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603 839 Engine Coolant Reservoir for Ram 2013 to 2018 2500 3500 4500 5500 Cap
$125.39
Sale price
$125.39
Regular price
Available to Order
This 603-839 Engine Coolant Reservoir w/Cap is a replacement engine coolant reservoir with cap compatible with 2013-2018 Ram 2500, 3500, 4500, 5500 models and matches OEM Part# 603-839.
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I needed a forklift part and wasn’t sure which one fit. They asked for the model and serial number, got back to me quickly, and made sure I ordered the right one. Really helpful.
Randy W. — Verified customer
Product Overview
The 603-839 Engine Coolant Reservoir is a direct replacement coolant tank designed to maintain proper coolant levels in 2013-2018 Ram 2500, 3500, 4500, and 5500 trucks. This engine coolant reservoir includes a new cap and is built to withstand the high heat and pressure of diesel and gas engine cooling systems. It’s an essential component for fleet operators, diesel mechanics, and Ram owners needing a reliable coolant reservoir that prevents leaks and overheating.
Key Features & Performance
- Includes a new pressure cap for a complete seal
- High-density polyethylene construction resists cracking and heat deformation
- Matches OEM fitment and mounting points for easy installation
- Translucent tank allows quick visual coolant level checks
- Maintains proper system pressure to prevent coolant boiling
- Direct replacement for factory part #603-839
Fitment & Compatibility
- 2013-2018 Ram 2500
- 2013-2018 Ram 3500
- 2013-2018 Ram 4500
- 2013-2018 Ram 5500
- Fits diesel and gasoline engine models originally equipped with coolant reservoir part #603-839
Common Uses
- Replacing a cracked, leaking, or damaged original coolant reservoir
- Restoring cooling system pressure and preventing coolant loss
- Used in routine maintenance or cooling system overhauls on Ram heavy-duty trucks
- Ideal for fleet vehicles, commercial trucks, and personal use trucks
- Prevents overheating and potential engine damage from low coolant levels
Technical Specifications
- Part Number(s): 603-839
- Material: High-density polyethylene (HDPE)
- Cap Included: Yes
- Compatible Vehicle Years: 2013-2018
- Compatible Models: Ram 2500, 3500, 4500, 5500
Frequently Asked Questions
Q: Is this coolant reservoir a direct fit for my Ram truck? A: Yes, it is designed to match the factory shape and mounting points for 2013-2018 Ram 2500-5500 models that originally used part #603-839.
Q: Does the reservoir come with a new cap? A: Yes, a new pressure cap is included with the reservoir to ensure a proper seal and correct system pressure.
Product appearance and specifications may vary slightly by batch. Compatibility may vary by serial number. Verify fitment before purchase.