First lets clear up a few misconceptions. The noises do not get louder due to age. Things happen that allow you to hear those noises easier. Door and window weatherstripping shrinks and dries out so they don't seal as well. There's also a rubber strip at the rear edge of the hood that blocks a lot of noise. The biggest thing is the exhaust system. Four years old is way too soon to expect to find rusted parts, but there could be a broken joint. An exhaust leak is the most common thing to hear.
Noisy wheel bearings are also common on all car brands. They will sound like an airplane engine but only when the van is moving.
As for getting "bamboozled with repairs that aren't necessary", that seems to be what everyone assumes with mechanics but with no other profession. That's because we don't trust what we don't understand. You will know if a repair wasn't necessary when it doesn't solve the problem, and your mechanic knows that too. He knows if the noise is still there, he is going to have to justify his diagnosis and remedy.
You, as the driver, have to take some responsibility too. Rather than assuming you're going to be ripped off, or the mechanic is incompetent, the place to start is by providing all the clues and observations possible. All you've said so far is it's loud. That's like saying my pain is worse today than it was yesterday. You have no clue if I have a stomach ache, a hang nail, I cut my foot off with a chain saw, or my ex-girlfriend came back. You need to see if the noise can be heard when the van is standing still with the engine running. Does the pitch change with a change in road speed? Is it louder when accelerating than when coasting? Is there any body damage such as the front edge of a door bulging out and catching wind? If you can't find some things that affect the noise, have a mechanic go on a test-drive with you. We can often tell cause by the sound.
If you went into any repair shop and gave them the description you posted above, you can be sure the first thing they're going to do is ask you the same questions I just did. When you can't answer them, (which does happen on occasion, as in when someone drops off a car for someone else), the mechanic is going to have to drive the car first and hope he hears the same thing the customer is complaining about. Test-drives can take five minutes or an hour, and you're paying for his time by the hour. That's just one of many things that cost people more money than necessary at repair shops. The more information you can provide, the better chance you'll have of getting the problem fixed on the first visit and at a lower cost.
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Thursday, December 13th, 2012 AT 1:02 AM