Dear customer, normally a consecutive gearbox problem or damage may indicate that a component may be incorrectly fitted, as although the original may fail due to a random fault or problem, a second gearbox should have a normal life span, when repeated failure occurs, it should be checked: The clearance between gears is correct, this causes the gearbox to make excessive noise. In cars with many kilometres behind them, it is logical that the gears wear out and make noises. This annoying noise is caused by poor seating of the gears between them as they have been losing material over the years. Solution? Dismantle the gearbox and open it. This work is expensive (about 1,000 euros) and, as a temporary measure, it may be a good solution to use a Teflon-based additive. Wear between the bearings is another of the 7 major faults in manual gearboxes. Wear of the bearings in the gearbox on which the shafts are supported can produce more noise than normal. As with gear backlash, the only solution is to uncouple the engine from the gearbox and open it up. This is a labour-intensive job that costs a lot of money. As a first step, we recommend the use of an additive to eliminate these noises. If the manual gearbox synchronisers are worn, it is possible that a gear may magically disengage. This is a common occurrence in cars that have been driven for many kilometres. Repairing this manual gearbox fault is very costly as you will have to dismantle the gearbox and open the gearbox. Again, you are faced with many hours of work and a high cost. The use of unsuitable oils or even partial and not complete replacement of gearbox components can cause these problems, in automatic gearboxes, there could be a problem in the wiring or solenoid body, which causes the problem to reappear after a short time, it is important at all times to be aware of the possible events that can cause damage of this kind.
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