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The Mishimoto In-Line Oil Thermostat, part number misMMOP-EXTFC, offers a reliable solution for maintaining optimal fluid temperatures in automotive applications. Crafted from CNC-machined billet 6061 aluminum, this sleek, compact unit is designed to fit seamlessly into tight spaces where traditional oil sandwich plates may not be feasible. Its streamlined design ensures easy installation and compatibility with a variety of custom projects. The thermostat features a standard operating temperature of 185°F, with interchangeable options available at 160°F and 200°F to suit different performance requirements. This versatility makes it ideal for regulating engine oil, transmission fluid, or other driveline fluids, helping to optimize engine performance and prolong component life. The thermostat includes four -10AN fittings with dowty seals, guaranteeing leak-free connections and dependable operation. Additionally, a CNC-machined heat sink enhances both the aesthetic appeal and thermal management, assisting in reduction of fluid temperatures during operation. The unit also comes with a universal mounting bracket for simplified installation and is backed by Mishimoto's lifetime warranty, reflecting their commitment to quality and craftsmanship. Whether you're upgrading a high-performance build or customizing a unique project, this in-line thermostat provides precise temperature regulation in a compact, durable package. Its universal fitment and modular thermostat options make it a versatile choice for automotive enthusiasts seeking dependable fluid control solutions.
Features:
Order Processing
All orders are processed and shipped within 24 hours of purchase (excluding weekends and holidays).
Orders placed after 3:00 PM EST may ship the following business day.
Shipping Methods
Customers select their preferred shipping method and speed at checkout.
Shipping times are determined by the carrier and cannot be guaranteed by us.
Tracking information will be provided once your order has shipped.
Shipping Coverage
If your package arrives damaged, please notify the delivery driver immediately and contact the shipping carrier to file a claim.
You must report any missing or damaged items within 14 days of delivery.
After this time, we cannot be held responsible for lost or damaged items.
Return Window
You have 30 days from the date of delivery to request a return.
After 30 days, we are unable to accept returns, exchanges, or refund requests.
Eligibility
Items must be returned in their original condition—unused, unwashed, and with all tags and packaging intact.
Certain products may not be eligible for return (e.g., special-order items, customized products, or perishable goods).
Items that have been altered, installed, or modified cannot be returned.
Return Process
Contact our Customer Support team to request a Return Authorization (RMA) before sending items back.
Once your return is approved, you’ll receive instructions on where to send the product.
Customers are responsible for return shipping costs unless the item was defective or incorrect.
Refunds
Refunds are issued to the original payment method once the returned item has been received and inspected.
Please allow 5–10 business days for the refund to appear on your account.
In some cases, a restocking fee may apply (if applicable, this will be disclosed during your return authorization).
