GENUINE GM PARTS 55496258 Exhaust Gas Temperature Egt Sensor

( Brand: Genuine Gm Parts ), ( Manufacturer Part Number: 55496258 ), ( Manufacturer Warranty: 1 Year ), ( Type: Exhaust Gas Temperature )

Review GENUINE GM PARTS Exhaust Gas Temperature Egt Sensor

The **GM 55496258 Exhaust Gas Temperature (EGT) Sensor** is a precision-engineered component designed to monitor the temperature of exhaust gases within a vehicle s emissions system, ensuring optimal performance, compliance with emissions regulations, and protection of critical aftermarket or factory-installed catalytic converters and turbochargers. This high-quality sensor operates by measuring the temperature of exhaust fumes as they exit the engine, providing real-time data to the vehicle s Engine Control Module (ECM) or Powertrain Control Module (PCM). Constructed from durable materials, including a robust stainless-steel housing and a thermocouple junction sealed with corrosion-resistant ceramic or glass, the GM 55496258 is built to withstand extreme heat, vibration, and harsh environmental conditions, making it ideal for high-performance applications, diesel engines, or vehicles equipped with turbochargers or diesel particulate filters (DPFs).

The sensor features a threaded connection, typically designed to fit standard exhaust flanges, ensuring a secure and leak-proof installation. Its internal thermocouple element often composed of materials like nickel-chromium (Type K) or platinum-rhodium alloys delivers accurate temperature readings across a wide range, typically from ambient levels up to 1,200 F (650 C) or higher, depending on the application. This precision is critical for maintaining proper engine efficiency, reducing emissions, and preventing catastrophic failure of downstream components, such as oxygen sensors or catalytic converters, which can be damaged by excessively high exhaust temperatures. For diesel engines, the EGT sensor plays an even more vital role by helping the ECM manage fuel injection timing, turbocharger boost pressure, and exhaust gas recirculation (EGR) to optimize combustion and minimize soot and NOx emissions.

Beyond its functional reliability, the GM 55496258 is engineered for compatibility with a broad range of General Motors vehicles, including diesel-powered models like the Duramax L5P, LML, or L9N engines found in trucks such as the Chevrolet Silverado, GMC Sierra, and GMC Yukon, as well as the Cadillac Escalade. It is also a popular replacement for aftermarket EGT sensors used in performance tuning setups, where enthusiasts rely on accurate temperature feedback to fine-tune engine parameters for maximum power and durability. Whether used in original equipment applications or as an upgrade for modified vehicles, this sensor ensures that the engine operates within safe and efficient parameters, extending the lifespan of the exhaust system and reducing the risk of costly repairs. Its straightforward installation and long-term durability make it a trusted choice for mechanics, fleet operators, and performance tuners seeking a dependable solution for exhaust temperature monitoring.

### **Pros and Cons of buying a GM 55496258 Exhaust Gas Temperature (EGT) Sensor**

1. **Direct Compatibility** This sensor is specifically designed for General Motors applications, ensuring a proper fit and function without modification. It is commonly used in diesel engines, particularly in older GM models like the Duramax (LLY, LMM, LML) and some Chevrolet/GMC trucks and SUVs.

2. **Reliable Performance** GM s OEM sensors are built to meet strict manufacturing standards, reducing the likelihood of premature failure compared to aftermarket alternatives that may vary in quality.

3. **Warranty Coverage** Purchasing directly from GM or an authorized dealer may include a warranty, providing peace of mind against defects in materials or workmanship.

4. **Accurate Readings** A properly functioning EGT sensor ensures accurate exhaust gas temperature monitoring, which is critical for engine protection, emissions compliance, and optimal performance in diesel applications.

5. **Ease of Installation** Being an OEM part, it is designed to integrate seamlessly with the vehicle s wiring and mounting points, reducing the risk of installation errors.

