4 Important Avenues to Explore When Diagnosing Transmission Problems

23 June 2016
 Categories: Automotive, Blog


The transmission is responsible for enabling you to change gears in your car. This is made possible by a complex system which you may not understand as a layperson. If you're having problems with your transmission, however, understanding some of the basics will help you have a more candid conversation with your mechanic. Transmission breakdowns may manifest in two ways: the car doesn't go or doesn't go smoothly. These are usually caused by the same kinds of faults. Below are some of the avenues to explore in the diagnostic and repair process.

1. Clogged Filters

The filter keeps your transmission fluid clean to enable the transmission to work properly when you shift gears. The state of the filter is vital to the performance of the transmission. If it has not been replaced in some time (or ever), this is the perfect place to begin the diagnostic process, before thinking about replacing or rebuilding anything.

2. Low transmission fluid levels

If you have insufficient transmission fluid, the gear system, which is hydraulically powered, will not respond as smoothly, and this will ultimately lead to further damage that results in more costly repairs. You should inspect your fluid levels every few months. If you have to replenish too often (more than once or twice a year), there could be a leak somewhere.

3. Transmission system leaks

Your transmission is a closed loop, hence there are a finite number of places where leaks can come from. In most vehicles, the transmission fluid is red (good to know in case of a leak), but it typically grows darker as the oil ages. Take note of the colour if you change it to something different. The following are the most common places where leaks can spring up:

  • Drain-hole below the transmission
  • Filler tube base
  • Between the engine and transmission
  • At the selecting shaft – connects your gear shift rod to the internal transmission system
  • Radiator – if you notice transmission fluid floating over your radiator fluid, since the two do not mix
  • Speed sensor – an electronic component bolted to your transmission or a cable screwed into the housing

Once you know where the leak comes from, you need to determine how big it is to know whether you can fix it yourself or you need specialized service. A few drops or fluid on the ground indicates a small leak, while small puddles indicate much larger leaks. In the latter event, the best thing to do is to top up the fluid to the required levels, which allows you to safely travel the distance to the repair shop.

4. Time for a rebuild

After using the transmission system for a long time, you may have to have it rebuilt. This is also true if you've explored the above avenues and the system is still not working properly. However, start with the simpler solutions before allowing the mechanic to take it apart, as the latter is very expensive. If you need a rebuild, confirm with the shop whether they offer a warranty on the rebuild – this way you can be sure that your investment is secure. However, properly maintaining your car transmission will keep it working properly and reduce instances when costly repair procedures must be carried out.