Diagnosis And Testing - Clash-Into-Reverse

Manual transmissions are equipped with a reverse synchronizer that reduces gear train spin down time after the clutch pedal is depressed. It prevents gear clash while shifting into reverse, when the vehicle is not moving.

1. Depress clutch pedal to floor and hold. After three seconds, shift to reverse. If clash is present, clutch has excessive spin time, and the reverse brake may not be functioning.
2. Remove the transmission.
3. Check the input shaft spline, clutch disc splines, and release bearing for dry rust. If present, clean rust off and apply a light coat of bearing grease to the input shaft splines. Apply grease on the input shaft splines only where the clutch disc slides. Verify that the clutch disc slides freely along the input shaft spline.
4. Check to see if the clutch disc hub splines are damaged, and replace with new clutch assembly if required.
5. Check the input shaft for damaged splines. Replace as necessary.
6. Check for broken clutch cover diaphragm spring fingers.
7. Install the clutch assembly and transmission.