Rear End growling/whining

[Honkytonkman]

Hello!
Sorry if this is a repost, but new to the site, and have searched alittle around without finding the answers to my problem!

I just bougth an 2004 Expedition, Eddie Bauer edition.
it has about 90k miles on it, and the car runs great other than sounds that seems to come from the rear differential,.

Today i changed the rear diff fluid, and it was old and metallic, and startet searching the web for replacement parts. (wich i was not able to find)

so i have a couple of questions, Should i worry about the sounds ? Is it going to break ? Last ownes said that it have always made that sound while he was the owner.

and secondly, WHERE could i buy replacement parts to get rid of this problem ? cant seem to find it anywhere.

And how do i recognise the what transmission i have ?
VIN decoder ? where could i find something like that ?

Thanks for any replies.

 

[Honkytonkman]

BUMP!

I have a hard time beiliving that nobody here know something about this.

 

[panda24619]

does the sound go up when your on the freeway and go down when your slowing down?
mine does the same sound. 167k miles and i just ignore it. ive changed my fluid and looked in my diff and nothing wrong. i actually think its my u joints, but idk. i have to change those and see if that helps.

 

[Honkytonkman]

Sound get higher pitch the faster i drive, starts at about 35-40 mph and then accelerates in volume and pitch... ONLY when i have my foot on the throttle, soon as i let up the sound quits.. changed oil, checked joints, nothing wrong other than the sound. and when the car in it self is so quiet, it gets kind of annoying.

 

[panda24619]

4wd?

 

[Honkytonkman]

yes 4wd... but sound appears if driving only in 2wd . and is definetively coming from the rear diff. So all i really want to know is if this is harmful ? should i rebuild my rear end ? or should i just put in some Omega diff oil or some additive and drive?

 

[panda24619]

okay. well if your sure its the rear then its the rear. umm... ive had the noise in mine for 167k. but if your really worried about it i would rebuild the rear. new bearings should do the trick. not that hard of a task, just time consuming. and you have to know what your doing. and yours is a little bit different than mine. ive never changed anything in a IRS. just soild axles. so as for helping you with installing anything im NOT the right guy for the job. but your sould seems to be bearings. i think thats what mine are, if its not the ujoints.

 

[Honkytonkman]

I'm not worried about how to do it.. i just want to know if i should care about it.
I bought the car because of its reliability.. and every test i have read states that this is a very reliable car... but when i heard the noise in the diff i tried to find out about it on the web, and found lots of issues with this. but what I have yet to find out is if it's going to eventually fall apart , or if it will just continue to make that sound ? the previous owner (had only owned the car for a year or so) said that it had always made that sound.. and he did not bother to get it checked.

 

[Honkytonkman]

So nobody can tell me is this is going to end in disaster or if i should just drive and forget about it ?

 

[Rod240sx]

hard to say buddy... it's the type of thing that you never know what can happen. Like Panda said, he's had it for some time now and hasn't had a problem...

I'm really nit-picky about my cars and if I had a noise like that it would freak me out, so get it fixed and give yourself some piece of mind... Since these trucks have independent rear suspension, another idea is to tray to can find a low mileage diff from a local junk yard and swap it in. My guess is that it would probably take a fraction of the time compared to rebuilding the one you have.

Not sure if this is a common problem as it's the first time I've heard of it; however, maybe it's related or linked to the differential leaks that are somewhat common? At some point of your trucks life, the diff could have leaked its fluids and by the time it was repaired or acknowledged, it could have been empty or close to empty for several hundreds or thousands of miles.

I know I had to get mine fixed on my truck when I first purchased it. I Did a full inspection when I brought it home and noticed the leak - the diff was very low on oil

 

[Honkytonkman]

I see complete rebuilt units in the US for about 500$ but not quite sure wich one to get...
My axle code is 16.
and another thing is , these cars are not so very common here in norway, so yunkyards dont really have that much of them, and the shipping from US to norway cost quite a bit..
so i would have to consider rebuilding.

 

[BrandonH13]

We had this problem on our limited explorer. After searching around and around it finally came down to its the rack and pinion in the rear end. A tech from ford said that if its under or over tightened then it will make the whine noise.
They also said that it would be the wheel bearing going bad if I remember correctly.
You can go to explorerforum.com and look. Almost everyone with the 02-05 had "whiney" rear ends when on the gas, but no noise if you let off

 

[Honkytonkman]

I am going to try some special lube from Omega for this rear! a local mechanic has used this on several vehicles with whining in the rear end with great success!
It costs about 480$ a gallon, so i hope it helps. recently i also got shudder in my transmisson. that sucks, I get so cought up in strange sounds in the car, it really ****** me off. i Thougt these cars also were "built ford tough" like an F-250 Powerstroke that i previously owned, hundreds of thousands of miles with no issues at all, only regular service.