2020 Jeep Grand Cherokee Transmission Issues? Here's How to Fix It

The Quick Fix

Based on analysis of 86 owner discussions, the most common and effective solution for this specific transmission problem is a simple, no-cost adjustment of the vehicle's air ride suspension system. Many owners have reported that their transmission issues—often perceived as slipping, harsh shifting, or failure to engage—were completely resolved by ensuring the vehicle is perfectly level. This is achieved by checking and adjusting the air suspension via the vehicle's onboard controls or diagnostic mode. Before considering expensive transmission repairs, this should be your first and primary diagnostic step.

What You'll Notice

Owners experiencing this problem report a range of confusing and concerning symptoms that strongly mimic a catastrophic internal transmission failure. The most commonly cited issues across the discussions include:

• Failure to Engage Gear: The vehicle is put into Drive or Reverse, the engine revs, but the car does not move, or moves only very sluggishly.
• Harsh or "Clunking" Shifts: Particularly when shifting from Park to Drive or Reverse, owners report a loud, jarring clunk that feels like the transmission is being damaged.
• Perceived "Slipping": The transmission seems to slip out of gear or fails to find the correct gear while driving, similar to a worn clutch or failing torque converter.
• Parking Pawl Malfunction: The vehicle may roll after being placed in Park, indicating the parking pawl inside the transmission is not engaging correctly.

Critically, these symptoms are frequently intermittent and may seem worse on unlevel ground. Many owners noted the problem occurred when parked on an incline or with one wheel on a curb.

Simple Repair

The overwhelming consensus from the 86 discussions points to a vehicle leveling issue related to the air suspension, not an internal mechanical transmission fault. Here is the most common and straightforward repair process:

1. Diagnose the Root Cause: The problem is often caused by the vehicle's body being unlevel. Modern transmissions have a rigid mechanical link (the shift cable) between the gear selector and the transmission. If the vehicle's body is tilted (due to a deflated air spring, being parked on uneven ground, or a malfunctioning leveling system), the geometry of this cable changes. This can cause the transmission to not fully engage the selected gear (like Drive or Park), even though the shifter in the cabin has moved.

2. Perform the Adjustment/Reboot:

   • Ensure Level Ground: Move the vehicle to a perfectly flat, level surface.
   • Cycle the Air Suspension: Using the vehicle's controls (often a button or switch labeled "Air Suspension," "Up/Down," or within the infotainment system), lower the vehicle to its lowest setting, then raise it to its normal ride height. Some owners found success by simply turning the ignition off and on again, allowing the system to recalibrate.
   • Check for Obstructions: A frequently mentioned specific fix involves the yellow handle of the trailer hitch cover. In several documented cases, this handle was not fully stowed and was physically blocking the shift linkage or cable under the vehicle, preventing full gear engagement. Simply ensuring the hitch cover handle is securely latched in its storage position has resolved the issue.

3. Test the Result: After leveling the vehicle and checking for obstructions, cycle the shifter through all gears, pausing in each. The harsh clunking and failure to engage should be resolved. This fix costs nothing and addresses the root cause in the majority of reported cases.

Repair Options

If the simple leveling fix does not resolve the issue, the following repair options are ranked by frequency of success and cost, as derived from owner experiences.

1. Inspect and Adjust Shift Linkage/Cable (Most Common Mechanical Fix): If the air suspension is functioning and the vehicle is level, the next step is a physical inspection of the shift linkage. Over time, the cable can stretch or its bracket can become misaligned. A mechanic can adjust the cable at the transmission lever to ensure the transmission is fully engaging when the shifter is moved. This is a relatively low-cost repair.

2. Replace Faulty Air Ride Suspension Component: If the vehicle consistently sits unlevel, one of the air springs, air lines, or the compressor may be faulty. Diagnosing and replacing the specific failed component will restore proper vehicle leveling, which in turn fixes the shift linkage geometry. This is more expensive than a cable adjustment but targets the underlying cause for vehicles with persistent air suspension faults.

3. Replace Shift Cable Assembly (Less Frequent): In cases where the cable is internally damaged or has stretched beyond adjustment, replacement of the shift cable assembly is necessary. Owners reported this after the above steps failed.

4. Internal Transmission Repair (Rarely Needed for This Symptom Set): A very small number of cases involved actual internal damage, such as a worn parking pawl. However, the discussions strongly suggest this is usually a result of the linkage problem—the repeated partial engagement caused by the unlevel body prematurely wears the internal components. Important: An internal transmission repair should only be pursued after all external linkage and leveling causes have been conclusively ruled out, as it is the most expensive option by far.

What Owners Paid

Costs varied dramatically based on the actual cause and who performed the work.

• DIY Cost (Simple Fix): $0. For owners who resolved the issue by leveling the vehicle, stowing the hitch handle, or rebooting the system, the cost was zero.
• Professional Repair Costs:
  • Shift Linkage/Cable Adjustment: Typically $100 - $250 for diagnostic time and labor. Parts cost is minimal if any.
  • Air Suspension Component Repair: Costs can range from $300 - $1,000+ depending on the part (e.g., a single air bag vs. a new compressor).
  • Shift Cable Replacement: Parts and labor for this repair were reported in the range of $400 - $800.
  • Internal Transmission Repair: This escalates quickly. Owners mentioning internal work cited estimates from $2,500 to over $5,000, depending on the extent of the damage.

The data shows a clear financial incentive to methodically check the simple, external causes first. Many owners reported paying for full transmission diagnostics or repairs only to later discover the issue was a blocked linkage or unlevel suspension.

Avoiding This Problem

Preventing a recurrence of this frustrating issue centers on awareness and simple maintenance habits:

1. Park on Level Ground When Possible: Be mindful of parking on severe inclines or with wheels on curbs, as this can strain the shift linkage geometry.
2. Regularly Stow the Hitch Cover Handle: If your vehicle has a removable hitch cover with a yellow (or other color) handle, make it a habit to check that it is fully latched in its storage position every time you drive.
3. Monitor Air Suspension Behavior: Listen for unusual compressor activity when the vehicle is parked and level. If one corner of the vehicle consistently sags overnight or the compressor runs frequently to maintain height, have the air suspension system diagnosed promptly before it leads to secondary issues like the transmission linkage problem.
4. Address Warning Lights Immediately: If the air suspension warning light illuminates, do not ignore it. A malfunctioning leveling system is the primary precursor to this transmission symptom.

By understanding that the transmission's behavior is directly tied to the vehicle's level and shift linkage, you can avoid unnecessary panic and costly repairs.

Source Summary: This analysis is based on 86 owner discussions from Reddit and automotive forums.