With screw-on radiator caps, the thread size is everything. Caps that look almost identical can differ by just a couple of millimetres, and the wrong one simply won't seal. The Tridon CW18125 is made for M55 plastic filler necks, giving a precise, full-thread fit that locks in firmly and seals cleanly every time.
Rated at 18 PSI (125 kPa), this plastic recovery cap keeps the cooling system under enough pressure to handle the heat of modern engines, including long highway runs, towing and stop-start summer traffic. Its double-seal design works with the expansion tank, allowing coolant to push out as it heats and flow back as it cools, so the level stays steady and air stays out of the system. In a healthy recovery system, that means you shouldn't need to top up between scheduled services.
If you're finding coolant creeping out, a reservoir level that won't settle, or a cap that's become brittle and hard to turn, it's time for a replacement. Always match the thread size and pressure rating of your original cap, and check fitment for your vehicle before ordering.
- Series - CW
- Pressure - 18 (PSI), 125 (kPa)
- System - Recovery
- Cap Style - Plastic
- Connection Type - Plastic Screw (Suits M55)
