Strangest sound on the planet!!

[MagikMan]

I have a 1995 Explorer 4WD with, I don't know what sound. A week ago my wife was driving and she said she hear a loud whizzing noise but it didn't sound like it was coming from the car. But it was loud. I thought of a pulley bearing and check to find tha1) belt was warn but not excessive, tensioner was noisy, and the AC replacement pulley was a little loose. I replaced the belt, tensioner, AC replacement pulley, and for extra fun the idler pulley. Great! Took it for a test drive and the noise was not any of those. Come to find out that at speeds over 45 mph when coasting with no load on the drive train, a loud spinning starts rather quickly and goes up and down in speed (by the sound) until you put a load on the drive train or you slow down. A 'Ford Man' in my area took a ride with me and he thinks its like its coming from the front drivers hub. When I bought this car a year ago the passenger side front needed almost everything new hub, brakes, lower arm (? just paid didn't do the work). So does anyone have an idea of what the free running sound is or where its coming from? Any help would be appreciated as I am running on 0.

 

[1992fordgreen]

Wheel bearings?

 

[Travisfab]

This may sound odd, but could it possibly be coming from your speakers?

 

[koda2000]

This may sound odd, but could it possibly be coming from your speakers?

humph, I thought I was the only one this ever happened to. the noise was so loud my wife said that people were looking to see where the noise was coming from. it finally did it with me driving. the radio was on, but turned down all the way. the noise was coming from one of the speakers. I turned the radio off, no more noise.

 

[MagikMan]

A few more things...

No not speakers the radio was both off and on and the sound was still there as loud and as baffling as ever! The sound is just like those toy cars you push on the carpet to get a flywheel spun up to speed and let them go and watch them run. Now imagine that sound if the flywheel bearing surface was worn loose and slightly elongated. Today I noticed that if you hear that sound and slowly apply gas to tighten up the drive train a discernible 'clunk' can be felt when the sound stops. It seems to me that I will have to use the ole tried and true 'shotgun' method of car repair. That is figure out about where the problem is and change all the parts in that area until the problem is fixed. I'm afraid if I don't find it soon I will be forced to stop driving it completely. I live out in Amish country and it just is not a viable solution. So fix it I must, with or without a clue as to what is actually wrong. So any and all hints/help will be appreciated.

 

[drdoom]

Transfer case is going out. Also check to be certain tire circumference matches on all four wheels.

 

[drdoom]

Don't shotgun it, I can tell you exactly what you need, cost you between $150-350 depending upon certain wear points. Its an easy R&R, and the bench work is easy as well. And seriously have a look at the tires that could be the problem as well. Circumference must matchb within a quarter inch or so...same brand, same size, same model, same wear. And proper tire rotation is absolutely critical on that system. Rears to the front, fronts to the opposite corners.

If the tires check out, you're going to want to pull that case, and open it up. Have a look at the shift fork and it pads...omegamachine.com sells an upgraded fork that is very worthwhile. Have a look at the range collar...this is where the grinding came from. Once that happens, you'll see it gets pretty chewed up. Replace this with as good a gear as you can get. Check the shift screw...with the upgraded fork, this is often OK to re-use.

Get a seal kit if you want.

Now on to the case halves, this is often the root cause...check for ovalling where the shift rail bores are. Have a bushing installed here for general reliability.

 

[deweyville65]

And no one has said a word about the driveline. Check the u-joints.

 

[MagikMan]

Don't shotgun it, I can tell you exactly what you need, cost you between $150-350 depending upon certain wear points. Its an easy R&R, and the bench work is easy as well. And seriously have a look at the tires that could be the problem as well. Circumference must matchb within a quarter inch or so...same brand, same size, same model, same wear. And proper tire rotation is absolutely critical on that system. Rears to the front, fronts to the opposite corners.

If the tires check out, you're going to want to pull that case, and open it up. Have a look at the shift fork and it pads...omegamachine.com sells an upgraded fork that is very worthwhile. Have a look at the range collar...this is where the grinding came from. Once that happens, you'll see it gets pretty chewed up. Replace this with as good a gear as you can get. Check the shift screw...with the upgraded fork, this is often OK to re-use.

Get a seal kit if you want.

Now on to the case halves, this is often the root cause...check for ovalling where the shift rail bores are. Have a bushing installed here for general reliability.

I will check tires this weekend. But I had to buy 2 new tires when I bought the car and used 2 that were on it. Same size but not same mfg. It will be interesting to compare them. .25" is a close tolerance but I will check. April I had to replace the transfer case with what was ported to be a good used. I will take your advise and do the checks. I believe that fixing this transfer case is much better than take a shot at another unknown unit. Thank you for your insight. In regards to u-joints. When I had the transfer case done we checked them, all were good. This was a 'Truck Rescue' and it has been worth it but it is a process that will be on going for awhile. Will post the results of my actions.

 

[ScottT80]

On a V6 Explorer thats a sure sign the transfer case is going out. I've had two that did it.