High pitch humming noise whenever i go above 67mph...and only when i push on the gas

[jdawg]

Ok, so i just got my car in august, and i purchased an extended warranty for it which lasts until it gets to 75,000 miles... i only have 32k on it right now... ive noticed that whenever i get to 67mph the car starts making a high pitch buzzing (humming) type of noise.. it only starts to hummmm when i reach 67 mph or more.. and it continues humming at any point that i give it some gas.. if i let of the gas pedal, the humming goes away... and then when i start to give it gas again the humming starts again.. basically if im just coasting above 67 theres no humming. what is the deal with that? is anyone having the same problem? its reallly annoyingg and i took it into the dealer and they hear it too, but they said they cant really tell what its coming from and if it gets louder to bring it back in and they can try to look at it more closely...

any suggestions?

[TomPierce]

It is the rear transmission mount resonating with the frequency of 6th gear. There is a bulletin about it. (I think there is also a revised transmission mount released if the below fix does not work).

Service Fix
6th Gear whine at approx. 110kmh
VE, WM, V8-6L80E 6Speed A/T
Group 7B Ref. No. TL 1637-0806


CONDITION
When the vehicle is cruising at around the 110km/h in 6th gear, a very high pitched noise may be heard. Once the speed either increases or decreases outside this speed range of 100km/h to 120km/h the noise seems to go away. The frequency at which this peaks is 1240Hz.
This noise is only heard whilst in 6th gear.


CAUSE
The transmission mount upper plate rigidity and mass has been detemined to have a large influence over the transmissibility of the 6th gear mesh frequency into the body structure.


CORRECTION
After verifying that customer complaint vehicle has condition as described above , proceed as follows:


1. Thoroughly clean the surface of the top bracket on the trasmission mount with Prepsol, then dry the area.


IMPORTANT: it is essential that all due care is taken to ensure the components which are used for the adhesion of the weights are perfectly clean prior to fitment of any weights.


2. Apply 140g of stick-on wheel weights to the top LHS of the bracket. (Refer figures 1&2) if weights need to be stacked on top of one another, ensure that the top surface of the weights are also cleaned in the same manner as above.


This additional mass will eliminate the frequency at which the top plate emits the whine condition. DO NOT attempet any other method of mass attachment, other than that stated above.


Figure 1. Location of weights to fitted, snown from above.


Figure 2. Location of weights once fitted.


DO NOT REPLACE THE TRANSMISSION for this condition;
it will NOT rectify the fault!


WARRANTY CLAIM INFORMATION
Description Apply weights to A/T mount
Labour Op. No. J000830
Time 0.5 hr
Failure Code J0040 Noisy

[WickedMom]

Is it a solid humming noise or a strumming type noise?


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[jdawg]

thank you TomPierce. I will let the dealer know..
as far as the solid humming noise vs strumming type noise... im not sure what the difference is.. i can only describe it as a high pitched solid noise. it hums anytime i reach or go above 67mph but it will stop if i let go of the gas when im above that speed. as soon as i give it some gas again it starts the humming again..
idk if that answers your question or not..

[J Wikoff]

My dealer replaced the mount and it fixed that noise for me.

[Dunlin1]

I have the same noise only between 65 and 75 mph. I brought it to dealer (about a yr ago) and they said they can't replicate the noise as they are not allowed to drive over the 50mph speed limit BS ! What is the exact TSB # or Bulletin #. Does anyone have part # for new mount ? Thanks in advance.

[TomPierce]

What is the exact TSB # or Bulletin #. Does anyone have part # for new mount ?

It took less than a minute to search for the post with the new trans mount TSB number and part number. This information has already been posted if you take the time to search for it.

[bjhayes]

Good luck... My dealer gives me the "can't replicate" excuse... I'm gonna try again in a week when she goes back in.

[J Wikoff]

I forgot to mention, I had to take the shop foreman for a drive so he could here it. They wouldn't go fast enough on their own.

[todds87ss]

I have the same noise only between 65 and 75 mph. I brought it to dealer (about a yr ago) and they said they can't replicate the noise as they are not allowed to drive over the 50mph speed limit BS ! What is the exact TSB # or Bulletin #. Does anyone have part # for new mount ? Thanks in advance.
Ask them to go for a ride WITH YOU.