6. **Long-Term Durability** GM sensors are typically constructed with materials that withstand high temperatures and harsh engine environments, leading to extended service life under normal operating conditions.

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1. **Higher Cost** OEM sensors are generally more expensive than aftermarket equivalents. The price may be a barrier for budget-conscious buyers, especially if the sensor is not under warranty.

2. **Potential Overkill for Some Applications** If the vehicle is not experiencing EGT-related issues (e.g., faulty sensor, code P0030/P0031, or engine protection activations), replacing it with an OEM part may be unnecessary, leading to wasted expenditure.

3. **Limited Availability** Depending on the region or dealer network, finding the exact GM part number (55496258) may require ordering from a specialty auto parts supplier, which could involve shipping delays.

4. **Mixed Reviews on Aftermarket Alternatives** While OEM is reliable, some aftermarket sensors (e.g., from brands like Bosch, Delphi, or Mopar) offer comparable performance at a lower cost. However, quality can vary, so research is advised.

5. **Potential for Counterfeit Parts** Purchasing from untrusted sellers (e.g., unverified online marketplaces) risks receiving fake or low-quality replicas that fail prematurely.

6. **Diagnostic Steps May Be Overlooked** Before replacing the sensor, a thorough diagnosis (e.g., checking for wiring issues, corrosion, or other sensor-related codes) might reveal that the problem lies elsewhere, making the replacement redundant.

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### **Conclusion**

The GM 55496258 EGT sensor is a high-quality, reliable choice for vehicles requiring an OEM replacement, particularly in GM diesel applications where accuracy and durability are critical. Its advantages in compatibility, warranty, and performance justify the higher cost for those who prioritize long-term reliability and peace of mind. However, for buyers on a tight budget or those unsure whether the sensor is truly faulty, exploring aftermarket alternatives (with reputable brands) or verifying the need for replacement through diagnostics may be more cost-effective.

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### **Recommendation**

- You have confirmed through diagnostic trouble codes (e.g., P0030, P0031, P0171, P0174) that the EGT sensor is faulty.

- You are replacing it as part of a scheduled maintenance or warranty-covered repair.

- You prioritize OEM quality and long-term reliability over cost savings.

- The sensor is not confirmed as the root cause of the issue (perform a thorough diagnosis first).

- You are open to aftermarket sensors from trusted brands (e.g., Bosch 0 261 231 000, Delphi D45T, or Mopar 55496258 equivalents) that offer similar performance at a lower price.

- You are purchasing from a reputable dealer or online retailer (e.g., RockAuto, AutoZone, or local GM service centers) to avoid counterfeit parts.

- Always clean the sensor s mounting area and wiring connections during installation to prevent future issues.

- If the sensor is part of an engine protection system (e.g., in Duramax engines), ensure the replacement is installed correctly to avoid triggering false protection modes.

- Keep receipts and warranties in case of early failure, as some OEM parts may qualify for extended coverage.

Details:

This part fits vehicles made in the following years 2014 ,2015. Genuine GM Parts.

part #: 55496258 prices

• $86.79-$86.99

specifications emissyste:

• brand: Genuine Gm Parts
• mpn: 55496258
• manufacturer warranty: 1 Year
• type: Exhaust Gas Temperature

payments emissyste:

• wallet: Apple-pay
• credit card: Diners-club
• other

offer emissyste:

• quantity: 3
• started: March 10, 2026
• options: Ship-to-home
• sold: 0
• availability: In Stock

seller emissyste:

• city: Chattanooga, Tennessee
• # reviews: 54432
• rating: 99.2%

returns emissyste:

• time: 30 Days
• policy: Returns Accepted
• paid by: Seller

shipping emissyste:

• service: UPS Ground Saver
• class: Economy
• carrier: UPS
• cost: $0.00
• transit: 3-7 Days
• type: Fixed

general emissyste:

• Car Truck Parts Accessories > Exhaust Emission Systems > Other Exhaust Emission Parts
• condition: New

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