The JL Jeep Wrangler already has a tightly packed engine compartment but for the 2022-2024 Wrangler Rubicon 392 the 6.4-liter V-8 engine is an especially unique situation in every sense of the word when it comes to packaging, specifications and its engine bay components.
The 6.4-liter “Hemi” V8 known as the 392 by its cubic inch count is rated in the Wrangler at 470 horsepower and 470 pound-feet of torque. It comes mated to an 8-speed automatic transmission and full-time four-wheel drive. In the Wrangler Rubicon we have here that delivers a 0-60 mph time of about 4.5 seconds.
The 6.4-liter V-8 uses a cast iron cylinder block, aluminum heads, active composite plastic intake manifold, variable camshaft timing, and two spark plugs per cylinder and features a more traditional port fuel injection instead of direct injectors. It does however have cylinder deactivation which can allow it to run on four cylinders to save fuel when the extra power is not needed.
One of the most unique features of this installation is the ornate and complex Hydro-Guide air intake system that allows the Wrangler Rubicon 392 to almost swim through water without inhaling any of it. The air induction hood has a tri-level ducting system with a series of drains, including a one-way drain in the air box that can separates up to 15 gallons of water per minute.
That leads to the intake airflow which after coming through all of that ducting which is sealed to its airbox, then travels through the high-flow filter and then through a tube to a large throat throttle body and into its active intake manifold. From there its off and into the cylinders.
The spark plug coil packs can mostly be seen at each side, though accessing them does require some effort. Most of the fuel injection system is hidden below the easily removable decorative plastic covers at each side.
Once combustion is complete it heads out of the aluminum heads at the lower banks and into a high-flow exhaust system featuring an active dual-mode system that allows for variable sound and loudness. The system engages automatically, opening valves in the exhaust system, under higher engine loads to reduce exhaust back pressure. The driver can also activate the system with the press of a button.
Servicing the Wrangler Rubicon 392 however is as average as any other vehicle. Most of the fluids and components are within easy reach. First and most notable, this Wrangler still features hydraulic power steering so there’s a fluid reservoir at the front passenger side of the engine to keep track of. Rare today.
The 12V battery is found near the passenger side firewall, ahead of it the main ECU and ahead of that the main fuse box. The engine oil dipstick is found at the top of the valve cover at the driver side and the oil filler cap can also be found nearby. The engine oil filter however must be accessed from below.
On the driver side near the firewall you will find grouped together the main engine coolant reservoir, the brake fluid reservoir and to its right the windshield washer fluid tank. Notably this Wrangler still uses a conventional brake fluid master cylinder and brake booster though the modern ABS control unit can be found ahead.
Lastly the main engine electric cooling fan can be seen looking forward toward the rear of the radiator. Always be cautious as it can start running at any time even if the engine has been turned off.
