The 2021 Range Rover Sport with the 3.0L supercharged V6 is a luxury SUV plagued by catastrophic engine failures stemming from defective piston rings and cooling system issues, often requiring complete rebuilds well before 100,000 miles. While newer than problem years, shares DNA with known failure-prone AJ-V6 architecture.
Catastrophic Engine Failure - Piston Ring / Bearing Destruction
Occasional · high severityTypical onset: 40,000-80,000 mi
Symptoms: Excessive oil consumption (quart every 500-1,000 miles), White or blue smoke from exhaust on startup, Metallic knocking or ticking from engine block, Sudden loss of power followed by seizure, Check engine light with misfire codes or low oil pressure warning
Fix: Complete engine rebuild or short block replacement required. Involves removing entire engine, machining or replacing block, new pistons, rings, bearings, gaskets, timing components. 35-50 labor hours depending on shop efficiency and damage extent. Some engines seize suddenly requiring core replacement.
Estimated cost: $15,000-28,000
Transmission Oil Cooler Failure with Contamination
Common · high severityTypical onset: 50,000-90,000 mi
Symptoms: Transmission slipping or harsh shifting, Milky or strawberry-colored transmission fluid, Overheating warnings on dashboard, Loss of drive or limp mode engagement, Coolant in transmission pan or transmission fluid in coolant reservoir
Fix: Replace transmission oil cooler, flush both cooling system and transmission multiple times, replace transmission fluid and filter. If contamination severe, transmission rebuild required. Cooler replacement alone is 8-12 hours; with transmission damage add 20-30 hours.
Estimated cost: $2,800-4,500 (cooler only); $8,000-14,000 (with transmission rebuild)
Supercharger Coupler and Bearing Failure
Occasional · medium severityTypical onset: 60,000-100,000 mi
Symptoms: High-pitched whining or grinding noise from engine bay on acceleration, Loss of boost pressure and reduced power output, Check engine light with boost control codes, Rubber debris in intake tract or engine bay, Rattling noise at idle that worsens under load
Fix: Remove supercharger, replace coupler and front bearing assembly, inspect rotor pack for damage, reseal unit. Requires special pulley tools and calibration. 12-16 labor hours including removal and reinstallation.
Estimated cost: $3,200-5,500
Timing Chain Guide and Tensioner Wear
Occasional · high severityTypical onset: 70,000-110,000 mi
Symptoms: Rattling from front of engine on cold starts (first 5-10 seconds), Check engine light with cam/crank correlation codes, Rough idle or misfires, Metal shavings in oil during changes, Engine runs rough or won't start if chain jumps timing
Fix: Replace timing chains, guides, tensioners, and variable valve timing components on both banks. Engine front disassembly required. Critical preventive item if noise present. 18-24 labor hours.
Estimated cost: $4,500-7,200
Electronic Parking Brake Module Failure
Occasional · medium severitySymptoms: Parking brake malfunction warning on dash, Parking brake won't engage or release, Grinding or clicking from rear calipers, Vehicle rolls when parked on incline, EPB fault message requiring manual release procedure
Fix: Replace electronic parking brake module and/or rear brake calipers with integrated actuators. Requires dealer-level scan tool for calibration and bleeding procedure. 3-5 hours per side including programming.
Estimated cost: $1,800-3,200
Transfer Case Oil Leak and Bearing Wear
Common · medium severityTypical onset: 50,000-90,000 mi
Symptoms: Oil puddle under center of vehicle, Whining or grinding noise from center driveline, Clunking when shifting between drive ranges, HDC or terrain response faults on dashboard, Binding feeling during tight turns
Fix: Replace transfer case seals, check fluid level and condition. If bearings damaged, requires transfer case rebuild or replacement unit. Seal replacement is 4-6 hours; full rebuild/replace is 10-14 hours with driveshaft removal.
Estimated cost: $1,200-2,000 (seals); $4,500-7,000 (rebuild/replacement)
Coolant Crossover Pipe and Water Pump Leaks
Common · medium severityTypical onset: 60,000-100,000 mi
Symptoms: Coolant leak from valley between cylinder banks, Sweet smell in cabin or under hood, Overheating warning or temperature gauge climbing, Low coolant warning light frequent top-ups needed, White residue on engine valley cover or supercharger
Fix: Remove supercharger and intake manifold to access crossover pipes in valley, replace pipes, hoses, water pump, and thermostat as assembly. Critical to prevent engine overheat damage. 10-14 labor hours.
Estimated cost: $2,800-4,200
Hard pass unless under factory warranty or you have $20K+ in reserve for inevitable engine rebuild — the catastrophic failure rate and repair costs make this a financial gamble even at low mileage.
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.