Ignition Knock Sensor Replacement Guide for 2011-2022 Ram 3500 (HEMI)
Keep your HEMI running strong by understanding and replacing a faulty knock sensor.
- Your Ram 3500 with a HEMI engine has two knock sensors located on the sides of the engine block.
- Symptoms of failure include a check engine light (P0325, P0330), engine pinging, power loss, and poor gas mileage.
- For best results, choose a top-tier aftermarket brand like NGK/NTK or Delphi, which are often OEM suppliers.
- It is highly recommended to replace both sensors at the same time to avoid a repeat repair job.
Is Your Ram 3500 Knock Sensor Failing?
A bad knock sensor can cause noticeable problems. The most common sign is the check engine light turning on. You might also hear a metallic pinging or knocking sound from the engine, especially when accelerating or towing. Many owners report a significant loss of power, poor acceleration, and worse fuel economy. This happens because the truck's computer, unable to trust the sensor, will default to a 'safe' mode with reduced engine timing to prevent damage.
🎬 Watch: 5 common symptoms of a failing knock sensorChoosing the Right Aftermarket Knock Sensor
When replacing a critical sensor, brand quality matters. While OEM Mopar parts are a safe bet, several aftermarket brands offer excellent quality, sometimes from the same factory that makes the original part.
| Brand Tier | Brands | General Consensus |
|---|---|---|
| Top Tier (OEM or Equivalent) | NGK, Delphi | NGK (also NTK) and Delphi are often original equipment suppliers for many automakers. They are highly recommended in forums for their reliability and performance, making them a trusted choice. |
| Mid-Tier (Reliable Aftermarket) | Standard Ignition (Standard Motor Products), Walker Products, Holstein | Standard Motor Products (SMP) is a long-standing brand with a generally good reputation, though some users suggest avoiding their budget "T-series" line. These brands are considered reliable replacements that meet or exceed OEM specifications. |
| Economy Tier | Crown Automotive, Global Parts, Beck Arnley | These brands offer a budget-friendly option. However, for sensitive electronic parts like knock sensors, some users report mixed results or early failures with economy brands. Consider these if budget is the primary concern, but be aware of the potential for a shorter lifespan. |
Known Issues for 2011-2022 Ram 3500
Searches for official recalls or Technical Service Bulletins (TSBs) from Ram or the NHTSA did not find any specific issues directly targeting the knock sensors on these trucks. Failures are typically due to age, heat cycles, and exposure to the elements. The location on the side of the engine block can expose the sensor and its wiring to road debris and moisture over time.
Frequently Asked Questions
How many knock sensors does my Ram 3500 have?
If you have a 5.7L or 6.4L HEMI engine, your truck has two knock sensors. One is for each cylinder bank.
Where are the knock sensors located on a Ram 3500 HEMI?
They are not under the intake manifold like on some other engines. On the HEMI V8s in these trucks, the two knock sensors are mounted on the sides of the engine block, below the exhaust manifolds.
🎬 See this video for exact sensor locations and torque specsCan I replace a knock sensor myself?
Yes, this is a feasible DIY job for someone with moderate mechanical skill. Access is from underneath the truck. It involves safely raising the vehicle, locating the sensor, disconnecting the electrical connector, and removing a single bolt. 🎬 Watch this step-by-step guide to replacing the sensor yourself Ensure you torque the new sensor to the correct specification, as over-tightening can damage the new part.
Should I replace both knock sensors at the same time?
It is highly recommended. The sensors are the same age and have been exposed to the same conditions. If one has failed, the other may not be far behind. Replacing both at once saves you from having to do the job a second time.
Helpful Videos
Technical Specifications
OEM Part Numbers: 68570138AA 5033316AB
For 2011-2022 Ram 3500 with 5.7L or 6.4L HEMI V8 engines. Two sensors are required for a complete replacement.
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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.
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- 🎬 Helpful Videos
- 🛍️ Shop This Part
- Is Your Ram 3500 Knock Sensor Failing?
- Choosing the Right Aftermarket Knock Sensor
- Known Issues for 2011-2022 Ram 3500
- How many knock sensors does my Ram 3500 have?
- Where are the knock sensors located on a Ram 3500 HEMI?
- Can I replace a knock sensor myself?
- Should I replace both knock sensors at the same time?
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