I don't know what I'm hearing??

[Jim Cook]

I already know that I made a mistake rotating my Goodyear tires but I have a crazy sound coming from the rear end of my 03 sport trac 4x2. I hear what sounds like a turbo spooling up or that whirring noise you hear from a supercharger...I have neither! The sound is so loud that I thought that I was just hearing road noise due to the rear window not closing and sealing completely...no dice! The noise happens any time I am stepping on the gas at any speed and is even audible at 70+ mph! Do fuel pumps make that kind of noise? Would a rear end make a noise only when you give it gas? Does anyone have or have you had an experience like that? (03 Sport Trac XLT 4x2 4:10 limited slip rear)

 

[FlipTrac_511]

My 04 is also 4x2 w/ 4:10 limited slip, and when I have the rear/backlight window open I always hear a whine during acceleration, say like when jumping on the freeway. But I wouldn't say it's loud at all. Totally inaudible when the rear/backlight window is closed or in vent position. It is the differential. Everything is working fine so I've considered the whine normal, but your case may be different. I hope it's nothing serious.

 

[Jerry Gerner 2]

Last time I had noises like you describe was when I blew the spider gears in my old '98 S-10 lsted awhile but when they scattered I was dead in the water. Hopefuuly this isn't the case for you but you might want to take it to a tranny shop and take them for a test drive so they can tell you what they think.

 

[EddieS'04]

Last time I heard that sound it was pinion bearing. On a dodge van.

 

[Brian Curry]

Try rotating the tires back to the way they were . May be a tire.

 

[user 65037]

I had a similar problem a year ago and took it in to have it checked out. They took the differential cover off and filled it back up with a oil and a additive and it solved the problem. They told me that the additive worn out and just had to be replace with new fluid. Well /shurg it worked so it's all good.

 

[Jim Cook]

Problem started prior to rotating the tires...in fact it's been progressively annoying for the last 20 - 30k miles. Guess I will start with the diff fluid. Any reccomendations there? Or is ther e just one standard oil we're supposed to use?