240,000 Miles In, My 2016 Toyota Tundra SR5's Random Braking Problems Arose Without Warning

A Toyota Tundra Nation Facebook group recently highlighted an issue many high-mileage Tundra owners might relate to: a mysterious, unpredictable problem with the ABS light, speedometer fluctuations, and unprompted light braking. Rick, a Tundra owner, shared his challenge with the group, asking for input on an issue affecting his 2016 Toyota Tundra SR5 CrewMax with 240,000 miles. With his ABS light turning on sporadically, the brakes lightly engaging on their own, and his speedometer giving inaccurate readings, Rick was eager for advice. Fortunately, fellow Tundra owners jumped in with helpful insights based on their own experiences and knowledge.

Good afternoon, everyone. I have a 2016 SR5 CrewMax 5.7 with 240,000 miles. Recently, without warning and at random speeds, the ABS light turns on, the brakes apply lightly, and the speedometer fluctuates slightly on the highway. Additionally, the speed reading is off by about 5 mph compared to GPS (it used to be much closer). I replaced the output speed sensor on the transmission, which helped a bit, but didn’t fully resolve the issue. I used a Duralast part. Any advice would be greatly appreciated. I’d rather avoid dealer service due to their high costs.

Rick's Issue: 2016 Tundra's ABS Light, Random Braking, and Speedometer Inaccuracy

With a high-mileage vehicle like Rick’s Tundra, intermittent and confusing electrical and sensor-related issues are not uncommon, especially in models with over 200,000 miles. Components like sensors, bearings, and electronic parts can wear down or miscommunicate with the vehicle's systems, causing the truck to react in unusual ways. When the ABS light illuminates and light braking occurs unprompted, this usually points to traction control or ABS system issues, both of which are closely connected to various speed sensors and the vehicle’s onboard computer.

Suggestions from Fellow Tundra Owners

Rick received valuable insights from another group member, Joe, who advised on possible causes of the issue. Joe pointed out that the symptoms Rick described could stem from several potential factors, emphasizing the importance of diagnostics and using OEM (original equipment manufacturer) parts.

1. Consider Running a Diagnostic Scanner

Joe’s first suggestion was to connect the Tundra to a diagnostic scanner: “I would put it on a scanner just to see if you can find anything out of sorts.” This is a crucial first step, as a diagnostic tool can read any error codes that may be stored in the vehicle's system, even if no check-engine light is illuminated. Although Rick’s problem didn’t trigger an immediate warning code, there’s a chance that the ABS or traction control systems recorded a fault that could help narrow down the issue.

2. Suspect a Faulty Wheel Speed Sensor or Brake Component

Joe then explained how the wheel speed sensors play a significant role in the ABS and traction control functions: “If it is applying the brakes at random times and kicking in the traction control, it thinks it’s losing traction. It could be a bad wheel speed sensor, a brake sticking, or a worn-out suspension component like a pitman arm.”

The Tundra’s ABS system relies heavily on accurate readings from the wheel speed sensors. If one of these sensors is malfunctioning, it could mistakenly detect a difference in wheel speed, signaling the ABS to engage, even if there’s no actual traction loss. Additionally, the wheel speed sensor is indirectly connected to the speedometer function, so a fault there could cause the speedometer to display inaccurate information.

Understanding the Role of Wheel Speed Sensors and OEM Parts

Rick responded to Joe, stating he had recently replaced the rear wheel speed sensors during a wheel bearing job, but hadn’t replaced the front ones yet. Considering his speedometer issues, Rick noted, “I didn’t read anywhere that the wheel speed sensor could affect the speedo; I thought it was handled through the transmission. Good to know.”

Joe elaborated on this, explaining that while wheel speed sensors don’t directly control the speedometer, they can indirectly affect it if they’re faulty: “The wheel speed sensors typically don’t affect the speedometer, but they can cause all kinds of problems, including speedo issues, and can even cause the speedo to quit working completely.”

