The 2020 CT4-V with the 2.7L turbo four is plagued by catastrophic low-speed pre-ignition (LSPI) issues causing engine failure, plus transmission cooler and mount problems that stem from the platform's aggressive tuning and inadequate cooling design.
Symptoms: Sudden knocking or rattling under moderate acceleration at low RPM, Check engine light with misfire codes, Metal shavings in oil during change, Complete loss of power or seized engine
Fix: Low-speed pre-ignition shatters pistons, bends rods, and damages bearings. Requires short block replacement or full engine rebuild. 18-25 labor hours depending on damage extent. GM has issued TSBs but no official recall as of this writing. Some warranty extensions exist.
Estimated cost: $8,000-15,000
Transmission Oil Cooler Failure
Common · medium severity
Typical onset: 40,000-80,000 mi
Symptoms: Transmission fluid leaking near front of vehicle, Transmission overheating warnings on dash, Harsh shifting when fluid is low, Pink or red fluid pooling under car
Fix: The external cooler lines corrode or the cooler itself cracks at mounting points. Requires cooler replacement, line flushing, and fluid fill. 3-4 labor hours. Check for cross-contamination if coolant mixes with trans fluid.
Estimated cost: $800-1,400
Transmission Mount Failure
Common · medium severity
Typical onset: 50,000-90,000 mi
Symptoms: Clunking when shifting from Park to Drive or Reverse, Excessive vibration at idle, Transmission appears to 'drop' during hard acceleration, Visible tearing or separation of rubber mount
Fix: The 10-speed trans mount tears from torque loads, especially on V models with higher boost. Requires lifting the transmission slightly for access. 2-3 labor hours. Upgrade to aftermarket polyurethane mount recommended for longevity.
Estimated cost: $400-700
High-Pressure Fuel Pump Failure
Occasional · high severity
Typical onset: 60,000-100,000 mi
Symptoms: Intermittent stalling, especially after cold start, Long crank time before engine fires, P0087 code (fuel rail pressure too low), Rough idle and hesitation under load
Fix: Direct-injection pump on these 2.7s fails from contaminated fuel or internal wear. Pump is engine-mounted, requires intake removal for access. 4-5 labor hours. Replace fuel filter simultaneously and check injectors for carbon buildup.
Estimated cost: $1,800-2,800
Turbocharger Wastegate Actuator Sticking
Occasional · medium severity
Typical onset: 70,000-110,000 mi
Symptoms: P0299 code (turbo underboost), Sluggish acceleration or limp mode, Whistling or fluttering noise from engine bay, Reduced power light illuminated
Fix: Wastegate actuator arm seizes from carbon buildup or vacuum actuator diaphragm fails. Often correctable with cleaning and lubrication if caught early; otherwise turbo replacement. 5-7 hours for turbo R&R on this platform due to tight packaging.
Estimated cost: $1,200-3,500
CUE Infotainment System Freezing/Rebooting
Common · low severity
Symptoms: Screen goes black or freezes randomly, Backup camera fails to display, Audio cuts out intermittently, System reboots during driving
Fix: Software glitch or failing main head unit board. Start with software update/reset (1 hour). If persistent, CUE module replacement required (2-3 hours for removal, programming). GM has issued multiple software patches.
Estimated cost: $200-2,000
Owner tips
Use only GM dexos1 Gen 2 oil and change every 5,000 miles max to reduce LSPI risk—ignore the 7,500-mile interval
Avoid lugging the engine below 2,000 RPM under heavy throttle; downshift instead to prevent pre-ignition events
Use Top Tier gasoline exclusively and add fuel system cleaner every 10,000 miles to keep injectors and intake valves clean
Inspect transmission cooler and lines annually for corrosion, especially in salt-belt states
Budget $1,000-1,500/year for repairs after warranty expires; these are high-maintenance performance vehicles
Skip it unless you find one with documented engine replacement under warranty and can budget for aggressive maintenance—the LSPI grenading risk makes this a 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.
Fitment notes: AGM battery required for start-stop system; located in trunk
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Every control module on the 2020-2026 Cadillac CT4-V — where it lives, replacement time, and what it takes to program a replacement. Modules marked dealer / factory tool won't work after a part swap alone — budget for programming.
