Mishimoto MMRT-F2D-99EN Raw Aluminum Degas Tank 1999-2003 Ford 7.3L Powerstroke

Vehicle Fitment

• 1999-2003 Ford F-250 Super Duty (5.4L V8, 6.8L V10, 7.3L V8 Diesel / Powerstroke)
• 1999-2003 Ford F-350 Super Duty (5.4L V8, 6.8L V10, 7.3L V8 Diesel / Powerstroke)
• 1999-2004 Ford F-250 Super Duty (5.4L V8, 6.8L V10)
• 1999-2004 Ford F-350 Super Duty (5.4L V8, 6.8L V10)
• 1999-2004 Ford F-450 Super Duty (6.8L V10, 7.3L V8 Diesel)
• 1999-2004 Ford F-550 Super Duty (6.8L V10, 7.3L V8 Diesel)
• 1999-2003 Ford Excursion (7.3L V8 Diesel / Powerstroke)
• 1999-2005 Ford Excursion (5.4L V8, 6.8L V10)

Fitment Notes

• This is the natural (raw) aluminum finish variant. The micro-wrinkle black powder-coated variant is available as MMRT-F2D-99EMWBK. Both are otherwise identical in construction and fitment.
• The natural finish is intended for owners who plan to apply a custom finish - powder-coating, anodizing, or hydro-dipping are all compatible. Mishimoto does not provide these services; the customer must source them independently. The natural finish may show minor surface imperfections that will not affect the outcome of powder-coating or other customization processes.
• Fitment is platform-based (Ford Super Duty / Excursion body-on-frame chassis 1999-2004/2005) - covers gasoline (5.4L V8, 6.8L V10) and diesel (7.3L Powerstroke) engine variants that share the same degas tank mounting location and hose connections.
• Fits with the stock degas tank cap - no cap replacement is required.
• The 1/8" NPT port ships with a pre-installed plug. Remove the plug to install an optional coolant pressure sensor - useful for monitoring cooling system pressure on modified or high-mileage 7.3L Powerstroke applications.
• After installation, Mishimoto recommends checking the sight glass after the first few heat cycles to confirm proper coolant level before returning to normal operation.
• Installation difficulty rated Easy. Official Mishimoto PDF installation guide available for download.

Features

• Direct OEM-fit aluminum replacement degas (coolant expansion) tank engineered for the 1999-2004 Ford Super Duty and 1999-2005 Excursion platform - eliminates the stock plastic tank's two primary failure modes: structural cracking from repeated thermal cycling and opaque discoloration that makes coolant level impossible to check visually.
• Full aluminum, fully-welded construction provides permanent resistance to the cracking and leaking that characterizes aged plastic degas tanks on these trucks. On the 7.3L Powerstroke in particular, a failed or leaking degas tank can lead to air introduction into the cooling system, causing overheating and accelerated head gasket wear on a platform sensitive to cooling system integrity.
• 43% increase in coolant capacity over the stock degas tank - the larger aluminum tank holds more coolant in the expansion circuit, providing increased thermal mass and reducing the risk of air ingestion during heat cycles on modified or high-mileage engines.
• Integrated sight glass provides an immediate visual read of coolant level without removing the cap or illuminating the tank - a direct solution to the core usability failure of the stock plastic tank, which becomes opaque and discolored over time, making level checks impossible without partial disassembly.
• Additional 1/8" NPT port (pre-installed plug included) allows for optional installation of a coolant pressure sensor or pressure monitoring gauge - a valuable diagnostic port for 7.3L Powerstroke owners managing aging cooling systems or elevated performance applications.
• Raw natural aluminum finish (this SKU) is ideal for owners planning custom finishing - the uncoated surface accepts powder-coating, anodizing, and hydro-dipping without surface preparation issues. For a ready-to-install finished look, the micro-wrinkle black variant (MMRT-F2D-99EMWBK) is available.
• Installation difficulty rated Easy. Backed by the Mishimoto Lifetime Warranty.

Specifications

• Material: Aluminum, fully-welded construction
• Finish: Natural / raw aluminum (this SKU: MMRT-F2D-99EN) - customization-ready
• Fluid Capacity: 0.72 gal (2.875 qt) - 43% increase over stock
• Sight Glass: Integrated
• Additional Port: 1/8" NPT (pre-installed plug included)
• Cap: Uses stock cap (not included)

Included Components

• 1x Raw aluminum expansion (degas) tank with integrated sight glass
• 1x Pre-installed 1/8" NPT plug
• Mishimoto Lifetime Warranty

Product Description

The Mishimoto MMRT-F2D-99EN is a direct OEM-fit aluminum degas tank engineered for the 1999-2004 Ford Super Duty (F-250 through F-550) and 1999-2005 Ford Excursion, covering all engine variants on the platform including the 7.3L Powerstroke turbodiesel, 5.4L V8, and 6.8L V10. The degas tank - also called the coolant expansion or overflow reservoir - is a critical component of the pressurized cooling system on these trucks, providing controlled volume for coolant expansion and contraction across heat cycles, maintaining system pressure, and enabling coolant level monitoring. The factory unit is injection-molded plastic that performs well when new but becomes brittle, discolored, and prone to cracking after years of repeated thermal cycling and UV exposure. By the time many of these trucks reach high mileage, owners have replaced the factory degas tank multiple times - a pattern Mishimoto set out to permanently eliminate with an aluminum solution.

The Mishimoto aluminum tank is constructed from fully-welded aluminum that will not crack, will not cloud, and will not become brittle from heat cycling. The tank holds 43% more coolant than the stock unit, providing increased expansion volume and thermal mass in the cooling circuit. An integrated sight glass provides an immediate visual read of coolant level from outside the tank - eliminating the need to shine a light through an opaque plastic wall, which is the only way to check level on an aged factory tank. A pre-installed 1/8" NPT port is included for optional coolant pressure sensor installation, particularly useful for monitoring cooling system health on high-mileage or modified 7.3L Powerstroke trucks where cooling system pressure is a key diagnostic indicator. The tank is compatible with the stock degas cap, requiring no cap replacement.

This SKU is the natural raw aluminum finish, specifically chosen by owners who plan to apply a custom coating - the surface accepts powder-coating, anodizing, and hydro-dipping without pre-treatment issues. Mishimoto does not provide these finishing services; they must be sourced independently. Minor surface imperfections may be visible on the raw finish but will not affect the quality of any applied coating. For a ready-to-install finish without any additional work, the micro-wrinkle black powder-coated variant is available as MMRT-F2D-99EMWBK. After the first few heat cycles, confirm proper coolant level via the sight glass before returning to normal operation. Covered by the Mishimoto Lifetime Warranty.