GMC Sierra 3500 HD Engine Camshaft Position Sensor Guide (2017-2024)
Keep your Sierra's engine running smoothly by understanding camshaft position sensor failure and choosing the right replacement.
- A failing camshaft sensor can cause a Check Engine Light, stalling, rough idle, and no-start conditions.
- For a reliable repair, choose an OEM (ACDelco Genuine) or a reputable OEM-supplier brand like Delphi.
- Avoid budget-tier sensors from brands with poor reputations for electronics, as they have a high risk of early failure.
- This is a DIY-friendly repair that can be done in under an hour with basic tools.
What is a Camshaft Position Sensor and Why Does It Fail?
Think of the camshaft position sensor as the eyes of your engine's computer. It constantly tells the computer where the camshaft is in its rotation. This allows the computer to fire the fuel injectors and spark plugs at the perfect moment. When this sensor fails, the computer is essentially flying blind, leading to a host of engine problems.
On the 2017-2024 Sierra 3500 HD, especially those with the L5P Duramax engine, these sensors live in a harsh environment. Failures are often caused by:
- Heat Cycles: Constant exposure to high engine temperatures can break down the sensor's internal electronics over time.
- Oil and Soot Contamination: Oil leaks or soot from the emissions system can coat the sensor, interfering with its signal. This is a known issue in modern diesel engines.
- Internal Wear: After millions of engine rotations, the internal magnets can weaken, causing a poor signal.
Choosing the Right Aftermarket Sensor for Your Sierra HD
When it comes to engine sensors, not all brands are created equal. For a critical part like this, quality matters more than a few dollars saved. Aftermarket sensors for your Sierra can be grouped into tiers based on quality and reliability.
Tier 1: OEM & OEM-Equivalent Brands
These are the safest bets for a first-time, trouble-free repair. They are either the original part manufacturer for GM or have a long-standing reputation for matching OEM quality.
- ACDelco (GM Genuine): This is the original part that came on your truck from the factory. It offers the best guarantee of fit and function. Be aware that ACDelco has different lines; 'GM Genuine' is the top tier, while 'Gold' or 'Professional' are their aftermarket lines which may be made by other companies.
- Delphi: Delphi is a well-known original equipment manufacturer for many car brands, including GM. They are widely trusted by professional mechanics for sensors and electronics, and are often considered a true OEM-equivalent option.
Tier 2: Reputable Aftermarket Brands
These brands are known for producing quality parts that are a step above typical budget options. They are a good balance between cost and reliability.
- NGK / NTK: While famous for spark plugs, their sensor division (NTK) is highly regarded for making quality electronic components.
- Standard Motor Products (SMP): A long-standing brand in the aftermarket with a reputation for producing reliable sensors.
- Walker Products: Another established brand that focuses on fuel and engine management parts, often providing a dependable alternative to OEM.
A Word of Caution on Budget Brands
Brands like Dorman have a very mixed reputation for electronic parts. While they offer a wide variety of components, forum discussions among truck owners and mechanics frequently mention high failure rates for their sensors, sometimes being faulty right out of the box. While the low price is tempting, you may find yourself doing the job twice. For critical sensors, it's often best to invest in a higher-quality brand.
Cost to Replace the Camshaft Position Sensor
The replacement cost depends on whether you do it yourself or have a shop do the work. The part itself is relatively inexpensive.
| Item | Estimated Cost |
|---|---|
| New Aftermarket Part | $24.11 - $56.57 |
| New OEM Part (ACDelco GM Genuine) | $60 - $110 |
| Shop Labor | $80 - $150 |
| Total Professional Replacement | $105 - $260 |
DIY Replacement Tip
Replacing the camshaft position sensor on the Sierra 3500 HD is generally a straightforward job for a DIYer. The sensor is usually located on the front of the engine and held in by a single bolt. Always disconnect the battery before starting. After replacing the sensor, it's a good idea to clear the engine codes with a scanner.
Frequently Asked Questions
Are there any recalls for the camshaft position sensor on the 2017-2024 Sierra 3500 HD?
No, as of early 2026, there are no specific NHTSA recalls for the engine camshaft position sensor on this vehicle range. There is a Technical Service Bulletin (TSB #22-NA-080) related to a 'camshaft actuator magnet' causing an engine shudder, but it is not a recall for the sensor itself.
Can a bad camshaft sensor cause my truck not to start?
Yes. A completely failed sensor may not send any signal to the ECM. Without this data, the computer doesn't know when to fire the injectors or spark plugs, which can result in a crank-no-start condition.
Is it okay to use a cheap sensor?
It is generally not recommended. Critical engine sensors from budget brands are known to have higher failure rates. You might save money initially, but you risk the part failing quickly, leaving you stranded and needing to do the repair again. Sticking with OEM or reputable aftermarket brands like Delphi, NGK, or Standard is a safer investment.
Do I need to replace the crankshaft sensor at the same time?
It is not required, but it's sometimes recommended as preventative maintenance, especially on higher-mileage trucks. The camshaft and crankshaft sensors work together, and they are exposed to the same harsh conditions. If one has failed due to age and heat, the other may not be far behind.
Technical Specifications
OEM Part Numbers: 12684186 12674704 12636947 213-4223
This is a Hall-effect sensor that reads the rotation of the camshaft. It typically uses a 3-pin connector. The specific part number may vary depending on whether you have the 6.6L L5P Duramax diesel engine or the 6.0L/6.6L gasoline V8 engine.
We Have This Part in Stock
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- GMC Sierra 3500 HD:
- 🛍️ Shop This Part
- What is a Camshaft Position Sensor and Why Does It Fail?
- Choosing the Right Aftermarket Sensor for Your Sierra HD
- Tier 1: OEM & OEM-Equivalent Brands
- Tier 2: Reputable Aftermarket Brands
- A Word of Caution on Budget Brands
- Cost to Replace the Camshaft Position Sensor
- DIY Replacement Tip
- Frequently Asked Questions
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