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CSF 3688 Drive Motor Inverter Cooler
Drive Motor Inverter Cooler for Lexus RX450h
CSF 3688 is a direct-fit drive motor inverter cooler built for 2010-2015 Lexus RX450h applications. It uses an OE-style plastic tank and aluminum core layout, with an upgraded B-tube design for improved cooling efficiency and durability.
For Lexus RX450h owners searching for a replacement inverter cooler, CSF 3688 provides the correct cross-flow configuration and factory-style dimensions for a clean fit. The part number 3688 is also referenced in OE-style cooling replacement searches for this vehicle platform.
Key Features
- OE-style plastic tank and aluminum core construction
- 1-row, cross-flow design
- Upgraded higher-performance B-tube core design
- Top hose fitting: 11/16 right
- Bottom hose fitting: 11/16 left
- Core size: 26 5/16 in. length x 3 1/4 in. width x 7/8 in. thickness
- Built for 2010-2015 Lexus RX450h fitment
- CSF part number 3688
Detailed Description
CSF 3688 is engineered as a replacement drive motor inverter cooler for the 2010-2015 Lexus RX450h. The unit combines a plastic tank design with an aluminum core to match OE-style packaging while using a stronger B-tube core structure for improved heat transfer performance. CSF manufactures a wide range of cooling components and validates designs through laboratory wind-tunnel testing to confirm cooling performance.
This cooler is a practical choice for Lexus RX450h cooling system service when the original inverter cooler is leaking, restricted, or no longer maintaining proper thermal control. The cross-flow layout, inlet and outlet sizing, and overall core dimensions are specified to support accurate replacement selection. Part number 3688 is also commonly searched alongside Lexus RX450h inverter cooler replacement needs.
This part cross-references Bosch 13355 for the same application.
What It Helps Address
- Inverter cooling loss from a leaking or damaged cooler
- Restricted coolant flow through a clogged core
- Overheating concerns in hybrid drive motor inverter systems
- Fitment issues caused by using the wrong core style or hose orientation
- Replacement needs for aging OE-style plastic tank coolers
Installation Notes and Tips
Verify hose orientation, inlet and outlet dimensions, and mounting layout before installation. This cooler is a cross-flow design with 11/16 in. right top hose fitting and 11/16 in. left bottom hose fitting, so matching the original configuration is important for proper routing. Radiator cap is not supplied.
For best results, inspect related coolant hoses and connections during replacement and confirm the vehicle is a 2010-2015 Lexus RX450h. Use the listed core dimensions and OE-style tank construction to compare against the removed unit before installation.
Quality Assurance
CSF builds cooling products to high-performance standards and manufactures a broad catalog of radiator and cooler applications for leading vehicle brands. The company states its factories are ISO/TSO certified and its designs are validated through laboratory testing for cooling performance.
| Brand | CSF |
| Part Number | 3688 |
| Position | 1 Row Plastic Tank Aluminum Core |
| Core Material | Aluminum |
| Tank Material | Plastic |
| Bottom Hose Fitting (in) | 11/16 left |
| Box Height (in) | 4 1/8 |
| Box Length (in) | 31 5/8 |
| Box Weight (lbs) | 4 |
| Box Width (in) | 7 13/16 |
| Core Length (in) | 26 5/16 |
| Core Thickness (in) | 7/8 |
| Core Width (in) | 3 1/4 |
| Cross-flow/ Down-flow | Cross flow |
| Hazardous Material | No |
| Inlet Length (in) | 3 5/8 |
| Inlet Width (in) | 1 1/4 |
| No. Of Rows | 1 |
| Outlet Length (in) | 3 5/8 |
| Outlet Width (in) | 1 1/4 |
| Radiator Cap Supplied | No |
| Tech Note | O.e.m. style plastic tanks & aluminum core. upgraded with higher |
| Top Hose Fitting (in) | 11/16 right |
This part fits 6 vehicles. Search below:
| Year | Make | Model | Liters | Cylinders | Fuel Type | Position | Notes |
|---|---|---|---|---|---|---|---|
| 2015 | Lexus | RX450h | 3.5L | V6 | FULL HYBRID EV-GAS (FHEV) | N/A | Upgraded with Higher Performance & Stronger B-Tube Design; 1 Row Plastic Tank Aluminum Core |
| 2014 | Lexus | RX450h | 3.5L | V6 | FULL HYBRID EV-GAS (FHEV) | N/A | Upgraded with Higher Performance & Stronger B-Tube Design; 1 Row Plastic Tank Aluminum Core |
| 2013 | Lexus | RX450h | 3.5L | V6 | FULL HYBRID EV-GAS (FHEV) | N/A | Upgraded with Higher Performance & Stronger B-Tube Design; 1 Row Plastic Tank Aluminum Core |
| 2012 | Lexus | RX450h | 3.5L | V6 | FULL HYBRID EV-GAS (FHEV) | N/A | Upgraded with Higher Performance & Stronger B-Tube Design; 1 Row Plastic Tank Aluminum Core |
| 2011 | Lexus | RX450h | 3.5L | V6 | FULL HYBRID EV-GAS (FHEV) | N/A | Upgraded with Higher Performance & Stronger B-Tube Design; 1 Row Plastic Tank Aluminum Core |
| 2010 | Lexus | RX450h | 3.5L | V6 | FULL HYBRID EV-GAS (FHEV) | N/A | Upgraded with Higher Performance & Stronger B-Tube Design; 1 Row Plastic Tank Aluminum Core |
* 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.