1. Linkage and Cables:
* Shift Linkage Adjustment: The linkage connecting the shifter to the transmission could be out of adjustment. This is a common cause and often relatively easy to check and adjust. Look for loose or worn components in the linkage.
* Broken or Damaged Cables: If your Caprice has shift cables (rather than a completely mechanical linkage), they might be frayed, broken, or disconnected. Inspect them carefully.
2. Transmission Issues:
* Low Transmission Fluid: Check your transmission fluid level. Low fluid can cause a variety of shifting problems, including difficulty engaging gears. If it's low, find out *why* it's low – a leak is a serious problem.
* Fluid Condition: Is the fluid dirty, burnt, or smelling unusual? Bad fluid needs to be changed.
* Internal Transmission Problems: This is the worst-case scenario. Internal problems could include worn clutches, bands, or other internal components. This often requires a professional transmission repair or rebuild.
* Torque Converter Issues: A faulty torque converter can prevent the transmission from engaging properly.
3. Other Potential Causes:
* Clutch (if manual): If your Caprice is a manual transmission, the clutch itself could be worn, slipping, or improperly adjusted.
* Starter Motor: While unlikely to completely prevent gear selection, a faulty starter can sometimes interfere with the transmission's operation.
* Park/Neutral Safety Switch: This switch prevents the car from starting unless it's in Park or Neutral. A faulty switch could prevent gear selection.
What to Do:
1. Check the Transmission Fluid: This is the easiest and most important first step. Check the level and condition of the fluid while the engine is running (if possible and safe).
2. Visually Inspect the Linkage/Cables: Look for any obvious signs of damage, looseness, or disconnection.
3. Try the Shifter: Try shifting through all the gears (with the engine off and the parking brake engaged). If the shifter feels stiff or unusual, this points to linkage issues.
4. Consult a Repair Manual: A repair manual specific to your 1987 Chevrolet Caprice will provide detailed diagrams and instructions for checking and adjusting linkages, and troubleshooting transmission problems.
5. Seek Professional Help: If you're uncomfortable working on your transmission, or if the problem persists after checking the simple things, take your Caprice to a qualified mechanic. Improper transmission repair can be expensive.
Don't attempt any major repairs yourself unless you have experience working on transmissions. Incorrectly diagnosing and repairing transmission problems can lead to further damage and significant expense.
