1. Visual Inspection:
* Fluid Level: Check the power steering fluid level. Low fluid can cause similar symptoms to a failing pump. Top it off if needed with the correct type of fluid (check your owner's manual).
* Fluid Condition: Inspect the fluid for discoloration (brown or burnt smell indicates overheating and potential problems). Metallic particles in the fluid point towards internal pump damage.
* Leaks: Look carefully for leaks around the pump, hoses, and connections. A significant leak will obviously reduce the system pressure.
* Belt Tension and Condition: Ensure the serpentine belt (or whatever drives your pump) is properly tensioned and not cracked or worn. A slipping belt will reduce pump function.
2. Listening for Noises:
Start the engine and listen for unusual noises coming from the power steering pump. Whining, groaning, or squealing noises often indicate bearing wear or internal damage within the pump.
3. Fluid Pressure Test (Most Definitive, Requires Tools):
This is the most accurate test but requires specialized tools. You'll need a power steering pressure gauge. The procedure involves connecting the gauge to the pressure port on the pump (location varies by vehicle; consult a repair manual). With the engine running, you'll check the pressure readings at idle and under load (turning the steering wheel). A repair manual for your truck should give you the correct pressure specifications. Low pressure consistently indicates a possible pump problem.
4. Steering Wheel Feel Test:
With the engine running, turn the steering wheel from lock to lock. If the steering is extremely stiff or requires excessive effort *even after confirming adequate fluid level*, it suggests a problem in the power steering system; however, this doesn't isolate the pump as the sole cause. Other potential culprits include:
* Low fluid (already checked above)
* Faulty power steering rack and pinion
* Clogged lines or a restricted filter
* Leaks in the system
Important Considerations:
* Safety First: Always disconnect the negative battery terminal before working on any part of the power steering system. Power steering fluid is under pressure and can cause injury if released unexpectedly.
* Repair Manual: A repair manual specific to your 1987 Dodge D150 is highly recommended. It will provide detailed diagrams, specifications, and procedures for testing and replacing the power steering pump.
* Professional Diagnosis: If you're not comfortable performing these tests or are unsure about the results, it's always best to take your truck to a qualified mechanic for a professional diagnosis. Misdiagnosing the problem can lead to unnecessary repairs.
By systematically performing these tests, you can get a better idea of whether your power steering pump needs replacing. Remember that several factors can cause power steering issues, and the pump may not be the sole problem.
