What Causes a Car Not to Move When in Gear?
1 Answers
Failure to shift gears in a car is a comprehensive functional issue involving the clutch, transmission, and drive axle. When diagnosing, first determine the faulty component, and you can start by checking the condition of both wheels. The diagnostic sequence typically proceeds from the drive wheel to the rear axle, then to the driveshaft, and finally to the clutch. If the driveshaft rotates but the car does not move forward, the issue lies with the rear axle. Lift the rear axle and rotate one rear wheel. If the opposite rear wheel turns in the reverse direction while the driveshaft does not follow, it indicates that all the rivets of the differential side gear are sheared. If the opposite rear wheel does not turn, check if the axle shaft is broken. When the car starts in a certain gear and the driveshaft does not rotate, the fault is in the transmission. Remove the transmission cover and check if the transmission shift fork is broken or if the guide block fixing screws are loose. If the above checks are normal, perform a shift test again. If the second shaft does not rotate in a certain gear, the half-round key of the gear is sheared; if the second shaft rotates in direct gear but does not rotate in other gears, the support bearings at both ends of the intermediate shaft may be separated, causing the intermediate shaft to drop. If the driveshaft does not rotate in any gear, the fault lies with the clutch. Check if the clutch is severely slipping, if the spline hub of the driven plate and all the steel plate rivets are sheared, or if the steel plate is broken.
