* Low Power Steering Fluid: This is the most common cause. Low fluid causes the pump to work harder, leading to cavitation (formation of air bubbles) and a growling sound. Check your fluid level immediately. It should be at or near the "full" mark on the reservoir. If it's low, top it off with the correct type of power steering fluid (check your owner's manual). A temporary improvement after adding fluid points strongly to this as the culprit.
* Worn Power Steering Pump: The pump itself might be wearing out. Internal components like bearings or gears can wear down, creating friction and the growling sound. This is a more serious issue requiring pump replacement.
* Worn Power Steering Pump Pulley: The pulley that drives the pump can wear out, become misaligned, or develop play. This can lead to uneven load on the pump and create a growling noise.
* Worn Power Steering Belt: A worn, slipping, or misaligned serpentine belt can cause the power steering pump to work harder and produce a growling sound. Inspect the belt for cracks, fraying, or glazing. Check for proper tension as well.
* Clogged Power Steering Lines or Filter: Restricted fluid flow due to clogged lines or a dirty filter increases the pump's workload, potentially leading to a growling noise. This is less common but possible.
* Internal Pump Leak: A leak inside the pump can introduce air into the system, causing cavitation and a growling sound.
Troubleshooting Steps:
1. Check the power steering fluid level: This is the first and easiest thing to do.
2. Inspect the power steering belt: Look for wear, cracks, or slippage.
3. Listen carefully to the noise: Try to pinpoint the location of the noise. If it's definitely coming from the pump area, the problem is more likely to be within the pump itself or its related components.
4. Turn the steering wheel slowly from lock to lock: Listen for the sound at various steering angles. This might help identify if the noise is related to specific steering positions.
If the growling persists after checking and topping off the fluid, it's best to take your van to a qualified mechanic for diagnosis and repair. Ignoring a growling power steering pump can lead to complete pump failure and potentially damage other components in the system.
