Diagnosing transmissions

Diagnosing today’s complex transmissions

Though they may be trying their best to do consumers a good service, transmission professional who do quote prices for major repair over the telephone are doing just the opposite.

First, even qualified automotive technicians who specialize in other areas of the car seldom have the ability to observe and then relate all the information necessary to come to an accurate conclusion related to transmissions. Then, there is the ever constant problem of conveying their observations in a manner that is meaningful to the transmission specialist. For example, will one’s definition of the terms slip, squeak, grind, squeal and bump be the same as the transmission professional who is trying to interpret those terms? Categorically—no!

Next, have all the complicated diagnostic procedures been performed which are necessary to provide a correct and cost efficient repair recommendation? The odds are poor at very best. With today’s sophisticated, electronically controlled transmissions, in many cases accurate diagnosis requires “high tech”, expensive diagnostic test equipment before even the professional can render a qualified opinion.

Further, when it has been determined which system(s) in the transmission have failed, then the extent of the internal damage must be determined before a meaningful price can be discussed. Short of performing these essential diagnostic procedures, persons who quote prices are either guessing, with virtually thousands of variables or stating a meaningless price which will have to be adjusted when all the diagnostic data is obtained.
We could compare this situation to a patient who calls his dentist, describing oral pain under a given set of circumstances.

Is the pain caused by a gum infection, a cavity, the need for a root canal or is the only remedy complete tooth removal? The average consumer would be less than confident if the dentist were to recommend root canal or extraction with such incomplete information.

The same is true in transmission diagnosis. Any meaningful diagnosis can only be rendered after a complete inspection is performed.
Should you have questions of any nature, please feel free to Call Transmasters. We pleased to assist you.

When you come to a stop does your car stall? While driving down the highway do you feel a shudder? Have you ever tried to pass another car and felt like someone abruptly applied the brakes?

You wouldn’t be alone if you blamed the transmission for causing these problems. In fact, these problems may be due to something else.

We are all aware that late model cars use a computer to control the engine. Many cars use the same computer or another computer which shares the same information, to control the fuel injection, ignition and transmission. Automotive engineers did this in order to achieve more efficiency and better mileage. This means that your engine and transmission are connected together in more ways than just simply being bolted to one another.
Since the engine and transmission are controlled and work together, they are referred to as a ‘Powertrain.”

Consider that shudder you felt cruising down the highway. The computer is using sensors on the engine and transmission to detect such things as throttle position, vehicle speed, transmission input speed, stop light switch position, etc.

As you drive the car, you are constantly changing the demands on the powertrain (i.e. acceleration, cruising, passing, coasting and idling). The computer recognizes this by monitoring various sensors. To improve fuel economy, the computer will (under the right conditions) engage a clutch inside the torque converter.

NOTE: The torque converter is a device located between the engine and transmission. It is filled with hydraulic oil (automatic transmission fluid). The hydraulic oil coupled with the design of the torque converter allows the engine to run slowly at an idle (like being disconnected) with the vehicle stopped. At higher engine speed, torque is transferred through the hydraulic oil to the transmission.

Without special equipment and experience, no one can tell if a shudder is caused by something slipping inside the transmission, the torque converter, a weak spark, a dirty fuel injector or a loose electrical connection. Your Automatic Transmission Rebuilders Association (ATRA) transmission specialist is a highly qualified professional and can best determine what, if anything your transmission needs.

Should you have questions of any nature, please feel free to contact your local ATRA Member. They will be pleased to assist you.