fourth.... NOW, if I stop and pull over and try it again NO shudder. BUT, if I stop and turn the key off and try it again SHUDDER.... EVERY. SINGLE. TIME. So easily to replicate.... what is confusing me is that it ONLY does it the first time after being started and never seems to do it again. Anyone else ever hear of this or had this happen to them?" – iDriveSidewayz Mar 20 '18 at 15:17
  • Just because something appears in the gas pedal doesn't mean it's limited to only the gas pedal. – iDriveSidewayz Mar 20 '18 at 15:18
  • Just because it happens when shifting into 3rd gear doesn't mean it's in the transmission. Driveline shudder is subtle enough to be misinterpreted. I think it's a great, relevant, specific answer. I would suggest the OP immediately stabs at the breaks the next time it occurs (or "test" it by repeatedly restarting and forcing it to happen) to see if it "cancels" the shudder effect - like the excerpt mentions. The phenomena is consistent enough that it might likely be an "intentional" effect of the brake/TCS test - just as the answer alludes to. – SteveRacer Mar 21 '18 at 1:03
  • Thank you all for the replies. really appreciate it! I do think it's gear related since it doesn't replicate when i'm shifting gears manually. I'll test it later today and post what happened (i'll slowly accelerate to ~30mph on 2nd gear and see if it reoccurs). @SteveRacer; it'll be hard to do that since it's very light and quick (less than 2/3 of a second). I won't be able to feel if it stopped or not. – orialz Mar 22 '18 at 13:44

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