I have a 99 Ford Windstar that I just bought from a friend. We had to replace the starter before driving it bc it sat for a long time. The squealing sound happens as I drive and does stop the more I drive the vehicle. What could this be? Does the serpentine belt needs to be replaced or can I just adjust it?

  • Does the squealing sound happen when the engine is running but you are not driving? Is the sound coming from the engine area? Have you isolated it to the serpentine belt?
    – CharlieRB
    Mar 31, 2017 at 13:51
  • No only when I am driving does the squealing sound. I haven't isolated it I am trying to find out if that is the issue. I just got the vehicle and it didn't make the noise yesterday when driving but this morning while taking daughter to school I noticed it. R there other things it could be? Mar 31, 2017 at 13:57
  • Is the squealing related to engine speed? In other words, does it increase as you step on the gas pedal? Or is it more related to the speed of the vehicle regardless of how you are pressing on the gas pedal (does it stay the same if you let off the gas)?
    – CharlieRB
    Mar 31, 2017 at 14:00
  • No it happens more as I press on the gas. And when i come to a stop the sound decreases. But after running for awhile it tends to decrease in sound Mar 31, 2017 at 14:06
  • Thanks for clarification. I would take Paulster2's advice then.
    – CharlieRB
    Mar 31, 2017 at 14:49

2 Answers 2


You could start by changing the serpentine belt. Your Windstar has a self adjusting tensioner, so it could be this also, but there's no way to adjust it independently of changing it. You can check to see if it's doing it's job by running the engine and seeing if the belt has a lot of flop (not sure how to describe this) when you rev then quickly release the throttle. When the engine spins down after a quick "blip" of the throttle, you shouldn't see much in the way of the belt vibrating. Where to look for this is the longest stretch of the belt between two pulleys, usually just after the crankshaft pulley (large pulley at the bottom). Most engines rotate in a clockwise motion. The crankshaft pulley is where the power comes from, so the slack to the backside (before the crankshaft pulley) is most likely going to be tight all the time. It's after the crankshaft pulley where you're going to see any type of slop occur in the belt. If the tensioner spring cannot keep up with the revs of the engine, it will allow the belt to bobble and it could lose traction, causing the squealing issues you talk about (yes, this is a long winded answer).

It could also be that the battery just needs some TLC (recharging). If it has sat for a while, it could have been discharged quite a bit and still needs some recharging. Right after you start the vehicle, the battery has done it's job, but needs to replace the energy it used to get the engine started. A combination of weakened battery and tired belt could easily account for this. You can check your battery by putting a multimeter onto it and checking the voltage without the engine running. If it's in the 12.5-13.2vdc range, it should be in good shape. If it's below this, try putting it on a battery charger overnight on the lowest Amperage setting there is (2A is good for this).

Really, I think the answer here is the belt. Once you get it changed you'll probably find the squealing will have disappeared.

  • When I bought the van there was no battery in it which I didn't know. So I had a brand new battery from a Kia Optima that we put in it. Could that cause a problem. And the squealing is only when I am driving the van. It is less noticable the more I drive Mar 31, 2017 at 13:55
  • @DianeVGarber - I doubt the battery is causing your issue. I'd bet the belt is just old. Even if it isn't completely bad, it could probably stood to be changed as when they sit the rubber can get hard and not want to hold to the pulleys as well. A belt is a relatively cheap maintenance item and a good place to start in your case. Mar 31, 2017 at 13:57
  • Thank U will check that and get back to let know how it went. Thank u for the insight Mar 31, 2017 at 14:00
  • Sorry to ask another question. R u talking about the serpentine belt?? I am looking for the part. Or is the timing belt? How can I tell which one it is?? Mar 31, 2017 at 14:03
  • @DianeVGarber - Serpentine belt. Mar 31, 2017 at 14:20

It really sounds like a wheel bearing. The noise would get louder the faster you drive up to the point where you can't hear it anymore because it is too high pitched.

If the squealing doesn't happen while you are stopped with the engine running, then the issue isn't the belt or tensioner. If the problem were either of those, it would be constant, moving or not.

You want to check this before driving at speed, because, you could really mess up the vehicle if the wrong thing breaks. Breaking it while moving always costs more. For instance a seized wheel bearing can cause parts to be bent which would ordinarily be fine.

The safest way to check where the noise is is coming from is to have someone walk or bicycle along side you while you drive slowly on a non-main street. Let them know you plan on steering to the left and right to check if the noise changes when turning the wheel. They should be able to tell you where the noise is coming from. It is more difficult to tell from inside even if you have all the windows down, though you may be able to tell which side that way.

Whether or not you can replace it at home easily depends on if the wheel bearing is pressed into the control assembly or rear hub. This is a part that's probably not dealer only.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .