The 2020 Colorado is a mid-size truck with three powertrains showing distinctly different reliability profiles. The 3.6L V6 and 2.5L I4 are generally solid workhorses, but the 2.8L Duramax diesel has earned a reputation for catastrophic piston and crankshaft failures that can total the engine.
Symptoms: sudden loss of power under load, metallic knocking or rattling from crankcase, oil pressure warning light, metal shavings in oil during drain, coolant mixing with oil in severe cases
Fix: Complete engine rebuild or replacement required. Pistons crack or skirts disintegrate, crankshaft bearing surfaces score badly. Short block replacement is most common repair path, requiring 18-24 labor hours including removal, R&R of all accessories, fuel system bleeding, and ECM relearn. Some shops opt for reman long block. Extended warranty claims common but not always approved past 100k.
Estimated cost: $8,500-15,000
8-Speed Automatic Transmission Oil Cooler Leaks
Common · medium severity
Typical onset: 40,000-80,000 mi
Symptoms: transmission fluid puddling under vehicle, typically driver side, burnt transmission fluid smell, slipping or delayed shifts when fluid is low, check engine light with fluid temperature codes
Fix: Cooler lines corrode at crimp points or cooler itself develops pinhole leaks. Requires dropping the transmission skid plate, replacing cooler and lines as an assembly, flushing system, and refilling with Dexron HP ATF. 3-4 hours labor. Not a trans rebuild issue but will cause one if ignored.
Estimated cost: $600-1,200
Transmission Mount Failure (Rear Mount)
Common · low severity
Typical onset: 50,000-90,000 mi
Symptoms: clunk when shifting from park to drive or reverse, vibration felt through floor at idle in gear, excessive driveline movement visible during throttle tip-in, rattling over bumps from transmission tunnel area
Fix: Rubber isolator in rear transmission mount deteriorates and tears, especially on 4WD models with transfer case weight. Requires supporting transmission with jack, removing crossmember bolts, and replacing mount assembly. 1.5-2 hours. Often done during oil cooler repair if both are needed.
Estimated cost: $250-450
2.8L Duramax Diesel Fuel Filter Housing Leaks
Occasional · medium severity
Symptoms: diesel fuel smell in engine bay, hard starting or extended cranking, especially in cold weather, fuel weeping visible on top of engine near firewall, air in fuel system requiring multiple prime cycles
Fix: Filter housing develops leaks at seams or water-in-fuel sensor o-rings. Requires filter housing replacement, bleeding air from high-pressure fuel system, and priming. 2-3 hours labor. Not the serviceable filter element itself but the plastic housing that cracks. Aftermarket upgraded aluminum housings available.
Estimated cost: $400-800
3.6L V6 Timing Chain Stretch/Wear
Rare · high severity
Typical onset: 120,000-160,000 mi
Symptoms: rattling from front of engine on cold starts, check engine light with cam/crank correlation codes, reduced power or rough idle, metal flakes in oil filter during service
Fix: Primary timing chains stretch over time, causing variable valve timing issues and potential jump-time scenarios. Requires front-end disassembly, timing cover removal, replacement of both primary chains, guides, tensioners, and VVT components. 12-16 hours labor. Not common on 2020 models yet but watch for this as they age past 100k miles.
Estimated cost: $2,800-4,500
Diesel Exhaust Fluid (DEF) System Contamination
Occasional · medium severity
Symptoms: reduced engine power warning, check engine light with NOx sensor or SCR system codes, DEF system errors on instrument cluster, crystallized white deposits around DEF fill neck
Fix: Owners mistakenly add diesel fuel to DEF tank or use contaminated/expired DEF causing system failures. Requires complete DEF tank drain and flush, replacement of DEF pump, injector, lines, and potentially NOx sensors. Prevention is key—clearly label your DEF can. 4-6 hours for full system flush and component replacement.
Estimated cost: $1,500-3,500
Owner tips
Diesel owners: monitor oil consumption religiously and cut oil change intervals to 5k miles with quality 5W-40 diesel oil—may help prevent piston failures
Check transmission cooler lines during every oil change; catch leaks early before transmission damage occurs
Use only fresh DEF from sealed containers with recent production dates; old DEF crystallizes and kills sensors
V6 engines: look for timing chain rattle on cold starts as these trucks age—early detection prevents valve damage
Buy the V6 or 2.5L I4 gas models with confidence; avoid the 2.8L Duramax diesel unless you can verify bulletproof service history and budget for catastrophic engine failure risk.
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.
As an Amazon Associate, OLP earns from qualifying purchases — how we link. This never changes the specs we publish.
Every control module on the 2015-2026 Chevrolet Colorado — 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.
⚠️ 4G LTE from 2015+. Requires OnStar account and ESN programming. 2018+ SGW-locked.
Seat Control Module (SCM)0.8 hr R&Rrelearn only +0.2 hrwith power seats and memory function▸ programming details
📍 Under driver seat, mounted to seat frame
🔧 Self-calibration
⚠️ Controls seat position and memory. Self-calibration after replacement.
Headlamp Control Module (HCM)0.6 hr R&Rrelearn only +0.1 hrwith automatic headlamps or DRL▸ programming details
📍 Behind left headlamp assembly in engine compartment
🔧 Self-calibration
⚠️ Controls automatic headlamp operation and DRL. Basic models use BCM-integrated control.
Trailer Brake Control Module (TBCM)0.6 hr R&Rrelearn only +0.2 hrwith factory trailer brake controller▸ programming details
📍 Under instrument panel, left of steering column
🔧 Self-calibration via infotainment
⚠️ Integrated trailer brake controller. User calibration via touchscreen.
Rear Vision Camera Module (RVCM)0.5 hr R&Rrelearn only +0.1 hr▸ programming details
📍 Integrated with tailgate handle camera assembly
🔧 Self-calibration
⚠️ Standard equipment 2018+. Displays on infotainment screen. No programming typically required.
Tire Pressure Monitor Control Module (TPMS)relearn only +0.2 hr▸ programming details
📍 Integrated with BCM
🔧 TPMS relearn tool or GDS2/MDI
⚠️ Receives 315 MHz signals from wheel sensors. Sensor ID relearn required after tire service or sensor replacement.
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.
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 Chevrolet Colorado 2.8L I4 Duramax Diesel 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.