FAULTBASE
Error CodesASKCars
© 2026 FAULTBASE
All rights reserved.
v2.0.0 • Production
ContactPrivacyImpressum
What causes transmission slipping in the 2020 Toyota Highlander? - Toyota Highlander
Home/Cars/Toyota/Highlander/Fourth Generation (2020-present)/What causes transmission slipping in the 2020 Toyota Highlander?

What causes transmission slipping in the 2020 Toyota Highlander?

Toyota Highlander Fourth Generation (2020-present)

Error Codes
3-5 hours
Time
medium
Difficulty
medium
Severity
Navigation
ProblemSymptomsDiagnosisSolution
ProblemSymptomsDiagnosisSolution
4 min read
674 words

Problem Statement

Learn about the causes of transmission slipping in the 2020 Toyota Highlander, including symptoms, diagnostic steps, and repair instructions.

Affected Component
Transmission
Estimated Time
3-5 hours

Symptoms

  • •Unresponsive Acceleration
  • •Delayed Shifts
  • •High RPMs
  • •Sudden Loss of Power
  • •Warning Lights

Diagnostic Steps

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6

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
  • •Transmission fluid (Toyota WS ATF)
  • •Hand tools (sockets, wrenches, screwdrivers)
  • •Torque wrench
  • •Fluid catch pan
  • •Transmission filter kit (if filter replacement is needed)

Additional Information

Affected Component
Transmission
Estimated Time
3-5 hours
Difficulty
medium
Severity
medium
Tools Required
7 items

Related Faults

Loading...

Share this solution

Comments

Sign in to share your thoughts

Sign In

No comments yet

Be the first to share your thoughts

Back to Generation
Causes of Transmission Slipping in the 2020 Toyota Highlander

Transmission slipping in the 2020 Toyota Highlander can be attributed to several factors, primarily related to fluid levels, electrical issues, or mechanical failures. Below, we outline the symptoms, diagnostic steps, tools required, and repair instructions.

Tools Required
  • OBD-II Scanner
  • Transmission fluid dipstick
  • Transmission fluid (Toyota WS ATF)
  • Hand tools (sockets, wrenches, screwdrivers)
  • Torque wrench
  • Fluid catch pan
  • Transmission filter kit (if filter replacement is needed)
Repair Instructions

1. Fluid Change

If the fluid is low or in poor condition:

  1. Drain the Transmission Fluid:

    • Place a fluid catch pan underneath the transmission pan.
    • Remove the transmission pan bolts and carefully lower the pan to drain the fluid.
    • Replace the transmission pan gasket if damaged.

  2. Replace the Transmission Filter:

    • If equipped, remove the old filter and install the new filter according to the service manual specifications.

  3. Refill Transmission Fluid:

    • Reinstall the pan and tighten the bolts to the manufacturer’s torque specifications.
    • Fill the transmission with new fluid through the dipstick tube using a funnel, ensuring to use Toyota WS ATF.

  4. Check Fluid Level:

    • Start the engine and allow it to warm up.
    • Check the fluid level again and add more fluid as necessary.

2. Electrical Issues

If your diagnostic scan reveals electrical faults:

  1. Inspect Wiring and Connectors:

    • Disconnect the TCM and inspect the wiring for corrosion or damage.
    • Repair or replace any damaged wiring or connectors.

  2. Test TCM:

    • If the wiring is intact, test the TCM for proper operation using a multimeter or TCM diagnostic tool.
    • Replace the TCM if faulty.

3. Mechanical Issues

If slipping persists after checking fluid and electrical systems:

  1. Assess Clutch Packs/ Bands:

    • Remove the transmission from the vehicle.
    • Disassemble the transmission to inspect clutch packs and bands for wear or damage.
    • Replace worn components as necessary.

  2. Reassemble and Reinstall:

    • Reassemble the transmission with new gaskets and seals.
    • Reinstall the transmission in the vehicle following appropriate torque specifications for all bolts.

  3. Final Testing:

    • Once repairs are made, perform a test drive to verify the transmission operates smoothly without slipping.
Conclusion

Transmission slipping in the 2020 Toyota Highlander can arise from fluid issues, electrical faults, or mechanical failures. Following the outlined diagnostic and repair steps can help you identify and resolve the issue effectively, ensuring the vehicle operates properly. Always refer to the vehicle’s service manual for specific torque specifications and procedures tailored to the Highlander.