Van sounds like leaf blower

possible cv joint failure

Humming Noise Front End- Any Ideas? - Ford Explorer and Ranger ...

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Dec 18, 2008 - 19 posts - ‎16 authors
Have a 98- Eddie 4.0 SOHC, 4WD with a 100,000 mi. When driving it has a humming noise, it almost sounds like a bad tire, or a ... I start to hear the humming noise at 20 mph, it is very loud at 40 to 50 mph ... 94 XLT-95 FX4. humming gets louder as speed increases
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That could be anything - from tire noise to bearing noise to the passenger in the rear seat! Where does the noise seem to be coming from - front? rear? left? right? engine? Is there anytime that the noise changes or goes away? Gets louder or softer? All these things help us to help you. Year and engine size are helpful too.

there can be a crack on exhaust manifold or on eghaust muffler.

"Loud humming" could describe many of the noises that your minivan may make. Let's start with the basics: do you hear the noise only when the van is in motion or also when the van is stopped? If you can hear the noise even when the van isn't moving, you're most likely looking at something in the engine compartment. Your serpentine belt and the alternator bearings (and, to a lesser likelihood, your power steering pump) are all sources of noise "in there." An A/C compressor on its last legs may also vibrate and cause a humming sound, though that's usually described as more of a "growl."

If you can only hear the noise when the car is in motion, the next question is whether it changes pitch/volume due to engine speed or due to road speed? For example, does the noise get quieter (momentarily, perhaps) when the transmission shifts gears? Or, does the noise simply get louder/change characteristics in a linear way as the van gets faster and/or slower?

Depending on the mileage on your van, the transmissions have been known to get quite noisy after a while, especially if you are doing sustained high-speed driving. The solution for that particular problem isn't cheap, as it involves replacing or rebuilding the transmission (the shift bands may be fine; the noise is caused by bearing wear, seal failure, and other sundry issues that still require pulling the transmission). A less expensive problem is that you might have a problem with one of your tires--a tire with separating belts may make a noise like this as it slowly tears itself apart. If you hit something hard with the undercarriage of the van, you might have a drive shaft that's slightly bent and hence is causing some sympathetic vibrations in the car because it's out of balance.

Depending on the cause, your humming sound may be one of those things that comes with driving an older car--or it may be a sign of the imminent failure of something serious. It's worth getting things checked out again to try to find the cause of the problem. You'll feel a lot better knowing what it is, even if it's something you choose not to fix.

swirl cage on blower motor is out of balance replace swirl cage hope this helps

Misalignment of the belt, incorrect belt, worn or loose tensioner, Too tight of an adjustment (many service centers do this on purpose so when the belt breaks in it becomes properly adjusted, I do not believe in this philosophy), The belt is actually one long belt called a serpentine belt.....

Could be either a loose belt or you are low on power steering fluid,or the power steering pump could just be worn out.

almost sounds like something is in it and it is located on passenger side under dash.