1996 Chevy G10 Van, Loud Intermitten Squealing / Groaning

Question

I have a 1996 G10 van with approximately 143,000 miles. The van occasionally makes a very loud squealing or high-pitched groaning noise. One of the difficulties lies in the lack of predictability or consistency of the noise. It only occurs at low speeds. It seems to occur regardless of whether or not I am applying the brakes. It does not appear as if I have to necessarily be turning the steering wheel either. While the noise seems far more common in reverse, I believe it also occurs in drive. The noise seems to occur almost exclusively when I am either parking (even if it is just on the side of the street) or pulling out of a parking space. However, it does not occur all the time when performing these options.

The noise seems to occur far more frequently after the van has been driven for a while. For example, I do not usually hear it when I am leaving my house to go to work, nor leaving work to head home. However, I do hear it occasionally when I am parking at work (after having driven from my apartment), and, more frequently, when returning home.

This van is a relatively new purchase. I have had the rotors turned and front brakes replaced. I do not recall hearing the noise until after the brakes were replaced, though I could be mistaken. I lubed the chassis (as that was one of my initial guesses), but it did not resolve the issue. However, I certainly could have missed a fitting as this was my first time doing it. I had my sister take it to a shop. They did not notice a noise, but said the brake caliper was sticking slightly.

The noise is hard to describe. I suppose is less of squeal or squeak, and more of loud, but high-pitched groan. It does not appear to be coming from the engine or engine bay, but somewhere in the suspension or braking systems.

Thanks.

Answer 1

Judging from the length of the noise (15 seconds), and the fact that a 15-second long noise certainly cannot come from the suspension, I will suggest that your assumption of it not coming from the engine bay is incorrect. Simply said, there is no other place it can come from.

I would say some belt is just loose and therefore is squealing. As preventative maintenance, do replace all of the belts if you don't know when they were last replaced. The belt squeal is not fatal, but it will annoy you and also if an accessory belt breaks while driving, you will lose the features of that particular accessory. This feature (e.g. charging the battery) can be very important.

If the car has a timing belt, and you don't know when it was last changed, now would be a good time for timing belt service, as replacing the other belts means the timing belt is somewhat easier to access with the belts off. In an interference engine (most engines today are of this type), if there's a timing belt and it breaks, you can generally expect expensive engine damage (exception: if you're very lucky, a SOHC engine with 2 valves per cylinder may work after timing belt breaks, even if it's an interference engine). It's much cheaper to replace the timing belt at periodic intervals.