Questions and Answers
Why Does A Ford Explorer Hum?
Q. I have an automatic trans. 1997 AWD Ford Explorer 5.0 liter V-8 with ABS, P/S, A/C, cruise control, rack and pinion and 123,000+ miles. I took it to a Tire and Muffler specialist shop to have the tires rotated and balanced, wheel alignment and oil change. I was called back shortly after leaving it with the suggestion that two of the tires be replaced as they were very worn.
The tires that were on the truck were Delta (Del-Nat Tire Corp.) 235/75R15 with about two years of highway driving (commuting) wear on them. Also, they remarked that the front ball joints should be replaced. Since I could agree that the front tires were probably pretty worn, I agreed. They were going to replace with two brand new Dunlop Rover Owl 235/75R15.
I got the truck back and about 15 to 20 minutes after getting on an open road and getting to about 70 mph, I noticed a low intermittent (in and out) humming noise, apparently being generated from the front end. I took it back to the shop two days later and explained the issue to the technician and left the car.
The next day they called me back to say they heard the noise and diagnosed, but that they could not pinpoint the issue and assured that nothing of the work that they did to the car could have caused it. They did, however, say that the problem could potentially be something in or part of the transmission.
Now, to remain unbiased in your response that I hopefully can get to my questions, I will leave out what I think the problem was and what eventually another place pinpointed the problem to be. This is really a second opinion type scenario that will assist in substantiating by point of view.
Taking into consideration all of the factors that I described above, the questions are:
- What is the cause of the problem or problems? What is/are the problem(s) that is/are causing the noise?
- What other parts/systems of the truck could this problem potentially effect/damage?
- Could at least the beginnings of this problem have become apparent within the short amount of time after driving the car at high speeds for an extended period of time?
- Should an accredited tire and muffler specialist who has been in business for 40 years been aware of what could have caused this problem?
Any help in corroborating my belief would be greatly appreciated.
A. Since I can not drive the vehicle and experience the symptoms first hand, and they can, I am at a distinct disadvantage. You also neglected to tell me what kind of transmission you have in the truck. In this venue the best I can do is offer the most likely causes of a particular problem. If you bring it into my shop and let me drive it, I can be much more accurate.
I can think of several things that can cause a noise such as you describe, it could be coming from the engine, intake or exhaust, power steering or the drive line. It could as lo be wind or tire noise. Even a change of the material used in the road surface can cause it.
If it is an intermittent noise I would say the most likely cause of the problem is in the power steering system. A power steering pump starting to go bad could make a humming type noise.
Actually, you would have been better off telling me what they said was the problem and based on that I could be more informative. Other than that this is just a glorified guessing game.