Moroso 63779 Coolant Expansion Tank for 2006-2015 Mazda Miata

Vehicle Fitment

• 2006-2015 Mazda Miata (NC, All Trims, 1.8L I4)

Features

• Direct bolt-in replacement for the factory coolant expansion tank
• Fabricated aluminum construction for improved durability and strength
• Billet aluminum neck accepts the factory SAE Type B/43 mm radiator cap
• Can be polished, chromed, powder coated, or used as-is
• Improved coolant capacity over stock plastic tanks
• Resists high heat and repeated thermal cycles without cracking
• Integral hose fittings and mounting brackets for proper installation
• Lightweight yet robust design ideal for street or track use

Specifications

• Material: Fabricated aluminum
• Fitment: Front engine bay coolant expansion tank
• Compatibility: Mazda MX-5 Miata 2006-2015
• Accepts factory 43 mm radiator cap (not included)
• Direct bolt-in design - no modification required
• Corrosion-resistant finish
• OEM mounting points retained
• Prop 65 warning: contains chemical known to cause cancer/birth defects

Included Components

• 1x Moroso Coolant Expansion Tank (Part 63779)
• Billet aluminum filler neck (pre-installed)
• Integral hose fittings and mounting brackets

Product Description

The Moroso 63779 Coolant Expansion Tank is a direct bolt-in replacement designed specifically for the 2006-2015 Mazda Miata (NC) to improve the reliability and longevity of your engine cooling system. Factory plastic expansion tanks on these models are prone to cracking and discoloration after years of repeated heat cycles; this fabricated aluminum unit offers a far more durable solution.

Constructed from high-quality aluminum with an integrated billet neck that accepts the factory 43 mm radiator cap, this expansion tank provides enhanced coolant capacity and resistance to heat and pressure compared to the stock component. Its direct bolt-in design uses existing mounting points and hose connections, making installation straightforward without the need for modifications. The natural finish can be polished, chromed, or powder coated to match your engine bay aesthetic.

This Moroso tank is ideal for daily drivers seeking improved durability over the OEM part, performance enthusiasts who want a more reliable cooling setup, or Miata restorers updating aging components. Fitment is confirmed through 2015; 2025 fitment is unconfirmed at time of listing.