1. Transmission Fluid:
* Low Fluid: Check the transmission fluid level. Low fluid is a common cause of shifting problems. The fluid should be bright red; dark brown or burnt-smelling fluid indicates problems. *Important:* Check the fluid level with the engine running and warmed up, as per your owner's manual.
* Dirty/Contaminated Fluid: Even if the level is okay, dirty fluid can cause problems. A fluid change might resolve the issue.
2. Transmission Linkage/Cables:
* Adjusted Incorrectly: The linkage that connects the shifter to the transmission can become misadjusted or worn. Inspect for any visible damage or looseness.
* Broken or Damaged Cables: Internal cables or linkages can break or become disconnected, preventing shifting. This requires a more in-depth inspection.
3. Solenoids (Automatic Transmission):
* Faulty Solenoids: If it's an automatic transmission, internal solenoids control shifting. A faulty solenoid can prevent gear changes. This usually requires professional diagnosis and replacement.
4. Transmission Control Module (TCM) (Automatic Transmission):
* TCM Issues: The TCM is the computer that controls the transmission. A malfunctioning TCM can cause various shifting problems. This needs professional diagnosis and potential replacement or reprogramming.
5. Shift Interlock:
* Stuck or Faulty: The shift interlock prevents the car from shifting out of park without the brake pedal depressed. A malfunctioning interlock could be preventing shifting.
6. Other Mechanical Issues (Automatic Transmission):
* Low/No Pressure: Internal problems within the transmission itself, such as worn clutches or bands, can lead to poor or no shifting. This is often a major repair.
* Valve Body Problems: The valve body manages fluid flow within the transmission. Problems here require professional attention.
7. Clutch (Manual Transmission):
* Worn Clutch: If you have a manual transmission, a worn clutch will prevent gear engagement. The clutch pedal may feel soft or spongy.
* Clutch Cable/Hydraulics: Issues with the clutch cable (if cable-operated) or hydraulic system (if hydraulic) can also prevent shifting.
Troubleshooting Steps:
1. Check Transmission Fluid: This is the easiest and most important first step.
2. Inspect Linkage/Cables: Look for any obvious damage or misalignment.
3. Try Starting and Shifting: See if you can force the shifter into different positions, noting any resistance or unusual sounds. Do this with the engine *off*.
4. Check Brake Pedal and Shift Interlock: Ensure the brake pedal is depressed fully when trying to shift out of park.
When to Seek Professional Help:
If you're not comfortable working on your transmission, or if the above steps don't resolve the problem, it's crucial to take your Explorer to a qualified mechanic or transmission specialist. Transmission repairs can be expensive, so a proper diagnosis is essential before undertaking any repairs. Ignoring the problem could lead to significant and costly damage.
