The 2021 CT5 is relatively new to the market, but early adopters are reporting concerning powertrain issues—particularly catastrophic 2.0T failures requiring engine rebuilds at surprisingly low mileage. The 3.0TT has been more reliable, though transmission cooler and mount issues affect both variants.
Symptoms: Sudden metal-on-metal knocking noise, Check engine light with misfire codes and low oil pressure warnings, Excessive oil consumption (1 qt per 1,000 mi or worse) before failure, Metal shavings in oil during routine changes
Fix: Complete engine rebuild or short block replacement required. We're seeing cracked pistons, spun bearings, and scored cylinder walls. 18-24 labor hours for short block swap, additional time if full teardown needed for diagnosis. GM has extended warranty coverage on some VINs but not all.
Estimated cost: $8,000-15,000
Transmission Oil Cooler Line Leaks
Common · medium severity
Typical onset: 40,000-80,000 mi
Symptoms: Transmission fluid puddles under vehicle, typically passenger side, Low transmission fluid warning on dashboard, Harsh shifting or slipping if fluid level drops significantly, Pink or red fluid visible on cooler lines near radiator
Fix: Cooler line connections corrode or crack where they meet the radiator. Replace both lines and flush transmission fluid. 2.5-3.5 hours labor. Not a recall yet but should be—seeing it across 10-speed equipped GM vehicles.
Estimated cost: $600-1,100
Transmission Mount Failure (Rear Mount)
Common · low severity
Typical onset: 50,000-90,000 mi
Symptoms: Clunking when shifting from Park to Drive or Reverse, Vibration felt through center console at idle, Excessive drivetrain movement visible under acceleration, Rattling over bumps from transmission area
Fix: Rear transmission mount tears or separates from bracket. Common on both engines but especially 3.0TT due to torque. Replace mount and inspect neighboring mounts. 1.5-2 hours labor.
Estimated cost: $350-550
Fuel Filter Clogging (High-Pressure Filter)
Occasional · medium severity
Typical onset: 60,000-100,000 mi
Symptoms: Hard starting, especially when engine is warm, Loss of power under acceleration or at highway speeds, Rough idle and intermittent stalling, P0087 code (fuel rail pressure too low)
Fix: High-pressure fuel filter in tank becomes restricted with debris. Requires fuel tank drop and filter replacement. Not a scheduled maintenance item in manual but should be. 3-4 hours labor including tank removal.
Symptoms: Airbag warning light illuminated on dash, No physical symptoms but safety system disabled, Recall notice received for side curtain airbag inflator
Fix: GM recall 21V-841 addresses side curtain airbag inflators that may rupture during deployment. Dealer replaces inflator assemblies. 2-3 hours at dealer, covered under recall. Check if your VIN is affected before purchase.
Estimated cost: $0 (recall)
Lighting Control Module Software Glitch
Occasional · low severity
Symptoms: Headlights or tail lights fail to turn on or off properly, Automatic high beams malfunction, Lighting warning messages on dash, Exterior lights flicker or remain on after vehicle is off
Fix: Software issue in body control module. Dealer reflash usually resolves it—covered under recall 22V-897. If module hardware failed, replacement runs 1.5 hours labor plus $400-600 for part.
Estimated cost: $0-800
Owner tips
If buying a 2.0T, get a pre-purchase oil analysis and check for metal particles—walk away if present
Change transmission fluid at 50k intervals despite GM's 'lifetime fill' claim, especially if you see cooler line seepage
Verify all recall work completed before purchase—especially airbag and lighting control module updates
Consider extended warranty if buying used 2.0T—the engine rebuild risk is real and expensive
Buy the 3.0TT if you want this platform; avoid the 2.0T unless you have comprehensive warranty coverage through 100k miles.
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; located in trunk; part of premium electrical system for twin-turbo application
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Every control module on the 2020-2026 Cadillac CT5 — 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.
⚠️ Memory seat calibration; aftermarket tools generally capable
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.
AIR BAGS:SRS MALFUNCTION WARNING LAMP/LIGHT · 21V421000
2021-06-10
General Motors, LLC (GM) is recalling certain 2021 Buick Envision, Cadillac CT4, CT5, Escalade, Escalade ESV, Chevrolet Tahoe, Corvette, Suburban, GMC Yukon, Yukon XL vehicles. The communications gateway module incorrectly processes a loss of communication with the sensing diagnostic module (SDM), causing the air bag malfunction indicator light to inconsistently illuminate.
Consequence: The air bag malfunction indicator light may fail to warn the driver of a problem with the air bag, increasing the risk of injury.
Remedy: The communications gateway module software will be updated by a dealer, or through an over-the-air (OTA) update, free of charge. Owner notification letters were mailed on July 1, 2021. Owners may contact Buick customer service at 1-800-521-7300, Cadillac customer service at 1-800-458-8006, Chevrolet customer service at 1-800-222-1020, or GMC customer service at 1-800-462-8782. GM's number for this recall is N212338110.
Performance
Horsepower
335hp
Torque
405lb-ft
0–60 mph
4.6sec
Quarter mile
13.1sec
Top speed
155mph
Fuel economy (EPA)
City
19mpg
Highway
28mpg
Combined
22mpg
Fuel
Premium Gasoline
Capability & size
Curb weight
4,048lb
EPA class
Midsize Cars
Wiper blades
Sedan body style, no rear wiper. Unchanged from 2020.
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 2021 Cadillac CT5 3.0L Twin-Turbo V6 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.