2018-2026 Jeep Wrangler, Gladiator JL JT 4 Row 5MM Fin, Extruded Tube Aluminum Radiator

High Performance Replacement Radiator

OVERVIEW

The stock Jeep Wrangler JL JT radiator was built to a cost target, not a performance standard. Under sustained off-road use, towing, or high-ambient temperatures, it shows — coolant temps climb, and the thin-walled tubes that the OEM core relies on are the first thing to give.

The Fluidyne JL JT High Performance Replacement Radiator is a direct swap for the factory unit on both the 3.6L Pentastar and 2.0L, built with extruded aluminum tubes and a 5mm high-density fin pitch. The result is a radiator that fits exactly like stock and outperforms it in every condition that matters.

KEY DIFFERENTIATORS

Extruded Aluminum Tubes

Formed as a single continuous extrusion — no seams, no joints along the tube wall. Conventional tube construction creates stress points at every joint; Fluidyne’s extruded tubes eliminate that failure mode entirely.

5mm Fin Pitch

Tighter fin spacing increases surface area in contact with airflow, accelerating heat transfer per square inch of core. More cooling capacity within the same envelope as the factory radiator.

True Direct Fit

Designed to the OEM envelope — accommodates the stock JL JT radiator fan, A/C condenser, and transmission cooler with no fabrication, no adapter brackets, and no modifications.

Full Aluminum Construction

Tanks, core, and extruded tubes are all aluminum — minimizing corrosion potential and reducing weight compared to the factory unit’s mixed-material construction.

WHY TUBE CONSTRUCTION MATTERS

Most radiator failures aren’t caused by the fins or tanks — they’re caused by the tubes. Conventional tube construction creates stress points along every joint. Under the thermal cycling of regular off-road use — heat soaking on the trail, rapid cool-down, repeated over and over — those stress points are where cracks initiate and leaks develop.

Fluidyne’s extruded tubes have no longitudinal seam. The tube is the extrusion. There is no joint to fail.

FEATURES

• Extruded aluminum tubes — seamless wall construction, no joints along tube length
• 5mm fin pitch for maximized core surface area and heat transfer
• Increased core volume and coolant capacity over stock JL JT  radiator
• Dual-pass coolant flow — extends dwell time in the core for more effective heat extraction
• TIG-welded tank-to-core interface
• Compatible with stock JK fan, A/C condenser, and transmission cooler
• Fits both 3.6L Pentastar V6 and 2.0L applications
• Includes high-pressure radiator cap and magnetic drain plug
• Direct fit — no modification required for 2018+ JL JT

Note: This radiator is a performance replacement for the stock JK cooling system and is compatible with both the 3.6L Pentastar V6 and the 2.0L. It is not intended for HEMI, LS or other engine swap applications — see part no. RJP.JKHEMI for HEMI conversion fitment and RJP.JKLS for LS Swaps.