ApplianPar Aluminum Thermostat Housing & Water Outlet for 4.0L V6 Ford (Explorer/Ranger) — Direct-Fit, Corrosion-Resistant

ApplianPar's aluminum thermostat housing and water outlet is a direct-replacement cooling system component designed to fit specific Ford, Mercury, and Mazda 4.0L V6 models.

This single-piece engine coolant thermostat housing and water outlet is cast from aluminum to provide reliable coolant routing and a direct fit where original parts have worn or cracked. It replaces several factory part numbers and is made for easy installation on compatible 4.0L V6 vehicles, restoring coolant flow and sealing where the OEM housing has failed.

Which vehicles does this housing fit and which part numbers does it replace?

This thermostat housing is engineered to match factory dimensions for a precise fit on the listed engines and years. It is compatible with multiple Ford, Mercury, and Mazda platforms that use the 4.0L V6 layout.

• Replaces part numbers: 4L5E-8594-AA, 4L5E-8A586-BB, 4L5E-8A586-AB, 2L5Z-8592-BB, 4L5Z-8592-AA, 2L5Z-8592-BA.
• Fits Ford Explorer 4.0L V6 (2001–2005) and Ford Ranger 4.0L V6 (2001–2011).
• Compatible with Mazda B4000 4.0L V6 (2001–2008) and 2001 Mercury Mountaineer 4.0L V6.

How does the aluminum construction affect performance and durability?

Aluminum offers a corrosion-resistant alternative to some plastic housings and can better withstand heat cycles common in engine bays. A metal housing reduces the likelihood of cracks or deformation over time compared with aging plastic parts.

• Aluminum casting resists warping from engine heat.
• Improved longevity compared with brittle plastic housings.
• Maintains factory coolant routing and mounting points for secure sealing.

What comes in the package and what should I prepare for installation?

The product ships as a single engine coolant thermostat housing and water outlet designed for direct replacement of the OEM unit. Basic hand tools, a new gasket or sealant, and coolant are typically needed to complete the swap safely.

• Package includes: 1 × engine coolant thermostat housing (water outlet).
• Recommended to use a new thermostat gasket or proper RTV sealant.
• Have coolant and bleeding procedure ready for refilling the system after installation.

Will this housing cause changes to engine cooling or require other modifications?

When installed correctly, this housing restores the original coolant path and should not alter engine temperature behavior. It is a like-for-like replacement intended to match OEM fit and function without additional modifications.

• Designed to match OEM mounting points and hose connections.
• Does not require changes to thermostat or radiator components unless those parts show wear.
• Use OEM-equivalent clamps and hoses for a secure installation.

Who is this for: This ApplianPar aluminum thermostat housing is aimed at owners or technicians working on Ford Explorer, Ford Ranger, Mazda B4000, or 2001 Mercury Mountaineer vehicles with the 4.0L V6 who need a durable, direct-replacement water outlet. It’s appropriate for DIY mechanics seeking a straightforward swap as well as professional shops replacing failed or leaking housings to restore coolant integrity and prevent overheating issues related to failed housings.