Automatic Transmissions/Transaxles

Repair & Replacement

A car’s transmission consists of an incredible amount of parts. Each component of the transmission is important. However, each component of a car’s transmission can wear or take damage independently of every other part of the transmission. A transmission repair will replace only the parts needed to get your transmission back up and running.

The main concern with a repair of this nature is it may not solve an underlying issue. The transmission may have too much damage, which can make a small repair akin to a stopgap measure that will only become a problem again sooner than later.

Often, repairs work best when the problem is a surface level issue. If a technician has to disassemble the transmission and all its subassemblies, the process can take more time and cost more as well. When the technician has to dig deep into the transmission to find the problem, a transmission rebuild can become a better option. We always try our best to look out for your interest and make recommendations that will keep your vehicle on the road and agree with your wallet.

Transmission Service

Wisener’s Auto Clinic offers various types of transmission servicing, depending on your car’s needs. Here we explain the 5 most common transmission services.

A transmission service is part of your routine maintenance, just like replacing your engine oil. Here we’ve laid out the different types of transmission services we offer at Wisener’s Auto Clinic, including why they are important and what each service includes.

Automatic Transmission Fluid Exchange:
Transmission gears deliver power from the engine to the drive wheels, shifting automatically to provide the best power and efficiency for your driving speed. A special transmission fluid cools and lubricates the gears. Over time, this fluid degrades, and its lubricant qualities diminish. Changing the fluid at the correct intervals can help prevent premature wear and damage to the transmission.
This service includes;

• Removal of the old transmission fluid and replacing it with new, clean fluid of the grade recommended by your vehicle manufacturer.

Automatic Transmission Drain and Fill:
Automatic transmission fluid lubricates, cools and cleans internal components of the transmission. It also helps to maintain the hydraulic pressure necessary for the transmission to function. The additives in the transmission fluid can be depleted over time.

This service includes:

• removing the transmission fill/drain plug to remove the old automatic transmission fluid
• reinstalling transmission fill/drain plug
• refilling the transmission with new automatic transmission fluid to the proper level

Automatic Transmission Filter Replacement:
The automatic transmission filter helps remove dirt and contaminants from the automatic transmission fluid.
This service includes:

• removing the transmission pan
• removing the old transmission filter and replacing it with a new transmission filter
• removing the old gasket material
• replacing the pan gasket with a new gasket and reinstalling the pan
• refilling the transmission with new automatic transmission fluid to the proper level

Automatic Transmission Fluid Exchange & Filter Replacement:
Automatic transmission fluid lubricates, cools and cleans internal components of the transmission. It also helps to maintain the hydraulic pressure necessary for the transmission to function. The additives in the transmission fluid can be depleted over time.

This service includes:

• changing the fluid in the transmission system, including the torque converter and transmission cooler
• removing the transmission pan
• removing the old transmission filter and replacing it with a new transmission filter
• removing the old gasket material
• replacing the pan gasket with a new gasket and reinstalling the pan
• refilling the transmission with new automatic transmission fluid to the proper level

Manual Transmission Service:
Manual transmission fluid provides lubrication to gears, bearings, shafts, and other internal components. Heat, pressure and friction can slowly breakdown the additives in the manual transmission fluid. In addition, small particles of metal may come off the gears as they wear and these metal particles can mix with the fluid. Fluids can also become contaminated with water.

This service includes;
• draining or evacuating the old manual transmission fluid
• filling the manual transmission fluid with the manufacturer’s recommended type and quantity of new fluid
The net result of all these services is to provide better lubrication, improve the holding ability of the friction components, and reduce heat. This means your transmission works better, longer. Therefor you are less likely to face a major transmission repair.

Wisener’s Auto Clinic offers all of these services, and will be happy to explain the details to you.

Filters and Fluids

As the friction material of a clutch or band begins to apply, there is a brief slipping period. It is during that slipping period that heat is generated that cooks the fluid, friction material wears off and enters the fluid, and the fluid’s molecules are being sheared. The gears also heat the fluid and grind at the fluid’s molecules, as well as contaminate it with metal.

