Important Fitment Exclusions
This hose kit does not fit:
- 1997–2002 Wrangler with the 2.5L four-cylinder
- 2003–2006 Wrangler with the 2.4L four-cylinder
- 1987–1995 Wrangler YJ
- 2007 or newer Wrangler JK
- Cherokee XJ or Grand Cherokee models
- Custom engine-swap applications without further measurement
Product Specifications
- Brand: Mishimoto
- Part number: MMHOSE-WR6-97BK
- Product type: Silicone radiator hose kit
- Color: Black
- Material: Reinforced high-grade silicone
- Engine compatibility: 4.0L/242ci inline-six
- Hoses included: Two
- Hose positions: Upper and lower radiator hoses
- Inside diameter: Approximately 1.48 inches
- Outside diameter: Approximately 1.88 inches
- Maximum temperature: 330°F
- Warranty: Mishimoto Lifetime Warranty
Clamp inclusion varies between retailer listings. Confirm the package contents before ordering rather than assuming new clamps are supplied.
What Comes in the MMHOSE-WR6-97BK Kit?
The kit includes:
- One upper radiator hose
- One lower radiator hose
This package replaces the main hoses connecting the engine and radiator. It does not include heater-core hoses, bypass hoses, overflow lines, thermostat, water pump or radiator cap.
Reinforced Silicone Construction
Mishimoto constructs these hoses from high-grade silicone combined with heat-resistant reinforcing fibers. The layered design helps the hoses maintain their shape as coolant temperature and pressure change.
Compared with deteriorated factory rubber hoses, reinforced silicone offers improved resistance to:
- Heat cycling
- Cooling-system pressure
- Cracking and hardening
- Swelling caused by age
- Hose collapse
- Ozone exposure
- Coolant leakage around weakened sections
The black finish preserves a mostly factory-style appearance. That makes it suitable for owners who want better hose construction without turning the engine compartment into a collection of fluorescent pool noodles.
Lower Radiator Hose Trimming May Be Required
Mishimoto notes that the original lower radiator hose can vary in length across these Wrangler applications. Some installations may require trimming the new lower hose for correct fitment.
Before cutting:
- Compare the Mishimoto hose with the original.
- Test-fit both ends without clamps.
- Confirm the hose follows the original path.
- Check clearance around the fan, belt, pulleys and steering components.
- Mark the minimum amount that must be removed.
- Cut the end squarely using an appropriate hose-cutting tool.
- Clean away all debris before installation.
Remove material gradually. A hose that is slightly too long can still be corrected. A hose cut too short becomes an expensive silicone conversation piece.
Why Replace Wrangler Radiator Hoses?
The radiator hoses on an older TJ operate under heat, pressure and constant engine movement. Off-road use adds dirt, vibration, abrasion and low-speed operating conditions that can increase cooling-system stress.
Replace the hoses if you find:
- Surface cracks
- Bulging or swollen sections
- Soft or spongy material
- Hardened ends
- Coolant residue near a connection
- Abrasion from nearby components
- Collapse of the lower hose
- Unexplained coolant loss
- Overheating during low-speed driving
- Coolant odor after shutting off the engine
A hose can leak only while the system is hot and pressurized. Our guide on how to find a coolant leak explains how to inspect the entire cooling system without immediately blaming the most expensive component.
Compatible With Factory and Aluminum Radiators
The MMHOSE-WR6-97BK can be used with the original-style radiator or a compatible aftermarket aluminum radiator when the inlet and outlet locations retain factory dimensions.
An aluminum radiator does not guarantee automatic fitment. Verify:
- Inlet and outlet diameters
- Connection locations
- Fan and shroud clearance
- Hose routing
- Thermostat-housing orientation
- Lower-hose length
Custom radiators or swapped engines may require universal hoses or custom plumbing.
Installation Notes
Never disconnect a radiator hose or remove the pressure cap while the engine is hot. Pressurized coolant can cause severe burns.
Typical installation involves:
- Allowing the engine to cool completely.
- Draining the coolant into an approved container.
- Removing the existing upper and lower hoses.
- Cleaning corrosion from each connection.
- Comparing the new hoses with the originals.
- Trimming the lower hose if required.
- Installing suitable clamps behind each fitting bead.
- Checking for kinks and moving-component interference.
- Refilling with the correct coolant mixture.
- Bleeding trapped air from the cooling system.
- Pressure-testing and inspecting the connections.
Avoid overtightening the clamps. Excessive clamp force can damage silicone or deform a radiator neck.
If the existing coolant is contaminated or its type is unknown, review our guide on how to flush a car cooling system before refilling the Jeep.
Will Silicone Hoses Prevent Overheating?
Silicone hoses can prevent coolant loss and restrictions caused by deteriorated rubber hoses. They do not increase radiator capacity or repair unrelated cooling problems.
A Wrangler can still overheat because of:
- Low coolant
- Trapped air
- Failed thermostat
- Worn water pump
- Clogged radiator
- Damaged fan clutch
- Missing fan shroud
- Incorrect coolant mixture
- Cylinder-head or head-gasket trouble
If the engine runs colder than expected and stores a thermostat-related fault, our P0128 diagnostic guide explains how to check coolant level, thermostat operation and temperature-sensor data.
Frequently Asked Questions
What year Jeep Wrangler does MMHOSE-WR6-97BK fit?
It fits 1997–2006 Jeep Wrangler TJ models equipped with the 4.0L inline-six. It also fits 2004–2006 Wrangler Unlimited LJ models with the same engine.
Does it fit a four-cylinder Wrangler?
No. It is not designed for the 2.5L or 2.4L four-cylinder engines.
Does it fit the Wrangler Rubicon?
Yes. It fits 2003–2006 Wrangler Rubicon models with the 4.0L inline-six. It also fits applicable 2005–2006 Unlimited Rubicon models.
How many hoses are included?
The kit contains two hoses: one upper radiator hose and one lower radiator hose.
Are heater hoses included?
No. This is a primary radiator hose kit, not a complete heater and ancillary hose package.
Will the lower hose require trimming?
Possibly. Mishimoto notes that OE lower-hose length can vary, so some applications may require careful trimming.
Are clamps included?
Retailer information is inconsistent. Confirm the package contents with the seller. If clamps are not included, use correctly sized clamps compatible with reinforced silicone hose.
What is the maximum temperature rating?
Mishimoto lists the maximum temperature at 330°F.
Does it fit an automatic or manual transmission?
Catalog applications cover 4.0L TJ models with several factory automatic and manual transmissions. Confirm the hose routing and radiator configuration before installation.
Official specifications and the trimming note are available on the Mishimoto MMHOSE-WR6-97BK product page.
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