Hey guys im new here and have an 01 3.8L V6 model that makes a humming noise (sounds high pitched but not loud) in the rear when I run it for long 45 minutes or longer. The sound doesn't always come out it's only sometimes. Not too sure what it could be but I've been told it could be my fuel pump but I won't be able to replace till this weekend. Any help or advice on what is causing this sound is appreciated.

 

try testing fuel pressure after it warms up

 

If it's a whirring/slight grinding sounds, you need new diff bearings...

 

a high pitched whine would be the pump

 

Does it do it with the car moving or does it go away with the car stopped?

If you shut the car off then just turn the key back on (without starting it) the pump should run for seveal seconds. It would be the ONLY thing in the back of the car doing anything.

If its your pump do not expect it to last very long. Most of the time once they start making noise you are hours away from a break down.

 

I have a similar problem as well. Except I think mine is coming from the exhaust area.

Does it sound like a high pitch hissing? Mine has been doing it since last year. If it was the pump, I'm sure it would have died by now.

 

im thinking the pump

 

I have a similar sound on mine, it's the "whirring" sound without any grinding as the car rolls at all speeds. I believe it could be worn gears, needing new rear diff fluid, or bearings....

 

I have the same problem and have already replaced the rear wheel bearings and diff fluid. I also replaced the rear drive shaft (carrier bearing) and that didn't fix it. hopefully it's not the gears.... that doesn't sound like any more fun than the 8 hours of work I have into fixing the problem.

 

the sound of those bearings have any thing to do with the time u drive the car?
I mean y after 45 minuets of driving?
temperature?