Heating and Cooling› Overflow Tanks and Catch Cans

Moroso

Fabricated Aluminum Coolant Expansion Tank

$255.00

SKU: 916-386

Special Order
Free Shipping over $200
$100 Minimum Order
Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Easy — 1–2 hours

Overview

The Moroso 916-386 is a fabricated aluminum coolant expansion tank designed as a direct bolt-in replacement for the stock plastic tank. It offers increased capacity and improved heat transfer capabilities compared to the original component. This tank is durable enough to withstand hard use and can be polished, chromed, or powder coated to match your vehicle's aesthetic. It includes a billet aluminum cap with an O-ring for a secure seal.
Show original supplier description
The Moroso 916-386 Aluminum Coolant Overflow Tank is engineered to enhance your vehicle's cooling system performance, especially during demanding driving conditions like track laps or spirited performance driving. Unlike fragile plastic stock tanks, this unit is constructed from durable, fabricated aluminum for superior strength and longevity. This expansion tank provides increased coolant capacity and improved heat transfer, contributing to more efficient engine cooling. The direct bolt-in design ensures a straightforward installation, replacing the factory plastic tank seamlessly. The tank's aluminum construction offers versatility, allowing it to be polished, chromed, or powder coated to customize its appearance or match other engine bay components. It comes complete with a billet aluminum cap featuring an O-ring for a reliable seal. Designed for 1999-2005 Mazda MX-5 Miata (NB series) models, this Moroso tank is a direct replacement, simplifying installation and integration into your existing cooling system.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandMoroso
Part Number916-386
CategoryHeating and Cooling

Videos

MIATA MOROSO COOLANT RESERVOIR | #OMGMIATA | EP84 | [4K60]

MIATA MOROSO COOLANT RESERVOIR | #OMGMIATA | EP84 | [4K60]
Moroso Power Steering Tank Installed on an NC Miata

Moroso Power Steering Tank Installed on an NC Miata

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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