The 2024 RX 350 uses Toyota's new T24A-FTS 2.4L turbo four-cylinder with an 8-speed automatic. Too new for widespread pattern failures, but early adopters are seeing turbo oiling issues and concerning transmission behavior that echo problems from the corporate RAV4/Highlander platform siblings.
Turbocharger Oil Starvation / Carbon Buildup
Occasional · high severityTypical onset: 15,000-40,000 mi
Symptoms: Check engine light with P0299 (turbo underboost), Blue smoke on cold start, Loss of power under acceleration, Excessive oil consumption (1 qt per 1,000-1,500 mi)
Fix: Early T24A engines show inadequate turbo oiling at idle and carbon fouling in oil return lines. Fix requires turbo replacement and updated oil feed lines if TSB applies. 6-8 hours labor. Some dealers doing goodwill warranty extensions.
Estimated cost: $2,800-4,200
8-Speed Transmission Shudder and Harsh Shifts
Common · medium severityTypical onset: 5,000-25,000 mi
Symptoms: Vibration during light acceleration 25-45 mph, Hard 2-3 or 3-4 upshifts when cold, Hesitation when merging or passing, Transmission fluid smells burnt prematurely
Fix: Direct Shift-8AT has torque converter lockup calibration issues. Dealers perform software flash first (1 hour), but recurring cases need transmission fluid exchange with Toyota WS fluid and sometimes torque converter replacement (8-10 hours). Transmission oil cooler issues compound this.
Estimated cost: $350-3,500
Fuel Injector Coking and Misfires
Occasional · medium severityTypical onset: 20,000-50,000 mi
Symptoms: Intermittent misfire codes (P030X), Rough idle when engine is hot, Reduced fuel economy (3-5 mpg drop), Hesitation off idle
Fix: Direct injection only (no port injection) on T24A makes it sensitive to fuel quality. Carbon builds on injector tips. Requires injector cleaning or replacement. 3-4 hours labor for all four injectors plus rail work.
Estimated cost: $800-1,600
PCV System Clogging and Oil Leaks
Occasional · medium severityTypical onset: 30,000-60,000 mi
Symptoms: Oil weeping from valve cover or turbo seals, Positive crankcase pressure (dipstick pops out), Rough idle with P0171/P0174 lean codes, Oil in intake tract
Fix: Turbocharged DI engines generate more blowby. Integrated PCV valve in valve cover clogs with sludge if using extended oil change intervals. Requires valve cover replacement (PCV non-serviceable). 2-3 hours labor.
Estimated cost: $600-950
Transmission Mount Failure
Common · low severityTypical onset: 25,000-50,000 mi
Symptoms: Clunk when shifting from Park to Drive or Reverse, Vibration through steering wheel at idle in Drive, Excessive engine movement visible from driver seat
Fix: The hydraulic transmission mount is undersized for the turbo four's torque characteristics. Mount tears internally. Straightforward replacement but requires supporting powertrain. 1.5-2 hours labor.
Estimated cost: $350-550
Engine Knock from Low-Speed Pre-Ignition (LSPI)
Rare · high severitySymptoms: Audible metallic knock under hard acceleration below 2,500 RPM, Check engine light with knock sensor codes, In severe cases: catastrophic engine failure (rod through block)
Fix: Turbocharged DI engines can experience pre-ignition events that detonate fuel-oil droplets. Catastrophic failures have occurred under 10,000 miles. Warranty replacement requires documenting knock. Engine rebuild or short block: 18-24 hours labor. Use only manufacturer-spec oils.
Estimated cost: $8,000-14,000
Skip the first model year—wait for 2026+ after Toyota works out the T24A's teething issues; proven V6 RX models are far safer used buys.
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.