It is very important for a transmission to be serviced on a regular basis. We recommend either every 12 months or 20,000 kms. This will ensure that the transmission is thoroughly checked and minor repairs fixed before they cause major breakdowns. Most car owners do not know that a transmission exists in their car until a problem occurs. Transmissions need to be serviced before a problem occurs – never wait for a problem to occur.
Oil leaks – If a transmission has an oil leak, it can cause slippage on the clutch application which will cause the transmission to become hot and burn out. The transmission oil then gets too hot, it will cause electrical components to fail due to over heating.
Radiator -The radiator has a separate section for the transmission oil to be cooled. It is very important that the flow is at full capacity. If there is a slow flow due to the cooler failing, it will not allow the various transmission parts, such as clutches, bands and bushes, to be lubricated. This will cause the transmission to burn out. Water can also leak into the cooling side of the transmission which is caused by not changing or flushing out the radiator on a regular basis. Oil mixed with water will cause the oil to discolour. A transmission which is contaminated with water will not work well.
Filter blockage – If a transmission has not been serviced for a long time, the filter can clog up with material from normal wear and tear which will cause the transmission to starve of oil. This will result in the loss of “drive” and “reverse”.
Bands – Bands lock a spinning component called a drum which is similar to the motion of applying brakes to stop a car. Most transmissions have 1 or 3 bands which can wear or break over time. Harsh driving can cause a band to break resulting in losing one or more gears. A worn band will cause a long drawn out shift which is known as a flair shift.
Electrical Components – Solenoids are used for “on” and “off” motions. They allow oil to pass through and to cease oil flow. Pressure solenoids control pressure. Some pressure solenoids become contaminated and start to stick which causes high pressure and very firm shifts.
Pulse Generators and Transducers – They count the turns of a spinning component and send a message to the ECU (electronic control unit) computer. Pulse generators are powered by a magnetic field which can be contaminated by foreign metal particles. When this occurs, the pulse generator sends the wrong messages to the ECU. This can cause a fault code which will cause the transmission to only operate in 3rd gear.
Other Electrical Components – There are many more electrical components such as: Inhibitor, throttle position sensor, ECU computer, and wiring heat sensors. The engine light comes on when it detects an electrical fault in the transmission or engine. This can cause a fault code which will cause the transmission to only operate in 3rd gear. The T-bar or column shifters are very sensitive and if they are not aligned correctly, they can send the wrong message to the ECU which will in turn cause problems in the transmission.
These are only a few examples of what can go wrong with your transmission.
Being a family operated business, we take personal care of all our customer’s cars. We have over 30 years of experience and have worked on all types of cars – both classical and modern. A transmission is a complex unit and requires specialist transmission mechanics to work on them so that they are correctly diagnosed. At Accurate Automatics, our specialisation is transmissions and therefore we can provide you with the right advice & price.