How to Repair a Car Gearboxby Peter Grant
As your car gains in mileage, the transmission and its components can wear down and eventually break. Depending on the cause of your transmission failure, there are several ways to repair it and bring it back to working order. Some are more costly than others, however one option is more than likely to solve your woes.
Check the transmission fluid in your engine bay. Refer to your car's owners manual to determine which fluid reservoir in your engine bay is for the transmission fluid. Add more if necessary. If the fluid is low, you can experience trouble shifting gears, and you may hear gears grinding when you do. This is one of the more economical repairs that you can perform, but may not solve all issues.
Replace one, or more, problematic gear synchros that are responsible for housing the individual gears in your transmission. These tend to wear down faster on manual transmission cars. Your synchro may be wearing down if you're encountering resistance pushing the car into gear or you're hearing some loud grinding noises during upshifts and downshifts. If left unattended, this can severely damage the rest of your gearbox.
Check that your differential and drivetrain components are working correctly as they interact directly with your car's gearbox. Low differential fluid, worn down differentials, and broken driveshafts can contribute to poor gearbox performance and shifting smoothness. Consider replacing these components if they are diagnosed as being the culprits to help repair your gearbox.