noise at 45mph

[ewclement]

I have an 04 Tbird. For the last couple of years I've been hearing a rather high pitched noise that starts at 40 mph and reaches it loudest at 45mph, then seems to trail off. It also trails off if I leave off of the gas. I took the car to my local Ford dealer. They can hear the noise bout don’t know where it is coming from. Their best guess is in the rear end but they are not sure enough to do anything. Anybody have any experience with this animal or can give me some help on how to find the problem and fix it. Ed

[Welker]

Re: noise at 45mph

I replied but it sort of disappeared. It might still be repeated. Anyhow, I had the same noise in my o4 years ago. I have had the struts replaced, the transmission fluid drained and replaced and a rear ball joint replaced over the years. That's all the mechanical work and there may be no connection. I just noticed one day the noise was gone.

[JohnA]

Re: noise at 45mph

Ed, how many miles on the 'bird? I'm no expert, but you may want to start by servicing the rear end with a fluid cjange. This will give you new fluid and confirm that the level is correct, and won't cost a ton to try. John A

[ewclement]

Re: noise at 45mph

I have 99 k miles on the bird. All the 100k maintance was done including transmission and differential fluid replacements. Ed

[Rondor]

Re: noise at 45mph

Have you replaced tires lately?. I had a Ford several years ago that developed a similar sound and it ended up being a perfect combo if sounds from tread, exhaust, and driveline that produced a harmonic vibration at about 60 mph. When I replace tires ( years later) it went away. Very annoying and not uncommon I am told.

[ewclement]

Re: noise at 45mph

Yes. Tires have been teaced. Ed

[ewclement]

Re: noise at 45mph

Yes tires have been replaced. Ed

[Rondor]

Re: noise at 45mph

This can be a tuft one. So many things can effect this. A dyno might eliminate some possibilities, but this could narrow it down, If you have a local speedometer shop the may have a dyno and should run a check fairly reasonable.

[Cards]

Re: noise at 45mph

Don't forget the differential rubber grommet that hardens over time.

[pvkssarkis2004]

Re: noise at 45mph

Similar noise in one of our club members 03, he said the problem was a trailing arm. Bushings were dried out. Noise gone.