Heating and Cooling› Oil and Fluid Coolers

Mishimoto

Thermostatic Oil Cooler Kit

$833.00

SKU: MMOC-MIA-99BK

In Stock
In Stock
Ships by Sep 12
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

The Mishimoto MMOC-MIA-99BK is a thermostatic oil cooler kit designed for the 1999-2005 Mazda Miata NB. It replaces the factory liquid-to-liquid oil cooler to improve efficiency and reduce oil temperatures. This kit features a 19-row stacked-plate oil cooler that increases oil capacity by 0.75 quarts.
Show original supplier description
The Mishimoto Thermostatic Oil Cooler Kit is engineered as a direct fit for the 1999-2005 Mazda Miata NB, addressing the limitations of the stock liquid-to-liquid oil cooler during spirited driving or track use. This kit effectively replaces the OEM cooler, enhancing overall efficiency and significantly reducing oil temperatures. During testing, this setup demonstrated a reduction of 10°F (5.6°C) in oil temperatures, even during highway cruising. Constructed with a 19-row stacked-plate oil cooler, this kit also increases the oil capacity by 0.75 quarts, further contributing to improved cooling performance. The design incorporates mounting brackets that double as ducting to channel air directly to the cooler, optimizing airflow. The billet aluminum thermostatic oil sandwich plate ensures that the oil reaches its optimal operating temperature before circulating through the cooler, which is crucial for preventing overcooling, especially in colder climates. The kit includes pre-made stainless steel braided lines with durable -10AN fittings and is backed by the Mishimoto Lifetime Warranty. This oil cooler is available in two finishes: Sleek Silver and Stealth Black. For daily-driven vehicles, the thermostatic option is recommended to manage oil temperature more effectively. The product is listed for applications including the 1999-2003 Mazda Miata Base and 2000-2003 Mazda Miata LS, alongside various Ford Mustang models (2018-2021).

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

BrandMishimoto
Part NumberMMOC-MIA-99BK
CategoryHeating and Cooling

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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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