Older vehicles can be difficult to understand and troubleshoot, especially when the culprit is a loud squealing noise that seems to be emanating from under the hood of a 1.5 ton Chevy Suburban. The plus side is that there are usually some pretty distinct reasons for such a squeak or squeal to come from a Suburban and figuring out what the problem is under the hood is actually as easy as 1,2,3.
Determining if a Belt, Tensioner or Pulley is at Fault for the Suburban Squeak
There are a few different belts under the hood of a Suburban and these are operated using a series of tensioners and pulleys that work in unison to make the components of the vehicle operate effectively, efficiently and most of all quietly-that is until one of these belts, tensioners or pulleys goes bad! The most common belt that can cause squealing on a Chevy Suburban is a serpentine belt. This is a good starting point to determine if a belt is at fault for the squeak because the serpentine belt is relatively cheap (about $25) and easy to replace.
To determine if a pulley or tensioner is at fault for the loud noises that are coming from under the hood of the vehicle check each pulley or tensioner individually. This can be done (in many cases) by listening to the sound that is made when the vehicle is running and determining where the squealing is coming from. The most common places for a squeaky tensioner or pulley on a Chevy Suburban are the idler pulley and the belt tensioner for the Serpentine belt which can be found near the top of the engine. A Cheggs manual can help when it comes to determining where the pulleys, tensioners and belts are as well as how to replace the various components of these parts.
Determining if a Water Pump is at Fault for the Suburban Squeaking Sounds
Another common reason for a loud squeal or squeak coming from under the hood of a Chevy Suburban is the water pump. Sometimes a water pump will begin to make warning sounds a few thousand miles before it actually goes bad. If a squeak or squeal is coming from the area under the hood near the water pump and it is a short and noticeable squeak then there’s a chance that the water pump is going bad. Typically this is a warning sound that will come prior to any other signs that the pump is having troubles or on its last leg but in some cases the squeal will accompany a drip of coolant from the weep hole of the pump which signifies a serious need to replace the faulty water pump on the Chevy Suburban immediately. (Remember, a Suburban is a very heavy vehicle so you probably don’t want to be pushing it anywhere any time soon)
Determining if a Bearing is at Fault for the Suburban Squeak
Finally, another very common reason for a squeaking sound under the hood of a Chevy is a faulty bearing. The pulleys that run the belts under the hood for the water pump, alternator and various other components of the vehicle all have bearings. If the bearings lose grease or begin to go bad they could make a series of sounds including grinding noises or in some cases squeaks and squeals. On older model vehicles it is possible (sometimes) to replace just a bearing but in most cases the entire pulley will have to be replaced if it is the reason for the squeak. In order to determine if a pulley is at fault for the Suburban making the loud noises simply spin the pulley manually while under the hood to determine if the flow of motion is smooth and quiet or if there is a noise that comes from the movement. Remember that the noise that is heard from a manual spin of the pulley will not be near as loud as that coming from the actual running of the motor because the belt will not be running along the pulley nearly as fast.