Eventually, the fluid is so ground up, cooked and contaminated that it should be replaced with fresh fluid. It is important for the fluid to be in good condition because it serves to lubricate the components. A quality filter will extend the life of the oil and ensure protection of your valuable transmission components. At Wisner’s Auto Clinic we only use quality oils and filters to make sure your vehicle has a long life.

Transmission Fluid Flush

The benefits of a flush are self-evident: all the old, dirty fluid is replaced with fresh, high-quality fluid.
As a result, your transmission should run cooler and receive maximum protection against wear to clutches, gears and bearings.

It should also shift consistently and crisply since the new fluid will provide the correct frictional properties (old fluid loses its frictional properties over time).  Not only that, but performing a flush helps clean the transmission.

Sludge and other contaminants can accumulate in the fluid due to extreme heat breaking down the fluid. These contaminants circulate throughout the transmission before lodging in the filter.

Before the filter can safely capture the contaminants, however, they can lodge in the narrow fluid passages inside the valve body, leading to poor shift quality. Performing a flush also allows you to use a flush additive to help clean the transmission and more effectively remove accumulated sludge and other contaminants.

Transmission Leaks & Repair

It’s possible to drive your car when its leaking transmission fluid, but it’s probably not a good idea since your vehicle won’t drive as required.

Putting safety into consideration, here are a few factors you need to consider:
A common reason why your vehicle could be leaking is a gap in your transmission system. It’s very hard to narrow this down since it could be a space in the gasket, fluid lines, torque converter, seals or transmission pan. It is therefore advisable to consult the services of a professional mechanic.

It doesn’t matter the amount of fluid leaking, the moment you notice transmission fluid leaking onto your driveway, get the leak fixed immediately. If ignored, the problem could escalate over time, leading to a transmission breakdown. Fixing a small leak is fairly easy compared to a big one.

Seals:  What are Transmission Seals?

The input shaft seal, also called the front transmission seal, prevents fluid from slipping past the input shaft. The input shaft inserts into the torque converter or clutch disk, depending on whether the vehicle is equipped with an automatic or manual transmission.

The output shaft seal, sometimes called the rear transmission seal or driveshaft seal, prevents fluid from escaping where the driveshaft yoke slips into the transmission. Front-wheel drive vehicles have two “rear” transmission seals, one for each axle.

How do Transmission Seals Work?
The seals have two important dimensions, the outside diameter and the inside diameter. A seal with the proper outside diameter fits tightly into the recess on the transmission. The inner diameter of the seal has an interference fit along with a tiny spring to keep it snug against the input shaft or the driveshaft. When the input shaft or the driveshaft is inserted into the transmission, the seal locks fluids inside. The seal is designed to prevent leaks regardless of how fast the input shaft or driveshaft spins.

How are Transmission Seals Made?
Transmission seals are made of rubber and plastic. Some seals are reinforced with steel. Most seals have a very small spring around the inside diameter to help produce an interference fit with either the input or the output shaft.
Manufacturers produce these seals in bulk using heavy, factory grade machinery.

Why do Transmission Seals Fail?
Oxidation causes rubber and plastic seals to lose their flexibility, resulting in cracks and eventual fluid leaks. Transmission seals may fail prematurely, or not seal at all, if they are installed improperly. Bearing wear inside the transmission damages the seals, causing leaks.

What are the Symptoms of Seal Failure?
Automatic transmission fluid (ATF) spots or puddle under the vehicle. ATF is red, reddish, or brown and has a distinctive smell. Gear oil or motor oil spots or puddles under the vehicle. The transmission may slip or make excessive noise as fluid loss accelerates.

What are the Implications of Seal Failure?
If left unchecked a small leak may develop into a large leak. Large leaks may result in damage to the transmission if they are not diagnosed and repaired in a timely manner.

The seals on your vehicle’s transmission are an important part of keeping your drivetrain in good working order. Avoid damage to major components by catching leaks early.

Torque Converters

Torque converters are sealed units; their innards rarely see the light of day, and when they do, they’re still pretty hard to figure out!  Imagine you have two fans facing each other. Turn one fan on, and it will blow air over the blades of the second fan, causing it to spin. But if you hold the second fan still, the first fan will keep right on spinning.

That’s exactly how a torque converter works. One “fan,” called the impeller, is connected to the engine (together with the front cover, it forms the outer shell of the converter). The other fan, the turbine, is connected to the transmission input shaft. Unless the transmission is in neutral or park, any motion of the turbine will move the vehicle.