⚠️ Power seat memory and heating/ventilation functions; two modules (driver/passenger)
Aftermarket tool coverage varies by software version and vehicle build — treat "aftermarket tool" rows as "usually possible" and verify against your tool maker's coverage list before promising a customer. Spot a wrong location or hour? Tell us — corrections ship fast here.
General Motors LLC (GM) is recalling certain 2019-2020 Cadillac CT6, 2020-2021 CT4, CT5, and 2020-2022 Chevrolet Camaro vehicles equipped with a 10-speed transmission. The transmission may become damaged internally and cause the wheels to lock-up.
Consequence: Wheel lock-up while driving increases the risk of a crash.
Remedy: Dealers will install transmission control module monitoring software, free of charge. Owner notification letters were mailed April 7, 2025. Owners may contact Cadillac customer service at 1-800-333-4223 or Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N242480630.
EXTERIOR LIGHTING:LIGHTING CONTROL MODULE:SOFTWARE · 22V903000
2022-12-08
General Motors, LLC (GM) is recalling certain 2020-2023 Cadillac CT4 and CT5; 2021-2023 Buick Envision; and 2022-2023 Cadillac Escalade and Escalade ESV, Chevrolet Silverado 1500, Suburban, Tahoe, GMC Sierra 1500, Yukon, and Yukon XL vehicles. The daytime running lights (DRLs) may not deactivate when the headlights are on. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 108, "Lamps, Reflective Devices, and Associated Equipment."
Consequence: DRLs that do not deactivate as intended may result in a glare, reducing visibility, and increasing the risk of a crash.
Remedy: The body control module software will be updated by a dealer, or through an over-the-air (OTA) update, free of charge. Owner notification letters were mailed January 23, 2023. Owners may contact GMC customer service at 1-888-988-7267, Chevrolet customer service at 1-800-222-1020, or Cadillac customer service at 1-800-458-8006. GM's number for this recall is N222386380. This recall expands previous recall number 22V-827.
AIR BAGS:SIDE/WINDOW:CURTAIN · 21V611000
2021-08-05
General Motors, LLC. (GM) is recalling certain 2020-2022 Cadillac CT4 and CT5 vehicles. The roof rail side-curtain air bags may not have been installed correctly, which could result in an improper air bag deployment during a crash.
Consequence: Air bags that do not deploy properly can increase the risk of injury in a crash.
Remedy: Dealers will inspect both left and right-side roof rail air bags and reinstall the air bags, as necessary, free of charge. Owner notification letters were mailed on August 30, 2021. Owners may contact Cadillac customer service at 1-800-458-8006. GM's number for this recall is N212342780.
SERVICE BRAKES · 20V588000
2020-09-24
General Motors LLC (GM) is recalling certain 2020 Chevrolet Corvette and Cadillac CT4, CT5 and XT4, 2021 Chevrolet Trailblazer, and 2020-2021 Buick Encore GX vehicles. Sensor connection contamination in the electronic brake boost system may cause an interruption of communication between the sensor and the brake boost system.
Consequence: If communication with the sensor is interrupted, the electronic brake boost assist could be lost. Extra pedal force will be required to slow and stop the vehicle, increasing the risk of a crash.
Remedy: GM will notify owners, and dealers will replace the electronic brake boost module, free of charge. The recall began December 9, 2020. Owners may contact Chevrolet customer service at 1-800-630-2438, Cadillac customer service at 1-800-333-4223, or Buick customer service at 1-800-521-7300. GM's number for this recall is A202307260.
Size-standard part numbers — verify your connector type before buying. Rear blades are model-specific; check the package's vehicle list.
Fuel economy figures are EPA data via fueleconomy.gov (median across matching trims). Performance figures are compiled estimates for the 2020 Cadillac CT4-V 2.7L Turbo I4 and can vary by trim.
🔧 Database maintained under the daily editorial review of Chris Hackleman · Master Technician · 20+ years and Jeff Moore · Master Lexus & Toyota Mechanic · 20+ years.