Auto Service World
Feature   May 1, 2012   by Tom Venetis, Editor

Transmission Work Gets Complicated

Modern electronics means transmission servicing requires complex diagnostic work

Transmission work remains a staple of automotive repair. Changing vehicle technologies and the changing automotive sales landscape, however, means challenges for independents looking to continue to offer transmission services as a significant part of their operations.

The most significant change service shops are seeing right now is how complex electronics have moved transmission operations from being purely a mechanical-only process.

James Blunt, shop foreman with Stan’s Transmission Centre Ltd. in Vancouver with fifteen years of experience in transmission diagnostics and repair, says while the basic principles of transmission operations are the same from when he started, the difference is “now you have a computer controlling things instead of your foot (controlling it) through the gas pedal.” For a shop like Stan’s Transmission Centre, one in operation since 1964 and specializing in transmission work, this electronic reality means a heavy investment in new diagnostic equipment and training.

“Where fifteen or twenty years ago, you could figure out pretty quickly if a kick-down cable, shifter cable or modulator was the problem, now the advanced vehicle electronics means you have to do a complete diagnostic examination,” says Dan Fenos, owner of the Toronto-based Transmission Depot. In fact, the first step in transmission work must be a complete electronic diagnostic to eliminate the possibility that a transmission problem is not really a problem with a faulty electronic module or solenoid required for the operation of the transmission.

“Today’s electronics play a big role in transmission operations and if you have an electronic failure somewhere, it can quickly damage a transmission,” he adds.

Tony Stevkov, operations specialist with Mr. Transmission agrees that today’s vehicle electronics have moved transmission repair and maintenance out of the realm of mechanical-only work. This means technicians have to take a broader range of training to be up-to-speed on the work required for transmission servicing today.

Let’s take one example of the kind of knowledge a service technician is going to need today. In a recent Automatic Transmission Service Group Technical Manual (, the complexity of the Mitsubishi F5A5A and Hyundai/Kia A5GF1 transmissions are outlined, pointing out that the five-speed front-wheel drive transaxle is fully electronically controlled for upshifts and downshifts. Individual gear ratios are achieved through three planetary gear sets and there are three different planetary gear ratios. As well, to help improve fuel economy, the torque converter clutch is controlled by the PCM, depending on throttle position, transaxle temperature and speed. In a further note, just to add to the complexity mix, the Mitsubishi system uses a four-speed valve body with an added solenoid to control reduction band, “so there are six solenoids instead of five. The Low/Reverse solenoid is now a double-duty solenoid and used to also apply the added direct clutch pack, based on the position of the switch valve in the valve body.”

Because all of the complex electronics, the service technician will also have to be prepared to hunt down other electrical problems that could be causing transmission problems. The Automatic Transmission Repair Association ( points out that something as simple as a bad battery connection can cause the transmission solenoids to operate improperly.

Bob Maderic, owner of Automatic Transmission says these technical challenges means he spends a lot of time and funds keeping his technicians trained and up-to-date on the latest vehicle technologies. This is especially important as his shop specializes in transmission work on foreign vehicles, such as BMW, often handling in-warranty work that the dealerships send his way.

“It is very hard today to find the right kind of staff,” he adds. “In our niche, the vehicle import market, we have to provide a lot of training and support to make sure our technicians can do the work. I’ve taken courses in Germany to understand how those transmissions work.”

If the technical challenges are not daunting enough, there is another that will be: selling transmission service. Why should that be so difficult? Maderic says today’s shops have only to look across the road to the new vehicle sales offices and see cars being offered with incredibly low financing options and with powertrain warranties of 10 years. This makes it difficult to convince an owner of an older vehicle that with the depreciation the transmission repair is worth the cost. If a 2001 Ford Windstar comes in with transmission problems the work on that vehicle can be over $2,000. “But the car is not worth that much,” says Maderic. “Not even for scrap.” What a service writer and technician will have to assess is if the vehicle owner still believes there is value in that vehicle. If the owner has spent the time and dollars to maintain it, “then the investment in a transmission rebuild is a good investment.”

Mr. Transmission’s Stevkov adds that even with the cost of a transmission rebuild, it is in fact less expensive than purchasing a new vehicle even with today’s low-cost financing advertised by car makers.

“One thing we try to explain to customers is that while it seems to be a low monthly payment initially (on a new vehicle), you do have to put a down payment, there will be maintenance and repairs to be paid for,” Stevkov adds. “Repairing a vehicle is a one-time thing … and one thing people have to remember is not every vehicle needs a complete transmission overhaul. Some can be repaired with minor fixes, such as replacing a throttle positioning sensor.”

Stan’s Transmission Centre’s Blunt adds most problems with transmissions can be avoided if vehicle owners follow the recommended service outlined in the owner’s manual, such as regularly having the transmission fluid inspected and the mechanism examined at the intervals specified.

“Even though getting the transmission regularly services might seem expensive, it is much less expensive than having it repaired.”

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