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What are the common signs of a failing transmission in the 2020 Highlander? - Toyota Highlander
Home/Cars/Toyota/Highlander/Fourth Generation (2020-present)/What are the common signs of a failing transmission in the 2020 Highlander?

What are the common signs of a failing transmission in the 2020 Highlander?

Toyota Highlander Fourth Generation (2020-present)

Error Codes
medium
Difficulty
high
Severity
Navigation
ProblemSymptomsDiagnosisSolution
ProblemSymptomsDiagnosisSolution
3 min read
599 words

⚠️ Safety Warning

This issue requires immediate attention. If you are not experienced with automotive repairs, consult a professional mechanic. Working on critical systems can be dangerous.

Problem Statement

Learn about the common signs of a failing transmission in the 2020 Toyota Highlander, including symptoms, diagnostic steps, and tools required for inspection.

Affected Component
transmission

Symptoms

  • •Delayed or Sluggish Shifting
  • •Unusual Noises
  • •Fluid Leaks
  • •Warning Lights
  • •Burning Smell
  • •Inability to Shift Gears

Diagnostic Steps

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6
  7. 7
  8. 8
  9. 9
  10. 10

Solution

💡 Expert Tip

For complex repairs like this, consider taking photos at each step. This helps if you need to reverse a step or consult with a mechanic. Also, keep all removed parts organized - you may need to reference them during reassembly.

Verification

After completing the repair, verify that the issue has been resolved:

  • ✓Test the affected component to ensure it functions correctly
  • ✓Check for any error codes or warning lights
  • ✓Monitor the vehicle for a few days to ensure the issue does not recur

Prevention Tips

To prevent this issue from occurring again:

  • •Follow the manufacturer's recommended maintenance schedule
  • •Address warning signs early before they develop into major issues
  • •Use quality parts and fluids recommended for your vehicle
  • •Keep detailed records of all repairs and maintenance

Tools & Equipment Required

  • •OBD-II scanner
  • •Transmission fluid dipstick
  • •Ramps or jack stands
  • •Drain pan
  • •Towels or rags
  • •Safety gloves and goggles

Additional Information

Affected Component
transmission
Difficulty
medium
Severity
high
Tools Required
6 items

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Common Signs of a Failing Transmission in the 2020 Toyota Highlander

The transmission in a vehicle is crucial for transferring power from the engine to the wheels. In the 2020 Toyota Highlander, there are several symptoms that may indicate a failing transmission. Here are the common signs to look out for:

1. Delayed or Sluggish Shifting

  • Symptoms: Noticeable delay when shifting from park to drive or reverse, or between gears while driving.
  • Diagnostic Steps:
    • Test drive the vehicle to observe the shift response.
    • Monitor RPMs; unusually high RPMs before shifting may indicate issues.

2. Unusual Noises

  • Symptoms: Grinding, whining, or clunking noises when the vehicle is in gear.
  • Diagnostic Steps:
    • Listen carefully while driving, especially during shifts.
    • Check for any loose components under the vehicle.

3. Fluid Leaks

  • Symptoms: Puddles of reddish-brown fluid under the vehicle.
  • Diagnostic Steps:
    • Inspect the ground where the vehicle is parked.
    • Check the transmission fluid level and condition.

4. Warning Lights

  • Symptoms: Transmission or check engine light illuminated on the dashboard.
  • Diagnostic Steps:
    • Use an OBD-II scanner to check for transmission-related trouble codes.
    • Note the specific codes for further analysis.

5. Burning Smell

  • Symptoms: A burnt odor coming from the engine bay or cabin.
  • Diagnostic Steps:
    • Check the transmission fluid for a burnt smell or dark color.
    • Inspect the engine bay for any signs of overheating.

6. Inability to Shift Gears

  • Symptoms: The vehicle will not engage in drive or reverse.
  • Diagnostic Steps:
    • Attempt to shift gears and assess if there's resistance.
    • Inspect the gear shift mechanism for faults.
Tools Required
  • OBD-II scanner
  • Transmission fluid dipstick
  • Ramps or jack stands (for under-vehicle inspection)
  • Drain pan (for fluid checks)
  • Towels or rags (for cleaning spills)
  • Safety gloves and goggles
Repair Instructions

Step 1: Check Transmission Fluid Level and Condition

  1. Locate the Transmission Dipstick:
    • Open the hood and find the transmission fluid dipstick (if applicable; some models may not have one).
  2. Remove and Inspect:
    • Pull out the dipstick, wipe it clean, and reinsert it.
    • Remove it again to check the fluid level.
    • Check the color and smell of the fluid. It should be bright red and not have a burnt odor.
  3. Add Fluid (if low):
    • If the fluid is low, add the recommended transmission fluid as per the owner’s manual.

Step 2: Scan for Diagnostic Trouble Codes (DTCs)

  1. Connect the OBD-II Scanner:
    • Plug the scanner into the OBD-II port (usually located under the dashboard).
  2. Read Codes:
    • Follow the scanner instructions to read and document any trouble codes related to the transmission.
  3. Research Codes:
    • Use the manufacturer’s service information to understand the implications of the codes.

Step 3: Inspect for Leaks

  1. Visual Inspection:
    • Look under the vehicle for signs of fluid leaks.
  2. Check Seals and Gaskets:
    • Inspect the transmission pan, cooler lines, and seals for damage or wear.

Step 4: Test Drive and Observe Performance

  1. Perform a Test Drive:
    • Drive the vehicle under various conditions (stop-and-go, highway speeds) to replicate symptoms.
  2. Monitor Shifting:
    • Pay attention to any irregularities in shifting or performance.
Conclusion

If you observe any of the symptoms mentioned above, it is advisable to consult a professional automotive technician for further diagnosis and potential repairs. Transmission issues can escalate quickly if not addressed, leading to costly repairs or replacements.