Lexus RX ALA10

2.4L turbo four — replaces the 3.5L V6 in the 2023+ RX and NX 350. Adequate power but noticeably less refined than the V6 it replaces. Timing chain stretch is the long-term concern — inspection at 80,000 miles, replacement at 120,000 miles. EGR cooler cracks have been documented on early units. Fuel injection system issues can appear around 50,000-60,000 miles. Still a young engine with limited long-term data. The turbo-four in a luxury SUV feels like a cost reduction, not an improvement.

• !! Timing Chain Stretch from 130,000 km

  The T24A-FTS timing chain stretches over time despite Toyota marketing it as maintenance-free. Tensioners compensate initially but eventually the chain develops a subtle rattle. If unaddressed, the chain can jump or break, requiring engine replacement. Inspection recommended at 80,000 miles, replacement at 120,000 miles. Expected lifespan of the engine is 160,000-180,000 miles with proper maintenance.

  Symptoms: Subtle rattling noise on cold start, check engine light (timing codes), rough idle, reduced power
  2,000–5,000 $
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• !! EGR Cooler Cracking

  Early production T24A-FTS engines show cracking of the EGR cooler, allowing coolant to leak into the combustion chamber. Produces white smoke from exhaust and progressive coolant loss. The EGR valve itself can also clog around 100,000 miles. Early 2022-2023 production units appear most affected.

  Symptoms: White smoke from exhaust, coolant level dropping with no visible external leak, sweet smell from exhaust
  1,000–2,500 $
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• !! Fuel Injection System Complications from 90,000 km

  The D-4ST dual injection system is sensitive to fuel quality and purity. Injector fouling documented around 50,000-60,000 miles. The engine requires 91 octane premium fuel — using regular fuel can cause damage and may void warranty. Regular fuel filter changes recommended.

  Symptoms: Rough idle, hesitation under acceleration, check engine light, reduced fuel economy
  500–1,500 $
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