A-Premium Engine Coolant Overflow Reservoir with Sensor & Cap for BMW E46/E83 – 6-Cyl 2.2-3.0L | 603-535

Enhance your BMW cooling system with a reliable replacement

The A-Premium Engine Coolant Overflow Reservoir with Sensor & Cap is designed as a sturdy, ready-to-install replacement for select BMW models. Crafted to endure heat and vibration, this reservoir helps maintain consistent coolant levels and supports smooth engine operation, even on longer drives or daily commutes.

Built for the needs of DOHC, 6-cylinder engines ranging from 2.2 to 3.0 liters, this reservoir integrates a sensor and a spring-loaded cap for precise monitoring and secure sealing. The combination helps you stay informed about coolant status and helps prevent spill or loss during pressure fluctuations in the cooling system.

Key specifications you can rely on

• Material: PA plastic designed to withstand heat and vibration, contributing to long-term durability.
• Cap & Sensor: Includes a spring-loaded twist cap and an integrated sensor for efficient monitoring.
• Dimensions: Height 359.7 mm; Length 121.3 mm; Width 133.4 mm, providing a compact fit in designed spaces.
• Mounting: 1 mounting hole for straightforward installation with a clamp included.

In daily use, you might notice steadier coolant levels and a more consistent response from your heating system, especially during cooler starts and heat soak scenarios. While not a guarantee, such a replacement can contribute to maintaining steady cooling performance and overall engine efficiency, particularly if you are restoring or maintaining BMW models from the early 2000s.

Fitment overview

Designed for a range of BMWs, including: E46 320i (2001–2005) 2.2L, 323Ci (2000) 2.5L, 323i (1999–2000) 2.5L, 325Ci (2001–2006) 2.5L, 325i/325xi (2001–2005) 2.5L, 328Ci (2000) 2.8L, 328i (1999–2000) 2.8L, 330Ci (2001–2006) 3.0L and the E83/E53 X3 (2004–2010) 2.5L/3.0L, X5 (2001–2006) 3.0L. Reference numbers include 603-535 and 17137787039 among others for cross-compatibility.

What you get

• 1 x reservoir
• 1 x cap
• 1 x sensor
• 1 x clamp

Quality assurance

Backed by a 1-year unlimited-mileage quality guarantee, this replacement is positioned as a sturdy, brand-new addition to support your BMW’s cooling system.