Description
The Mishimoto MMFT-HH-5858-90 heater hose fitting set is a direct-fit, CNC-machined aluminum replacement for the quick-disconnect heater hose fittings found on the 2011+ Dodge Durango and Jeep Grand Cherokee. Those factory fittings are molded from brittle plastic that cracks under heat and pressure, dumping coolant and leaving drivers stranded; this Mishimoto Fabrication set corrects that failure point without requiring a full heater hose assembly replacement or a trip through the firewall.
Failure on these vehicles typically strikes when the engine is heat-soaked from extended idling and then hit with a pressure spike during hard acceleration — exactly the scenario these black 6061 aluminum fittings are built to survive. Machined in aluminum rather than molded in plastic, each fitting pairs with double FKM O-rings to hold a leak-free seal under pressure, and the improved-design grade type is engineered to resist the repeated heat cycling that dooms the factory part. Because the fix only requires basic hand tools and doesn’t involve routing hose through the firewall, it’s a straightforward way to permanently address a well-documented weak point in the factory cooling system while keeping the rest of the heater hose assembly intact.
Vehicle Applications
This fitting set is built for the Dodge Durango from 2011 through 2025, covering trims such as Citadel, Citadel Platinum, Crew, Crew Luxe, Crew Plus, Enforcer, GT, Limited, Pursuit, R/T, R/T Hemi Orange, R/T Plus, R/T Premium, Special Service, SRT, SXT, and base Durango models, with exact year coverage varying by trim. It also fits the Jeep Grand Cherokee from 2011 through 2021, including 80th Anniversary, Blindada, High Altitude, Laredo, Laredo X, Limited, Limited Lujo, Limited Lujo Advance, Limited Lujo V8, Limited Premium, Limited X, Overland, Overland Summit, SRT, SRT8, Summit, Summit Elite Platinum, Trailhawk, and base Grand Cherokee models, again depending on the specific model year and trim.
Features
- Direct-fit replacement for the 2011+ Dodge Durango and Jeep Grand Cherokee
- Replaces the brittle plastic factory fitting with durable aluminum designed to resist repeated heat cycles
- Installation is simple and straightforward without having to go through the firewall
- Double FKM O-rings ensure leak-free performance under high pressure
- Prevents coolant dumping and breakdowns during sudden acceleration
- Backed by the Mishimoto Lifetime Warranty
- Includes (2) fittings, (4) O-rings, and (2) worm gear clamps
Specifications
- Material: 6061 Aluminum
- Color: Black
- Inlet: 5/8″ SAE Quick-disconnect Female
- Outlet: 5/8″ Hose barb Male
- Fitting Angle: 90 degrees
- End 1 Inside Diameter: 0.625 in
- End 2 Inside Diameter: 0.625 in
- Maximum Bend Angle: 90 degrees
- Maximum Working Pressure: 50 PSI
- Max Fluid Pressure: 50 PSI
- Max Fluid Temperature: 400°F
- Compatible Fluids: Air, Coolant, Gas, Oil, Transmission Fluid, Water
- Hose Shape: Molded Assembly
- Grade Type: Improved Design
- Clamps Included: Yes
- Contains Spring: No
- Protective Sleeve Attached: No
- Includes: (2) Fittings, (4) O-Rings, (2) Worm Gear Clamps, Mishimoto Lifetime Warranty
Frequently Asked Questions
What vehicles fit the Mishimoto MMFT-HH-5858-90 heater hose fitting set?
It is designed for the 2011–2025 Dodge Durango and the 2011–2021 Jeep Grand Cherokee across the trims listed in the vehicle applications section, with exact year coverage varying by trim.
Why does the factory heater hose fitting fail?
The stock quick-disconnect fittings on these vehicles are made from brittle plastic that cracks under heat and pressure. Failure typically happens when the engine is heat-soaked from extended idling and then sees a pressure spike during hard acceleration.
Does installing this fitting set require going through the firewall?
No. Installation is simple and straightforward and does not require going through the firewall or replacing the entire heater hose assembly.
What is included in the kit?
The kit includes (2) fittings, (4) O-rings, and (2) worm gear clamps, and it is backed by the Mishimoto Lifetime Warranty.
What is the maximum working pressure and temperature these fittings can handle?
The fittings have a maximum working pressure of 50 PSI and a maximum fluid temperature of 400°F.
What materials and sealing components are used?
The fittings are machined from black 6061 aluminum and use double FKM O-rings to ensure leak-free performance under pressure.
⚠ WARNING (California Proposition 65): This product can expose you to chemicals known to the State of California to cause cancer and/or birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.