Joe also shared his perspective on the importance of using OEM parts for sensor replacements: “I see that you mentioned you used a Duralast OSS (output speed sensor). I would only use OEM parts, especially for electronics. There have been countless horror stories on aftermarket sensors and other non-OEM parts. It is always best to use OEM.”

This advice is critical. OEM parts are designed specifically for the vehicle and have undergone rigorous testing by the manufacturer, so they generally offer better compatibility and reliability compared to aftermarket options. Non-OEM parts can sometimes work initially but may cause issues over time or underperform in critical areas.

Potential Causes of ABS and Traction Control Activation

Joe’s insights led Rick to believe that replacing his front wheel speed sensors with OEM parts might help, but the problem could still be multifaceted. Here’s a summary of potential culprits based on Joe’s advice and general troubleshooting for this issue:

1. Faulty Wheel Speed Sensor: The wheel speed sensors could be malfunctioning, especially if they’re worn, dirty, or incorrectly calibrated. These sensors play a key role in both ABS and traction control, and a faulty reading can confuse the vehicle’s electronic systems, causing unexpected braking and incorrect speedometer readings.
2. Brake Component Issue: Sometimes, brakes can engage lightly on their own if there’s a sticking caliper or worn brake component. If the brakes are engaging at random, it might be worth inspecting the brake components for wear or sticking.
3. Suspension or Steering Component Wear: Worn components, like a pitman arm, can impact the alignment and wheel stability, causing wheel sensors to report inconsistent speeds. Joe highlighted this as a possibility, especially on high-mileage vehicles.
4. Non-OEM Output Speed Sensor (OSS): Using a non-OEM output speed sensor, like the Duralast part Rick used, could be contributing to the issue. Non-OEM sensors might not communicate perfectly with the vehicle’s systems, leading to inconsistencies in speed readings or ABS activation.

Moving Forward: Troubleshooting and Repair Recommendations

Based on the feedback Rick received, here’s a step-by-step approach he could take to address his Tundra’s issues effectively:

1. Run a Diagnostic Scan: A diagnostic tool could reveal fault codes or inconsistencies in the ABS or traction control systems, which could lead Rick directly to the problem.
2. Replace Front Wheel Speed Sensors with OEM Parts: Since Rick has already replaced the rear wheel speed sensors, changing the front sensors with OEM parts could ensure all sensors are functioning correctly and eliminate any inconsistencies.
3. Consider Replacing the OSS with an OEM Part: Given that Joe emphasized the potential downsides of aftermarket electronic components, switching out the Duralast OSS for an OEM part might help resolve the speedometer issues.
4. Inspect Brake and Suspension Components: If the issue persists, it may be worth thoroughly inspecting the brake and suspension systems. A sticking brake caliper or worn suspension part could be triggering the ABS or traction control systems to engage unnecessarily.
5. Test on the Road: After any repairs, it’s essential to test-drive the vehicle under various conditions to verify that the problem is resolved.

Rick’s experience with his high-mileage Tundra underscores the complexities of modern vehicle diagnostics, especially when dealing with electronic systems. The advice he received from Joe and others in the Tundra community highlights the importance of using OEM parts for sensor replacements and taking a methodical approach to troubleshooting.

For Tundra owners facing similar issues, Rick’s story serves as a reminder that ABS and traction control issues can have multiple underlying causes, often requiring a combination of diagnostics, quality replacement parts, and patience. By taking a systematic approach and prioritizing OEM components, owners like Rick can potentially avoid lengthy, costly repairs and restore their trucks to smooth operation.

Also see: 7,000 Miles In, My Brand New 2024 Toyota Tundra Turns Into a Warranty Battleground (Seeking Advice!).

Armen Hareyan is the founder and the Editor in Chief of Torque News. He founded TorqueNews.com in 2010, which since then has been publishing expert news and analysis about the automotive industry. He can be reached at Torque News Twitter, Facebook, Linkedin, and Youtube. He has more than a decade of expertise in the automotive industry with a special interest in Tesla and electric vehicles.