[Dewayne4608]

My car makes a whine/humming noise when I am driving around 34-45 mph and as soon as I let off the gas it goes away put foot back on and keep it there to maintain speed and I hear it again.

Any idea? 2003 CTS sport 68,000 miles

 

[dkozloski]

If it's coming from the rear your differential is shot. A couple of thousand bucks ought to take care of it.

 

[Spyke]

Dont worry. Maybe your differential is not shot. Mine has been doing this since I have it. It always with light throttle between 30 and 35 mph. I bought the car with 45k on it and it was doing this. Now, I'm more than 103k on my 05 and the sound is the same...

 

[Big_Ed]

Does sound like a musical note? Mine does the same thing. There were some threads around on noises...

http://www.cadillacforums.com/forums/cadillac-cts-forum-2003-through-2007/31465-front-engine-whine-gm-technical-documents.html

http://www.cadillacforums.com/forums/cadillac-cts-forum-2003-through-2007/137731-cady-tech-help-04-cts-howl.html

http://www.cadillacforums.com/forums/cadillac-cts-forum-2003-through-2007/12327-i-hear-howling-noise-when-accelerator.html

http://www.cadillacforums.com/forums/cadillac-cts-forum-2003-through-2007/113608-mechanics-please-look-i-need-your.html

To me the sound is almost like a vacuum hose or some type of pump or rushing fluid noise. There was another thread that I couldn't find where a guy changed the length and run of his heater hose to disrupt the harmonic forces... or something like that. I solved my problem by turning up the radio.

 

[tommy compton]

If it's coming from the rear your differential is shot. A couple of thousand bucks ought to take care of it.

you're such a ray of sunshine.

 

[z06bigbird]

you're such a ray of sunshine.

That is why his parents called him Sunny. He must have gotten up on wrong side of bed. He is usually very helpful.

 

[tommy compton]

lol i think he's banished from the sts forum for his helpfullness that's why we are blessed with his sunny rays.

 

[jrnor666]

Ring and pinion. This from a old mechanic. She might go 200,000 with the whine.
Don't sweat it til it pops.