humming gets louder as speed increases

[koenig65]

well a couple of days ago I happened to drive my wifes 1998 Limited,5L AWD.
Any way it seemed much louder than normal and as the speed increased the noise got even louder. She said its been like that for a while, maybe a week or two......Women?????
I jacked up the truck and checked the front wheels,there is absolutely no play at all so that leeds me to think its not the wheel hub bearings. I noticed some cupping on the tires though. I already had some new tires i had bought a few months back, so I had them swapped but the noise did not change.. what should I check next....should I get a wheel alignment? I donot feel good about letting my wife drive around with the kids in the truck till I get this solved.Any sugesstions would be appreciated...Thanks

 

[Northern]

You're sure the location of the humming is coming from the front?

 

[koenig65]

no but its hard to tell from inside. I'm gonna get someone to drive by me and see if I can tell. i thought it was the passenger side but my buddy was sure it was the driver....go figure

 

[koenig65]

can"t tell when the truck drives by me but when you turn to the right at speed the sound goes away???????

 

[Northern]

Have you carefully let go of the steering wheel while on a flat and straight strench of road to see if it pulls one direction or another? If it pulls to either direction, that can be an indication that you need a wheel alignment.

One thing that comes to mind is gears. When the gears in the rear-end were almost shot in my 1998 F-150, it produced a howling noise. Also, in a 1992 Mustang I had owned, the rear-end had leaked all the fluid out and caused a humming noise that I couldn't pinpoint until I saw the oily dust that had collected. Could it be anything like that?

 

[storlied]

I have the humming/whining also, I've had it for over a year I'm sure.. it has gotten worse a select few times I was hard on my truck. I'm 90% sure it's the front diff letting you know it's wearing down. It's not an imediate danger but it should be taken care of sooner or later to prevent complete failure. If you're that worried about it, and the roads are nice.. you could always drop the front driveshaft to decrease the load on it. But then you'd have to apply and parking brake everytime you park so it slowly doesn't roll away, which is a risk in itself because a sudden change like that... Someone is gonna forget to put it on, or take it off.. which will lead to either a truck that's moved a few inches after you get outta the store [if you're on a slope] or completely burnt up parking brake pads.

You should search for the AWD parking drift thread.. it's not as bad as it seems.. the vehicle will move.. but extremely slowly. [with the front driveshaft removed]

 

[luckyfrye]

dont know recently had the same issue, it ended up being several little things id say start with the belt tensioner most of my noise came from there oh and a crappy altinator.

 

[luckyfrye]

or a loose radiator gaurd also cause a slight humming noise

 

[storlied]

You have a 1st gen, different setup... this noise is common for our model. I'm pretty sure I know exactly what he's talking about. The noise is dependant on speed, correct? Not engine rpm?

 

[koenig65]

your right no matter the gear its totally dependant on the speed of the truck....example if i"m doing 60 kms in drive and take the OD off rpm's jump but no change in noise...

 

[1999_sport]

wheel bearings are probably gone, mine would hum, as i started to accelerate and would stay pretty consistent after 80 km/h, usually the noise will get softer or go away when you turn corners, letting you know what side it would be, unless there both bad

 

[koenig65]

1999 sport ......rear wheel bearings I asume your talkin about because the fronts seem fine.....correct?

 

[coled43]

It sounds like it has to be a front hub bearing. You may not detect play in the wheel, but maybe some drag when spinning the wheel. I would concentrate my efforts there.

 

[gbranh]

I just went through this on our 2002, right rear. Wheel bearing.

Greg

 

[1999_sport]

1999 sport ......rear wheel bearings I asume your talkin about because the fronts seem fine.....correct?

yes sir, could be front tho, cause you said when you turn the noise goes away, because your basically unloading that bearing, so check them all just in case, and if you find one thats bad you might as well replace the other side, because the other one probably isn't too far behind, quick test grab the tire at 9 and 3, and see if you can move it back and forth, if you can it's usually the broken one

 

[koenig65]

Ok thanks will check the wheal bearings tomorrow..I checked the frontand they had no play so I will jack up the back and check them first...Thanks again

 

[madbrad104]

Ok thanks will check the wheal bearings tomorrow..I checked the frontand they had no play so I will jack up the back and check them first...Thanks again

common problem on my 98 explorer is front driveshaft goes out makes a growling noise on acceleration replaced it 3 times now 50. dollars at scrapyard
wheel bearings go out alot to on my 2nd set of those lol
you can't check play in the wheel bearings ! on the vehicle you can only check upper and lower ball joints by wiggling the tire back and forth even then you need a pry bar and another person to help
madbrad

 

[storlied]

If it's bad enough, yes you can. I've done this, you can actually see the play in the hub assembly when they start to go out if you move the tire. And trust me, let it go long enough.. you could probably fit your hand in the amount of play, very dangerous. [talking about the front hub assembly 2nd gen btw]

 

[luckyfrye]

Overheater

Wtf overheating again, not the thermo or the pump and it only happens when going up hill for a long stretchs

 

[miguelv02]

2003 Ford Explorer 4.0 4AWD I change the wheel bearing hub driver and passenger side and still doing that noise, humming, can any one tell me what it is...
Thanks;
Miguel