C7 auto transmission noise
Thread Starter
2nd Gear
Joined: Feb 2019
Posts: 2
Likes: 0
C7 auto transmission noise
I have 2017 about 25k mi, Torque convert replace under warranty. Have a high pitch noise when starting up, the car still under warranty. Noise started about 500 mi later, is this a problem with c7 trans, need help. Thanks
Team Owner
Joined: Sep 2000
Posts: 24,977
Likes: 2,690
From: Far NW 'burbs of Chicago
St. Jude Donor '13
Some details, please:
"When starting up"- when you first start the engine, or when you first start moving from a stop?
Is the noise there when sitting still in neutral? Sitting still in Drive?
Does the noise continue after you get up to speed?
Does the noise follow the engine rpm up and down?
Is the noise there in all gears?
Does the noise get better or worse when everything is warmed up?
I'm no tranny wizard, but others here might be able to help you if they have enough information.
"When starting up"- when you first start the engine, or when you first start moving from a stop?
Is the noise there when sitting still in neutral? Sitting still in Drive?
Does the noise continue after you get up to speed?
Does the noise follow the engine rpm up and down?
Is the noise there in all gears?
Does the noise get better or worse when everything is warmed up?
I'm no tranny wizard, but others here might be able to help you if they have enough information.
Burning Brakes
Joined: Apr 2018
Posts: 1,051
Likes: 690
Hook up a GoPro near the rear “windshield” or tape your cellphone there and record it. It’s impossible to tell if a knock or rattle or tick or whatever is “normal” without sound samples.
I has to record this and send it to some
mechanic friends, because GM botched the first “repair” attempt on this car. If I described the sound to them they’ll probably just tell me to bring them the car. Instead, with a video and audio attached to show when and how the noise occurs, to a man they all told me to “stop driving the f**king car and take it in ASAP before the engine grenade itself again.”
I has to record this and send it to some
mechanic friends, because GM botched the first “repair” attempt on this car. If I described the sound to them they’ll probably just tell me to bring them the car. Instead, with a video and audio attached to show when and how the noise occurs, to a man they all told me to “stop driving the f**king car and take it in ASAP before the engine grenade itself again.”
Advanced
Joined: Nov 2013
Posts: 64
Likes: 12
From: NJ
Do you hear a warble sound? If so, might be the below:
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https://gm-techlink.com/?p=13489Some 2014-2019 Corvette models equipped with the 6.2L V8 engine (RPO LT1) and 8L90 automatic transmission (RPO M5U) may have a warble-type sound coming from the rear of the vehicle with engine speed around 1,500 rpm. The sound may be more noticeable when driving up a slight grade with little throttle input.
The warble sound may be due to the bushing in the left-side differential cover having too much clearance. If the condition is found, replace the left-side differential cover and shaft seal. (Fig. 24)
Fig. 24
Use the DT-45000 Seal Remover to remove the differential rear axle shaft seal and the DT-48076 Rock Guard Installer to install the seal.
Refer to Bulletin #20-NA-041 for additional information and part numbers.
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https://gm-techlink.com/?p=13489Some 2014-2019 Corvette models equipped with the 6.2L V8 engine (RPO LT1) and 8L90 automatic transmission (RPO M5U) may have a warble-type sound coming from the rear of the vehicle with engine speed around 1,500 rpm. The sound may be more noticeable when driving up a slight grade with little throttle input.
The warble sound may be due to the bushing in the left-side differential cover having too much clearance. If the condition is found, replace the left-side differential cover and shaft seal. (Fig. 24)
Fig. 24Use the DT-45000 Seal Remover to remove the differential rear axle shaft seal and the DT-48076 Rock Guard Installer to install the seal.
Refer to Bulletin #20-NA-041 for additional information and part numbers.
Pro
Joined: Dec 2017
Posts: 687
Likes: 102
From: Albany NY
How did you get GM or the Dealer to replace the Tourque Converter? How many weeks did you loose your Vett for ? I'm in the same boat now. At 34,0000 miles on my '17 GS I'm tired of hearing the same warbble noise at 1,100-1,200 RPM under slight acceleration.
It will ware something out I'm sure. Kill my resale chances etc. I've had 2 tripple tranny fluses with the new fluid and before that a change out of all of the Diff fluid, no CHANGE IN NOISE.
It will ware something out I'm sure. Kill my resale chances etc. I've had 2 tripple tranny fluses with the new fluid and before that a change out of all of the Diff fluid, no CHANGE IN NOISE.
Cruising
Joined: Sep 2015
Posts: 14
Likes: 11
How did you get GM or the Dealer to replace the Tourque Converter? How many weeks did you loose your Vett for ? I'm in the same boat now. At 34,0000 miles on my '17 GS I'm tired of hearing the same warbble noise at 1,100-1,200 RPM under slight acceleration.
It will ware something out I'm sure. Kill my resale chances etc. I've had 2 tripple tranny fluses with the new fluid and before that a change out of all of the Diff fluid, no CHANGE IN NOISE.
It will ware something out I'm sure. Kill my resale chances etc. I've had 2 tripple tranny fluses with the new fluid and before that a change out of all of the Diff fluid, no CHANGE IN NOISE.
Have you tried the Range device? Just wondering if it has something to do with AFM.
The Range cured my problems with a ‘17 Grandsport.
