* Reverse gear itself: The reverse gear within the transmission could be stripped, broken, or otherwise damaged. This is the most straightforward but potentially serious problem.
* Reverse idler gear: Many manual transmissions use an idler gear for reverse. This gear could be worn, broken, or its teeth damaged.
* Shift linkage: The linkage connecting the shift lever to the transmission could be misadjusted, bent, broken, or disconnected specifically for the reverse gear. This is a relatively easier and cheaper fix if this is the problem. Inspect the linkage carefully for any visible damage.
* Shift fork: The shift fork responsible for selecting reverse might be bent, broken, or worn, preventing it from properly engaging the reverse gear. This requires opening the transmission to inspect.
* Clutch issues (less likely): While less probable given that drive works, a clutch problem *could* indirectly affect reverse if it only partially engages under the specific force and angle needed for reverse.
* Low transmission fluid: While unlikely to completely disable reverse while leaving other gears fine, very low transmission fluid can cause various shifting problems. Check your transmission fluid level immediately.
What you should NOT do: Continue driving with the problem. Forcing the shifter or putting stress on the transmission could worsen the damage and lead to more expensive repairs.
What you SHOULD do:
1. Check transmission fluid: This is the easiest and quickest check. Low or dirty fluid can cause shifting problems.
2. Inspect the shift linkage: Carefully examine the linkage for any obvious damage, bending, or disconnections.
3. Consult a mechanic: This is the most important step. Diagnosing and repairing transmission issues often require specialized knowledge and tools. A mechanic can properly diagnose the problem and provide an accurate repair estimate.
Trying to fix a manual transmission problem yourself without experience is strongly discouraged, as it's easy to cause further damage. A professional inspection will provide the most accurate diagnosis and prevent unnecessary repairs or further damage.
