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Dorman 603-844 Engine Coolant Reservoir
Overview of Dorman Engine Coolant Reservoir 603-844
The Dorman Engine Coolant Reservoir 603-844 is designed to maintain optimal coolant levels in Ford Transit vehicles. This clear plastic reservoir features a twist cap and pressurized design to support efficient engine cooling.
- Material: Durable clear plastic for easy coolant level monitoring
- Capacity: 6.3 quarts to accommodate cooling system needs
- Dimensions: 12 inches length and 9.5 inches height with a circular shape
- Mounting: Includes mounting brackets and two mounting holes for secure installation
- Cap: Twist type cap included with a maximum pressure rating of 21 psi
- Pressurized reservoir to maintain system pressure and prevent coolant loss
Detailed Product Description
This engine coolant reservoir by Dorman is engineered specifically for Ford Transit models including Transit, Transit-150, Transit-250, Transit-350, and Transit-350 HD. Constructed from clear plastic, it allows for quick visual inspection of coolant levels without removal. The circular shape and included mounting brackets ensure a proper fit and secure attachment within the engine bay. The twist cap is designed to maintain a pressurized environment up to 21 psi, which helps prevent overheating and coolant evaporation. Although the reservoir does not include a level sensor, it is compatible with existing vehicle sensors and systems.
Common Applications and Problem Resolution
- Replacement for cracked or leaking coolant reservoirs in Ford Transit vehicles
- Restores proper coolant containment to prevent engine overheating
- Addresses coolant loss due to damaged or faulty reservoirs
- Helps maintain system pressure for efficient engine cooling
- Supports coolant level monitoring with clear plastic construction
Installation Notes and Tips
Before installation, ensure the engine is cool to avoid injury from hot coolant. This reservoir includes mounting brackets but does not come with additional mounting hardware, so verify existing hardware condition. The twist cap should be securely tightened to maintain system pressure. Check for any leaks after installation and refill the cooling system as needed according to manufacturer specifications.
Quality Assurance and Warranty
Dorman parts are manufactured to meet or exceed OEM standards for fit, form, and function. The 603-844 engine coolant reservoir is made from durable materials designed to withstand typical engine bay conditions. While specific warranty details are not provided here, Dorman generally offers limited warranties on their replacement parts to ensure reliability and customer satisfaction.
| Brand | Dorman |
| Part Number | 603-844 |
| Material | Plastic |
| Length | 12 |
| Color | Clear |
| Mounting Hardware Included | No |
| Height | 9.5 |
| Shape | Circular |
| Mounting Hole Quantity | 2 |
| Mounting Brackets Included | Yes |
| Cap Type | Twist |
| Pressurized | Yes |
| Cap Maximum Pressure Rating | 21 |
| Level Sensor Included | No |
| Cap Included | Yes |
| Capacity | 6.3 qt. |
| Package Contents | 1 coolant reservoir; 1 cap |
This part fits 65 vehicles. Search below:
| Year | Make | Model | Liters | Cylinders | Position | Notes |
|---|---|---|---|---|---|---|
