The 2004 Acura RL with its J35A4 V6 is a capable luxury sedan, but it's plagued by a catastrophic transmission failure issue and serious engine oil consumption problems that can destroy the motor if ignored. These aren't minor annoyances—they're platform-defining failures that make high-mileage examples a gamble.
Automatic Transmission Failure (3rd/4th Gear Clutch Pack)
Common · high severityTypical onset: 80,000-140,000 mi
Symptoms: Harsh or delayed 2nd-to-3rd gear shifts, especially when cold, Slipping or flaring on 3rd-4th upshifts under moderate throttle, Check engine light with P0730, P0740, or P1738 codes, Burnt transmission fluid smell, dark/metallic fluid on dipstick
Fix: The 5-speed auto has weak 3rd gear clutch packs and inadequate cooling. Rebuild requires full teardown, new clutches, bands, seals, and torque converter. 12-16 hours labor. Some shops won't touch these—expect a reman unit instead.
Estimated cost: $3,500-5,500
Severe Engine Oil Consumption (Piston Ring Failure)
Common · high severityTypical onset: 60,000-120,000 mi
Symptoms: Burning through 1+ quart of oil every 500-1,000 miles, Blue smoke on startup or acceleration after engine is warm, Fouled spark plugs, misfires (P0300-P0306 codes), No external leaks—oil literally disappearing into combustion chambers
Fix: Honda's J35A4 has design issues with ring sealing and oil control. Fix requires engine-out teardown, hone cylinders, new piston rings, valve seals, gaskets. 20-28 hours labor. Some techs recommend short-block replacement if cylinder wear is severe.
Estimated cost: $4,000-7,000
Transmission Oil Cooler Line Leaks
Common · medium severityTypical onset: 70,000-110,000 mi
Symptoms: Transmission fluid puddles under front of vehicle, Fluid dripping from area near radiator or A/C condenser, Low transmission fluid level causing delayed engagement or slipping, Visible corrosion or green crusty buildup on cooler lines
Fix: The steel lines rust through where they connect to the radiator or run along subframe. Replace both feed and return lines as a pair. 2-3 hours labor. Flush transmission and refill with Honda DW-1 ATF only.
Estimated cost: $400-700
Rear Transmission Mount Collapse
Common · medium severityTypical onset: 80,000-130,000 mi
Symptoms: Clunking or banging when shifting from Park to Drive/Reverse, Excessive engine/trans movement visible from engine bay during acceleration, Vibration at idle that worsens with A/C or electrical load, Driveline shudder during moderate acceleration from a stop
Fix: The hydraulic rear mount degrades and loses damping. Replacement requires supporting the transmission and removing cross-member bolts. 1.5-2 hours labor. Use OEM Honda part—aftermarket mounts fail quickly.
Estimated cost: $350-550
Fuel Filter Clogging (In-Tank Sock Filter)
Occasional · medium severityTypical onset: 100,000-150,000 mi
Symptoms: Hard starting, especially when fuel tank is below 1/4 full, Sputtering or loss of power under hard acceleration, Intermittent stalling at idle after driving in hot weather, Fuel pump noise (whining) more audible than normal
Fix: Honda integrated the filter into the fuel pump assembly. No serviceable inline filter exists. Must drop the fuel tank and replace entire pump/sender unit. 2.5-3.5 hours labor.
Estimated cost: $600-900
VTM-4 (AWD) Rear Differential Fluid Leak
Occasional · low severityTypical onset: 90,000-140,000 mi
Symptoms: Gear oil seeping from rear differential pinion seal or axle seals, Whining or growling noise from rear during turns if fluid is low, VTM-4 warning light if differential overheats from low fluid, Visible wetness on rear diff housing or inner CV boots
Fix: The AWD system's electromagnetic clutch pack overheats if fluid is low. Replace leaking seals and refill with Honda Dual Pump II fluid—nothing else. 1.5-2.5 hours depending on seal location.
Estimated cost: $300-600
Only buy one under 80,000 miles with documented transmission services and no oil consumption—otherwise you're inheriting someone else's ticking time bomb.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.