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Remy 20021 Alternator
Reliable Alternator for Ram 2500 and 3500 Vehicles
The Remy Premium Remanufactured Alternator 20021 is designed to restore your Ram 2500 or 3500's electrical charging system with dependable performance. This remanufactured alternator meets strict quality standards and is engineered to match original equipment specifications.
- Amperage Rating: 220 amps for consistent power output
- Internal fan type for efficient cooling
- Remanufactured to OEM standards by Nippondenso
- Includes pulley for straightforward installation
- Clockwise rotation direction compatible with Ram 2500 and 3500 models
- 12-volt system voltage
- External voltage regulator type for reliable voltage control
About the Premium Remanufactured Product Line
The Premium Remanufactured line from Remy offers alternators that have been carefully rebuilt to meet or exceed original equipment manufacturer (OEM) specifications. Each unit undergoes thorough testing and quality checks to ensure durability and performance. This line is ideal for customers seeking a cost-effective alternative to new parts without compromising on reliability, specifically tailored for vehicles like the Ram 2500 and 3500.
Detailed Product Description
This Remy alternator, part number 20021, is a remanufactured unit designed to provide 220 amps of electrical output, suitable for heavy-duty applications in Ram 2500 and 3500 trucks. Featuring an internal fan, it maintains optimal operating temperatures during extended use. The included pulley simplifies replacement, and the clockwise rotation matches the original equipment setup. The external voltage regulator ensures stable voltage delivery to your vehicle’s electrical system, supporting consistent battery charging and electrical component operation.
Common Applications and Issues Addressed
- Restores charging system functionality in Ram 2500 and 3500 trucks
- Resolves battery drain or failure to charge issues
- Eliminates dimming or flickering lights caused by alternator faults
- Replaces noisy or overheating alternators with internal fan cooling
- Corrects voltage irregularities due to faulty voltage regulators
Installation Notes and Tips
When installing the Remy 20021 alternator, ensure the clockwise rotation matches your vehicle’s original alternator. The included pulley allows for direct replacement without additional parts. Verify the external voltage regulator connections are secure and compatible with your Ram 2500 or 3500 model. It is recommended to test the charging system after installation to confirm proper operation.
Quality Assurance and Warranty
Remy’s Premium Remanufactured alternators undergo comprehensive testing to meet OEM standards. Each unit is inspected for electrical output, mechanical integrity, and durability. While specific warranty details may vary, Remy typically offers coverage to protect against defects in materials and workmanship, providing confidence in the part’s reliability for your Ram 2500 or 3500.
| Brand | Remy |
| Part Number | 20021 |
| Position | Premium Remanufactured |
| Amperage Rating | 220 |
| Fan Type | Internal |
| New or Remanufactured | Remanufactured |
| OE Manufacturer | Nippondenso |
| Pulley Included | Yes |
| Rotation Direction | Clockwise |
| Voltage (V) | 12 |
| Voltage Regulator Type | External |
This part fits 24 vehicles. Search below:
| Year | Make | Model | Liters | Cylinders | Position | Notes |
|---|---|---|---|---|---|---|
| 2024 | Ram | 2500 | 6.7L | L6 | N/A | 220 Amps; Premium Remanufactured |
| 2024 | Ram | 3500 | 6.7L | L6 | N/A | 220 Amps; Premium Remanufactured |
| 2023 | Ram | 2500 | 6.7L | L6 | N/A | 220 Amps; Premium Remanufactured |
| 2023 | Ram | 3500 | 6.7L | L6 | N/A | 220 Amps; Premium Remanufactured |
| 2022 | Ram | 2500 | 6.7L | L6 | N/A | 220 Amps; Premium Remanufactured |
| 2022 | Ram | 3500 | 6.7L | L6 | N/A | 220 Amps; Premium Remanufactured |
| 2021 | Ram | 2500 | 6.7L | L6 | N/A | Auxiliary Alt; 220 Amps; Premium Remanufactured |
| 2021 | Ram | 3500 | 6.7L | L6 | N/A | Dual Alt System; Auxiliary Alt; 220 Amps; Premium Remanufactured |
| 2020 | Ram | 2500 | 6.7L | L6 | N/A | Auxiliary Alt; 220 Amps; Premium Remanufactured |
| 2020 | Ram | 3500 | 6.7L | L6 | N/A | Dual Alt System; Auxiliary Alt; 220 Amps; Premium Remanufactured |
| 2019 | Ram | 2500 | 6.7L | L6 | N/A | Dual Alt System; Auxiliary Alt; 220 Amps; Premium Remanufactured |
| 2019 | Ram | 3500 | 6.7L | L6 | N/A | Dual Alt System; Auxiliary Alt; 220 Amps; Premium Remanufactured |
| 2018 | Ram | 2500 | 6.7L | L6 | N/A | Dual Alt System; Auxiliary Alt; 220 Amps; Premium Remanufactured |
| 2018 | Ram | 3500 | 6.7L | L6 | N/A | Dual Alt System; Auxiliary Alt; 220 Amps; Premium Remanufactured |
| 2017 | Ram | 2500 | 6.7L | L6 | N/A | Dual Alt System; Auxiliary Alt; 220 Amps; Premium Remanufactured |
| 2017 | Ram | 3500 | 6.7L | L6 | N/A | Dual Alt System; Auxiliary Alt; 220 Amps; Premium Remanufactured |
| 2016 | Ram | 2500 | 6.7L | L6 | N/A | Dual Alt System; Auxiliary Alt; 220 Amps; Premium Remanufactured |
| 2016 | Ram | 3500 | 6.7L | L6 | N/A | Dual Alt System; Auxiliary Alt; 220 Amps; Premium Remanufactured |
| 2015 | Ram | 2500 | 6.7L | L6 | N/A | Dual Alt System; Auxiliary Alt; 220 Amps; Premium Remanufactured |
| 2015 | Ram | 3500 | 6.7L | L6 | N/A | Dual Alt System; Auxiliary Alt; 220 Amps; Premium Remanufactured |
| 2014 | Ram | 2500 | 6.7L | L6 | N/A | Dual Alt System; Auxiliary Alt; 220 Amps; Premium Remanufactured |
| 2014 | Ram | 3500 | 6.7L | L6 | N/A | Dual Alt System; Auxiliary Alt; 220 Amps; Premium Remanufactured |
| 2013 | Ram | 2500 | 6.7L | L6 | N/A | Dual Alt System; Auxiliary Alt; 220 Amps; Premium Remanufactured |
| 2013 | Ram | 3500 | 6.7L | L6 | N/A | Dual Alt System; Auxiliary Alt; 220 Amps; Premium Remanufactured |
* Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
This part directly replaces or is cross-referenced with the following part numbers:
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.