| 2019 | Ford | Transit | 3.7L | V6 | N/A | |
| 2019 | Ford | Transit-150 | 3.5L | V6 | N/A | |
| 2019 | Ford | Transit-150 | 3.7L | V6 | N/A | |
| 2019 | Ford | Transit-150 | 3.2L | L5 | N/A | |
| 2019 | Ford | Transit-250 | 3.5L | V6 | N/A | |
| 2019 | Ford | Transit-250 | 3.7L | V6 | N/A | |
| 2019 | Ford | Transit-250 | 3.2L | L5 | N/A | |
| 2019 | Ford | Transit-350 | 3.5L | V6 | N/A | |
| 2019 | Ford | Transit-350 | 3.7L | V6 | N/A | |
| 2019 | Ford | Transit-350 | 3.2L | L5 | N/A | |
| 2019 | Ford | Transit-350 HD | 3.5L | V6 | N/A | |
| 2019 | Ford | Transit-350 HD | 3.7L | V6 | N/A | |
| 2019 | Ford | Transit-350 HD | 3.2L | L5 | N/A | |
| 2018 | Ford | Transit | 3.7L | V6 | N/A | |
| 2018 | Ford | Transit-150 | 3.5L | V6 | N/A | |
| 2018 | Ford | Transit-150 | 3.7L | V6 | N/A | |
| 2018 | Ford | Transit-150 | 3.2L | L5 | N/A | |
| 2018 | Ford | Transit-250 | 3.5L | V6 | N/A | |
| 2018 | Ford | Transit-250 | 3.7L | V6 | N/A | |
| 2018 | Ford | Transit-250 | 3.2L | L5 | N/A | |
| 2018 | Ford | Transit-350 | 3.5L | V6 | N/A | |
| 2018 | Ford | Transit-350 | 3.7L | V6 | N/A | |
| 2018 | Ford | Transit-350 | 3.2L | L5 | N/A | |
| 2018 | Ford | Transit-350 HD | 3.5L | V6 | N/A | |
| 2018 | Ford | Transit-350 HD | 3.7L | V6 | N/A | |
| 2018 | Ford | Transit-350 HD | 3.2L | L5 | N/A | |
| 2017 | Ford | Transit | 3.7L | V6 | N/A | |
| 2017 | Ford | Transit-150 | 3.5L | V6 | N/A | |
| 2017 | Ford | Transit-150 | 3.7L | V6 | N/A | |
| 2017 | Ford | Transit-150 | 3.2L | L5 | N/A | |
| 2017 | Ford | Transit-250 | 3.5L | V6 | N/A | |
| 2017 | Ford | Transit-250 | 3.7L | V6 | N/A | |
| 2017 | Ford | Transit-250 | 3.2L | L5 | N/A | |
| 2017 | Ford | Transit-350 | 3.5L | V6 | N/A | |
| 2017 | Ford | Transit-350 | 3.7L | V6 | N/A | |
| 2017 | Ford | Transit-350 | 3.2L | L5 | N/A | |
| 2017 | Ford | Transit-350 HD | 3.5L | V6 | N/A | |
| 2017 | Ford | Transit-350 HD | 3.7L | V6 | N/A | |
| 2017 | Ford | Transit-350 HD | 3.2L | L5 | N/A | |
| 2016 | Ford | Transit | 3.7L | V6 | N/A | |
| 2016 | Ford | Transit-150 | 3.5L | V6 | N/A | |
| 2016 | Ford | Transit-150 | 3.7L | V6 | N/A | |
| 2016 | Ford | Transit-150 | 3.2L | L5 | N/A | |
| 2016 | Ford | Transit-250 | 3.5L | V6 | N/A | |
| 2016 | Ford | Transit-250 | 3.7L | V6 | N/A | |
| 2016 | Ford | Transit-250 | 3.2L | L5 | N/A | |
| 2016 | Ford | Transit-350 | 3.5L | V6 | N/A | |
| 2016 | Ford | Transit-350 | 3.7L | V6 | N/A | |
| 2016 | Ford | Transit-350 | 3.2L | L5 | N/A | |
| 2016 | Ford | Transit-350 HD | 3.5L | V6 | N/A | |
| 2016 | Ford | Transit-350 HD | 3.7L | V6 | N/A | |
| 2016 | Ford | Transit-350 HD | 3.2L | L5 | N/A | |
| 2015 | Ford | Transit | 3.7L | V6 | N/A | |
| 2015 | Ford | Transit-150 | 3.5L | V6 | N/A | |
| 2015 | Ford | Transit-150 | 3.7L | V6 | N/A | |
| 2015 | Ford | Transit-150 | 3.2L | L5 | N/A | |
| 2015 | Ford | Transit-250 | 3.5L | V6 | N/A | |
| 2015 | Ford | Transit-250 | 3.7L | V6 | N/A | |
| 2015 | Ford | Transit-250 | 3.2L | L5 | N/A | |
| 2015 | Ford | Transit-350 | 3.5L | V6 | N/A | |
| 2015 | Ford | Transit-350 | 3.7L | V6 | N/A | |
| 2015 | Ford | Transit-350 | 3.2L | L5 | N/A | |
| 2015 | Ford | Transit-350 HD | 3.5L | V6 | N/A | |
| 2015 | Ford | Transit-350 HD | 3.7L | V6 | N/A | |
| 2015 | Ford | Transit-350 HD | 3.2L | L5 | N/A |
* 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.