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What common issues are related to the Toyota Highlander 2020's transmission? - Toyota Highlander
Home/Cars/Toyota/Highlander/Fourth Generation (2020-present)/What common issues are related to the Toyota Highlander 2020's transmission?

What common issues are related to the Toyota Highlander 2020's transmission?

Toyota Highlander Fourth Generation (2020-present)

Error Codes
medium
Difficulty
medium
Severity
Navigation
ProblemSymptomsDiagnosisSolution
ProblemSymptomsDiagnosisSolution
4 min read
629 words

Problem Statement

Explore common transmission issues in the 2020 Toyota Highlander, including symptoms, diagnostic steps, tools required, and repair instructions.

Affected Component
transmission

Symptoms

  • •Slipping Transmission
  • •Delayed Engagement
  • •Unusual Noises
  • •Warning Lights
  • •Fluid Leaks
  • •Overheating

Diagnostic Steps

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

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
  • •Torque Wrench
  • •Screwdrivers (flathead and Phillips)
  • •Socket Set
  • •Transmission Fluid Pump
  • •Drain Pan
  • •Funnel
  • •Transmission Fluid (Toyota Type T-IV or equivalent)
  • •Torque Specifications Guide
  • •Safety Gloves and Goggles

Additional Information

Affected Component
transmission
Difficulty
medium
Severity
medium
Tools Required
10 items

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Back to Generation
Common Transmission Issues in the 2020 Toyota Highlander

The 2020 Toyota Highlander, part of the fourth generation (XU70), is generally reliable, but like any vehicle, it may experience some transmission-related issues. Below are common symptoms, diagnostic steps, tools required, and repair instructions for addressing these potential transmission problems.

Common Symptoms

  1. Slipping Transmission: The vehicle may unexpectedly change gears or struggle to maintain speed.
  2. Delayed Engagement: There is a noticeable lag between shifting into gear and the vehicle moving.
  3. Unusual Noises: Grinding, whining, or clunking sounds when the transmission is engaged.
  4. Warning Lights: The Check Engine light or transmission-specific warning lights may illuminate.
  5. Fluid Leaks: Puddles of reddish-brown transmission fluid under the vehicle.
  6. Overheating: The transmission may overheat, especially under heavy load or during towing.
Tools Required
  • OBD-II Scanner
  • Torque Wrench
  • Screwdrivers (flathead and Phillips)
  • Socket Set
  • Transmission Fluid Pump
  • Drain Pan
  • Funnel
  • Transmission Fluid (Toyota Type T-IV or equivalent)
  • Torque Specifications Guide
  • Safety Gloves and Goggles
Repair Instructions

1. Addressing Fluid Leaks

  • Identify Leak Source:

    • Clean the area around the transmission and look for fresh fluid.

  • Repair:

    • Tighten loose bolts or replace any damaged seals or gaskets.
    • If a transmission line is leaking, replace the line.

2. Changing Transmission Fluid

  • Prepare:

    • Park the vehicle on a level surface and set the parking brake.

  • Drain Old Fluid:

    • Place a drain pan under the transmission.
    • Remove the drain plug (if equipped) and allow fluid to drain completely.

  • Replace Filter (if applicable):

    • Remove the transmission pan (if applicable) by unscrewing the bolts.
    • Replace the filter and clean the pan before reinstalling it.

  • Refill Fluid:

    • Reinstall the drain plug and torque to specifications.
    • Use a funnel to refill the transmission with new fluid via the dipstick tube or designated fill port.

  • Check Fluid Level:

    • Start the vehicle and let it idle in park.
    • Check the fluid level again and add more fluid if necessary.

3. Addressing Electrical Issues

  • Check Connections:

    • Disconnect the TCM and inspect the connector for corrosion or damage.
    • Clean or replace as necessary.

  • Reprogramming:

    • If there are issues after clearing codes, the TCM may need reprogramming using a specialized tool.

4. Resetting the Transmission Control Module

  • Battery Disconnect:

    • Disconnect the negative terminal of the battery and wait for about 15 minutes.

  • Reconnect:

    • Reconnect the battery terminal and start the vehicle to see if the issues persist.
Conclusion

While the 2020 Toyota Highlander is a robust vehicle, transmission issues can arise. Regular maintenance and prompt attention to symptoms can help prevent significant problems. If issues persist after following these steps, it may be advisable to consult a professional technician or visit a Toyota dealership for further diagnosis and repair.