Transmission shift noise

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Jan 19, 2023 | 06:17 PM

JCALD

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From: Granbury, TX

Transmission shift noise

Under very light load and just before the transmission actually shifts, is it common to hear what I think are the clutch actuators? Kind of a metallic clink and scrape.

Jan 19, 2023 | 11:01 PM

itsonlyairandfuel

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AFM valves can make the noise you described. Try putting it in Z mode or track that should keep the afm valves open. See if the noise is still present.

Jan 21, 2023 | 10:17 PM

Andybump

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Quote:

Originally Posted by itsonlyairandfuel

AFM valves can make the noise you described. Try putting it in Z mode or track that should keep the afm valves open. See if the noise is still present.

That is a good recommendation. The AFM valves close when the engine transitions to V4 mode. To keep it out of V4 mode, the engine/shift setting has to be set to track (or Manual shift mode). That happens in Track Drive mode. In Z-Mode, the engine/shift setting can be operator selected. I think the engine/shift may default to Sport Mode (not certain). But, if the engine/shift setting is Sport, or any setting besides Track, the engine can go into V4 mode. I have heard (rarely) the AFM valves open and close. And I have also heard the tailpipe valves open and close with,squeak or a metallic sound. I have not noticed that sound at shift points though.

Jan 21, 2023 | 11:05 PM

JCALD

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From: Granbury, TX

I gave Z MODE a try and the noise is still present. I have service scheduled next week. Maybe they can clear this up for me.

Jan 23, 2023 | 09:28 AM

Cicio Performance

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From: Atlanta, GA

Quote:

Originally Posted by JCALD

I gave Z MODE a try and the noise is still present. I have service scheduled next week. Maybe they can clear this up for me.

We have seen solenoids in the trans stick which can cause issues and make sounds but if the car is driving good then that shouldn't be an issue.

Has the car been launched before?

Thanks
Andrew

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Jan 23, 2023 | 03:19 PM

JCALD

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From: Granbury, TX

I am waiting until 1500 miles before playing with launch control.

Jan 26, 2023 | 08:48 AM

JCALD

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From: Granbury, TX

After a dealer visit and having one of the transmission techs take a ride, it turns out to be one or both of the exhaust system valves when it goes from 8 to 4 mode under very light acceleration.

Dec 15, 2023 | 02:17 PM

vetteguy2019

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Quote:

Originally Posted by JCALD

After a dealer visit and having one of the transmission techs take a ride, it turns out to be one or both of the exhaust system valves when it goes from 8 to 4 mode under very light acceleration.

Mine does the same thing when downshifting so is it normal?