C0055 on GMC: How to Diagnose & Fix
Rear Wheel Speed Sensor Circuit
1 GMC model · 1 documented issue · $300-$900 repair
C0055 on GMC by model: symptoms, diagnosis and fix
Front wheel hub bearing assemblies on Sierra 1500 trucks commonly wear out, especially on 4WD models and trucks used with larger tires or in rough conditions. Owners report humming or growling that changes with speed, looseness in the front wheel, and in some cases ABS warnings or low-speed ABS activation because the wheel speed sensor is integrated into the hub. This is a frequent repair item across both GMT800 and GMT900 generations.
Common Symptoms
- humming or growling from front end
- noise increases with vehicle speed
- wheel play or looseness
- ABS light on
- traction control warning
- low-speed ABS activation
How to Fix
Diagnosis involves checking for wheel play with the tire off the ground, listening for bearing noise during road tests, and comparing wheel speed sensor data if ABS symptoms are present. Repair is replacement of the affected hub assembly, and many owners replace both sides if mileage is high. Corrosion at the sensor mounting surfaces and wiring damage should also be addressed to prevent repeat ABS issues.
Sources for this issue (1)
C0055 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does C0055 mean on a GMC?
C0055 stands for "Rear Wheel Speed Sensor Circuit." This chassis code means the ABS/control module detected a problem with the rear wheel-speed sensor signal circuit. Wheel-speed sensors tell the module how fast each wheel is turning so it can manage anti-lock braking, traction, and stability control; on many GM trucks and SUVs this code points to a single rear/output speed sensor at the transmission or transfer case. A lost or erratic signal typically disables ABS and traction control (warning lights on), affecting braking safety, so it should be addressed promptly. On GMC it is documented across 1 model: Sierra 1500.
What are the most common causes of C0055?
The most common causes of C0055 are: Faulty rear/vehicle speed sensor, Damaged, corroded, or open sensor wiring and connector, Debris or damage on the reluctor/tone ring, Excessive air gap or sensor mounting issue, Poor ground or shorted circuit, Faulty ABS/EBCM module (less common). The specific cause varies by vehicle.
How much does it cost to fix C0055 on a GMC?
Published repair estimates on GMC range from $300 to $900 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for C0055 on a different make?
View C0055 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.