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Denso 221-9558 Radiator
Denso 221-9558 Radiator for Acura RDX
The Denso 221-9558 radiator is an OE-style cooling replacement for the 2013-2018 Acura RDX. Built to match factory specifications for core size, inlet and outlet dimensions, and material selection, it supports consistent engine temperature control in daily driving and demanding conditions.
Key Features
- Core height: 15.7480 in. for factory-style cooling coverage
- Core width: 30.2362 in. for proper radiator surface area
- Core thickness: 1.0236 in. for OE-matched cooling capacity
- Inlet diameter: 1.2795 in. and outlet diameter: 1.2913 in. for correct hose connection sizing
- Built to Denso OE standards for fitment, durability, and function
- Direct replacement radiator for Acura RDX cooling system service
Detailed Description
Denso part number 221-9558 is engineered as a radiator replacement for the Acura RDX, with dimensions and configuration details that align with OE requirements. Denso supplies radiators to vehicle manufacturers worldwide, and this unit reflects that OE-focused experience through controlled core dimensions, tank design, fin pitch, and material selection. For owners searching for a 2013-2018 Acura RDX radiator, this part number 221-9558 provides a direct-fit cooling solution that supports stable engine operation.
This radiator is a practical choice when replacing a leaking, clogged, or damaged cooling unit on the Acura RDX. It is also a fitment-based option for shoppers comparing Acura RDX radiator replacement parts, Denso radiator 221-9558, or OE-style cooling components for the same application.
This part cross-references Acura 19010R8AA51 for the same application.
What It Helps Address
- Coolant loss from a cracked or leaking radiator
- Overheating caused by restricted coolant flow
- Reduced cooling efficiency from internal corrosion or blockage
- Physical damage to the radiator core or tanks
- Temperature instability during stop-and-go or highway driving
Installation Notes and Tips
Fits 2013-2018 Acura RDX, N/A. Confirm hose diameter, mounting points, and overall core dimensions before installation. Flush the cooling system, inspect hoses and clamps, and replace degraded coolant as part of the repair. Verify proper bleed procedure after installation to remove trapped air and restore normal coolant circulation.
Quality Assurance
Denso states that its radiators are built to OE manufacturer standards and undergo durability and function testing before release. That OE-focused validation helps support reliable performance and fitment for Acura RDX cooling system service.
| Brand | Denso |
| Part Number | 221-9558 |
| Core Height | 15.7480 |
| Core Thickness | 1.0236 |
| Core Width | 30.2362 |
| Inlet Diameter | 1.2795 |
| Outlet Diameter | 1.2913 |
This part fits 6 vehicles. Search below:
| Year | Make | Model | Position | Notes |
|---|---|---|---|---|
| 2018 | Acura | RDX | N/A | |
| 2017 | Acura | RDX | N/A | |
| 2016 | Acura | RDX | N/A | |
| 2015 | Acura | RDX | N/A | |
| 2014 | Acura | RDX | N/A | |
| 2013 | Acura | RDX | N/A |
* Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
This part directly replaces or is cross-referenced with the following part numbers:
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.