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Transmission Problem Diagnosis With This Simple Tool

Have you ever heard a noise coming from somewhere in your car that you can hear, but the service center mechanic you went to cannot? This can be a problem if your transmission is still under warranty, but the mechanic denies there is any detectable problem. Here’s a simple tool to solve this problem that can be especially useful for diagnosing transmission problems and other vehicle noise maladies.


Pinpointing Vehicle Noise

One of the oldest and simplest tools used for pinpointing noise coming from a vehicle is the trusty mechanics’ stethoscope. Trying to find the source of a ticking, rattling or hissing can be difficult by ear alone under the hood of a running engine, which is made definitely easier using a mechanics’ stethoscope.

But what if that strange sound is coming from somewhere else in your car that you cannot reach with a stethoscope and/or occurs only when you are behind the wheel? And worse yet, no one else seems to be able to hear the noise except for you?

You are not alone with this problem as there are multiple reasons for this phenomenon, which can be due just to the fact you are the owner of the car and particularly attuned to noticing when something does not sound right in your vehicle. In addition, years spent around noisy engines takes its toll on a mechanic’s sense of hearing.

The Code Reader Mechanic

However, what makes this problem especial is the common complaint that many mechanics at dealerships are just diagnostic code readers because the dealership doesn't care to train their employees on the fine art of troubleshooting a car’s problems. Electronic diagnostic tools are extremely useful---and expensive---but some would argue they can become a crutch when it comes to finding the cause of a problem and its prognosis.

Another particularity of this problem is the argument that dealerships are more prone to sell you a new vehicle rather than help you fix your old one---especially if your vehicle is near the end of its warranty period.

So, how can you argue that you know something is amiss when the dealership or service center says that their equipment detects no malfunctions in something as critical as your transmission? The answer to this is surprising simple and inexpensive.

If You Hear This, Your Transmission is Bad

A recent video from the Scotty Kilmer YouTube channel addresses this noise detection problem with an affordable “Noise Master” piece of test equipment sold online for under $100 that is available under a few different brand/model names.

The basic function of this piece of test equipment is to easily pinpoint troubling noises that cannot be duplicated in a repair stall and only occur during road driving. Typically, it is a multi-channel device with up to six microphones that you can position anywhere under the chassis of a moving vehicle to pinpoint a noise's source and thereby aid in its diagnosis and repair. Headphones and a LED display indicate when noise is detected relative to the placement of the microphones.

To show you how this works, here is Scotty’s explanation of how useful this piece of equipment is, demonstrated in the first 5 minutes of the following video:

And finally…

For more transmission-related articles, here's how you can change your transmission fluid without removing the pan; and, how servicing your vehicle’s automatic transmission can be a DIY project that saves you money.

Plus, a popular article about The Sealed Automatic Transmission Flush Deception revealed by another YouTube mechanic.

COMING UP NEXT: Where to look under the hood for two common car repair scams.

Timothy Boyer is Torque News automotive reporter based in Cincinnati. Experienced with early car restorations, he regularly restores older vehicles with engine modifications for improved performance. Follow Tim on Twitter at @TimBoyerWrites for daily automotive-related news.