Car transmission problems can be notoriously difficult to diagnose, even for experienced mechanics. Nevertheless, being a little knowledgeable about the most frequently found difficulties can be helpful when you take your car in for repair. This way, you should know whether what your mechanic is telling you makes sense from the symptoms you have experienced behind the wheel.
Grinding and Shaking
When a car's transmission is faulty, this can often lead to nasty grinding noises being heard as well as the vehicle shaking, particularly when pulling away from a stationary position. This is usually down to a problem with the car's gearbox. If so, you ought to notice the problem is worst as you engage the clutch after changing gear. For automatics, it tends to be that the car wobbles a bit before the automatic gearbox feels like it is engaged properly.
In some cases, grinding can be heard because there is a fault either with the drive shaft or the universal joint to which it is joined. Bear in mind that this is not a transmission fault, strictly speaking, but a problem with the drivetrain. Repairs to this part of a vehicle should fall under your drivetrain car warranty, not the transmission system.
A car with leaky oil may have its transmission seize up entirely. Allowing a car's leak to go unattended is probably the most common cause of a transmission problem. If you cannot observe the source of leaking car fluids for yourself, then keep the oil reserve topped up until you can have it inspected professionally. Wilfully driving on without sufficient oil may invalidate your car engine warranty, so be sure to have it sorted out sooner rather than later to avoid unnecessary costs.
When checking the level of oil using your car's dipstick, remember to only do this after the engine has warmed up a little. Take it for a short spin and come to a stop on a level surface in order to gain a true reading of the oil level.
Uneven Clutch Sensation
Only found in manual cars, a feeling of unevenness when the clutch is depressed and re-engaged is a common transmission problem. A so-called 'dragging clutch' is often caused by the clutch disc failing to fully disengage from the flywheel when you press the clutch pedal. At its worst, this means that the clutch continues to spin with the engine making it hard to switch gears. A small adjustment to the disc's position may be all that is needed, but if it has also been grinding, then a replacement may have to be fitted.