95 Exploder: Vibration/Hum from front end...

Hi all,

I have a '95 Exploder which I recently purchased about 2 weeks ago. Since that time I have been plagued with a vibration/hum from the front end that gets louder/worse as I increase in speed. The problem becomes noticable when I reach speeds of approx. 45mph and steadily increases in volume and in speed as I accelerate. perfect way to describe what it sounds like is a "Jake Brake" but not in volume...its not loud at all, its just there, whether I keep it in drive at 60mph, or even if I shift into neutral, its there.

Now I have already ruled out several things, which are:

its not anything in the drivetrain ( tranny, transfer case, drive shaft ) as I had all inspected and all passed ( front/rear shafts were balance tested, tranny is in perfect condition as well as transfer case. I replaced all of the universal joints anyways just to be sure )

its not tire balance ( had tires checked and rechecked and speed balanced twice, and rims are perfect, no signs of warpage )

its nothing with the braking components ( rotors are fine, no binding, nothing out of round, calipers are new and mounted firmly to thier designated positions )

its not the hub bearings ( they are fairly new with absolutely no signs of wear, smooth fluid movement, no play )

its not the front differential itself ( previous owners replaced it with a new unit straight from ford, everything checked perfect )

So now I'm left to figure out if I have a bad half shaft ( vibration/hum *feels* like it comes from passenger side while driving, but passengers in truck say it *feels* like its on the drivers side ) But I have had both shafts checked and both appear to be in excellent shape. Only thing I can think of is that one may be slightly unbalanced, which would require me to remove them and have them checked.

There is one thing about the vibration/hum that is strange, when driving on a road where there are slight peaks and valleys in the pavement, as the truck rises and settles on its suspension during driving, the vibration/hum dissappears for the split second that the trucks suspension is reacting to the roadway. thats why I'm thinking I may have a bad half shaft.

Any input on this little problem would be much appreciated, as I'm left to scratch my head and say WTF is wrong with this Exploder.

Any unusual tire wear? I had exactly the same symptoms with my '95 Explorer. The tread was wearing in an irregular pattern on the inside of the front tires. I replaced the tires & shocks, and the noise is gone.

Any unusual tire wear? I had exactly the same symptoms with my '95 Explorer. The tread was wearing in an irregular pattern on the inside of the front tires. I replaced the tires & shocks, and the noise is gone.

Hmmm...now that I think about it, the previous owner had rotated the front tires to the back, and those do show some wear on the inside edge of the tire, what I have also noticed is that both front tires are pitched inward toward the top, indicating that an aligment may be needed...again...

I notice though most explorers rougly the same year look all the same, the front tires all seem to lean in toward the top, so i'm not sure if ford designed the suspension in a way that requires the wheels to sit at that slight angle...which eventually will wear out the inner edge...pretty dumb if they did.

I'll have to look into this further...i'm going to drop my tire pressure down to see if the vib/hum stops or lessens any, the lesser pressure should compensate temporarily if the treads are indeed wearing uneven..at least to know for sure. I was planning on buying 4 new tires soon anyways...