Instead of using air, the torque converter uses a liquid medium, which cannot be compressed – oil, otherwise known as transmission fluid. Automatic transmission cars use a torque converter. This article will discuss why automatic transmission cars need a torque converter and how a torque converter works.

The torque converter in an automatic transmission serves the same purpose as the clutch in a manual transmission.
The engine needs to be connected to the rear wheels so the vehicle will move, and disconnected so the engine can continue to run when the vehicle is stopped. One way to do this is to use a device that physically connects and disconnects the engine and the transmission – a clutch. Another method is to use some type of fluid coupling, such as a torque converter, which is located between the engine and the transmission.

There are three components inside the very strong housing of the torque converter which work together to transmit power to the transmission:

• Pump
• Turbine
• Stator

The pump inside a torque converter is a type of centrifugal pump. As it spins, fluid is flung to the outside, much as the spin cycle of a washing machine flings water and clothes to the outside of the wash tub. As fluid is flung to the outside, a vacuum is created that draws more fluid in at the center.

The fluid then enters the blades of the turbine, which is connected to the transmission (the spline in the middle is where it connects to the transmission.) The turbine causes the transmission to spin, which basically moves your car. The blades of the turbine are curved so that the fluid, which enters the turbine from the outside, has to change direction before it exits the center of the turbine. It is this directional change that causes the turbine to spin.
As the turbine causes the fluid to change direction, the fluid causes the turbine to spin.

The fluid exits the turbine at the center, moving in a different direction than when it entered. The fluid exits the turbine moving opposite the direction that the pump (and engine) are turning. If the fluid were allowed to hit the pump, it would slow the engine down, wasting power. This is why a torque converter has a stator.

The stator resides in the very center of the torque converter. Its job is to redirect the fluid returning from the turbine before it hits the pump again. This dramatically increases the efficiency of the torque converter.

In brief, the torque converter is a type of fluid coupling, which allows the engine to spin somewhat independently of the transmission. It is responsible for pressurizing automatic transmission fluid, a pressurization that supplies the force necessary to shift transmission gears.

A worn or dysfunctional torque converter can prevent transmission fluid from being properly pressurized, which in turn negatively impacts transmission gear function and operation. A systematic checkup by a professional is the best way to isolate the cause of the operating problems and recommend the most effective solution.

If properly tuned, this complex device can have a tremendous impact on your vehicle’s performance, economy and durability, and turn your automatic into a powerhouse!

Module Programming

The Transmission Control Module or TCM uses incoming sensor data to determine when the transmission needs to shift. TCM functionality has improved over the years, adding input from cruise control, throttle and traction control system. This reduces gear hunting and wheel spin. Auto Manufacturers are continually updating controller software to solve problems such as false diagnostic trouble codes, hesitation, rough idle, emissions problems, hard starting, poor fuel economy and other issues. If you’re not under warranty or using a dealer for tune-ups, your car could benefit from reflashing. Transmission Control Module (TCM) reflashing is essentially a software upgrade. TCMs are built with microchips that can be reprogrammed electronically without being removed from the vehicle. Reflashing is a process where you electronically transfer approved files from a vehicle manufacturer’s website using a diagnostic connector.

This process has many names. You might hear the terms TCM programming, TCM reprogramming, TCM flash, or TCM reflash. Dealers or car repair shops might call it a PCM/TCM or ECM reprogramming service. They all refer to an upgrade of your PCM’s microchip.

Coolers & Cooler Lines/Hoses

The transmission cooling line system is vital to any automatic transmission. It circulates the hot fluid away to the radiator via cooler lines and returns the cooled fluid back to the transmission. A loss of fluid leading to an overheated transmission can be devastating as the system loses its ability to cool.

Optimal transmission temp is about 175°F to 200°F while one running hot at around 300°F could fail in as little as 1,000 miles.
That is why it is important that any car owner hoping to keep their car’s transmission healthy will need dependable, leak-tight automatic transmission cooling system to carry that fluid to and from the transmission cooler. At Wisener’s Auto Clinic we offer thorough system inspections designed to pinpoint any leaks in your transmission cooling system.