The 2020 Blazer sits on GM's C1 platform (shared with XT5/Acadia) and represents a high-stakes reboot. While generally competent, the 2.0T and 3.6L engines carry carryover issues from previous applications, and the 9-speed transmission proves troublesome in stop-and-go duty.
Symptoms: Pronounced shudder during light acceleration or coasting 25-45 mph, Harsh downshifts when slowing, Hesitation or delayed engagement from stop, Transmission learns bad shift patterns over time
Fix: TSB reprograms and fluid changes help temporarily. Persistent cases need torque converter replacement (6-8 hours labor). Some units require complete transmission overhaul or replacement at higher mileage. Transmission oil cooler often fails separately, contaminating fluid.
Estimated cost: $800-1,200 for converter; $3,500-5,500 for reman transmission
2.0L Turbo Piston Ring Failure & Oil Consumption
Occasional · high severity
Typical onset: 60,000-100,000 mi
Symptoms: Excessive oil consumption (1 qt per 1,000 mi or worse), Blue smoke on cold start or hard acceleration, Spark plug fouling, misfires on cylinders 2 and 3 especially, Loss of power under boost
Fix: Piston ring lands crack due to carbon buildup and thermal stress. Requires engine teardown: pistons, rings, honing, head gasket set (18-24 hours). Some shops opt for used/reman short block swap instead. This is a known GM 2.0T LTG weakness carried over from ATS/Malibu generations.
Estimated cost: $4,500-7,000 for in-frame rebuild; $6,000-8,500 for short block
3.6L V6 Timing Chain Stretch & Guide Wear
Occasional · high severity
Typical onset: 80,000-120,000 mi
Symptoms: Cold-start rattle from front of engine lasting 3-5 seconds, Check engine light with P0016/P0017 cam-crank correlation codes, Rough idle, hesitation on acceleration, Metallic rattling under load
Fix: GM's 3.6L HFV6 suffers premature timing chain stretch. Requires front cover removal, all chains, guides, tensioners, cam phasers, and water pump while in there (12-16 hours labor). Delayed repair risks jumped timing and valve-piston contact.
Estimated cost: $2,800-4,200
Transmission Mount Failure (AWD Models)
Common · low severity
Typical onset: 40,000-80,000 mi
Symptoms: Clunk when shifting from Park to Drive or Reverse, Vibration at idle in gear, Excessive driveline movement felt through cabin
Fix: Rear transmission mount (on PTU for AWD) tears or separates. Simple replacement, but requires supporting transmission (2-3 hours). Some techs replace all three engine/trans mounts at once for labor efficiency.
Estimated cost: $350-600 for rear mount; $800-1,200 for all three
Fuel Pump / Low Pressure Fuel System Concerns
Occasional · medium severity
Symptoms: Hard starting or extended crank after sitting, Stumble or hesitation on acceleration, Intermittent stalling, especially when fuel tank below 1/4, P0087 low fuel pressure code
Fix: In-tank fuel pump module fails, sometimes just the low-pressure pump side. Requires dropping tank (3-4 hours). Not unique to Blazer but common across GM C1 platform vehicles with direct injection. Use OE or quality aftermarket; cheap pumps fail fast.
Estimated cost: $700-1,100
Infotainment System / Software Glitches
Common · low severity
Symptoms: 8-inch touchscreen freezes or reboots randomly, Apple CarPlay or Android Auto disconnects, Backup camera delayed or black screen, Climate controls unresponsive via touchscreen
Fix: Software-related; GM has issued multiple updates. Dealer flash takes 0.5-1 hour but often returns. Hard reset (pull fuse 46 for 2 minutes) sometimes helps. Persistent cases may need display/radio module replacement, but warranty usually covers early failures.
Estimated cost: $100-200 for software flash; $1,200-1,800 for module replacement
Owner tips
If buying the 2.0T, verify oil consumption history and check spark plugs for fouling before purchase
On 3.6L models, listen carefully for cold-start rattle and budget for timing chains if over 80k miles
9-speed trans: change fluid at 50k mi regardless of 'lifetime fill' marketing; use Honda/Acura ATF-DW1
AWD Blazers: inspect PTU fluid level at 30k intervals; these run hot and leak often
Keep fuel tank above 1/4 to avoid stressing in-tank pump; use Top Tier fuel to minimize carbon on 2.0T
Good lease, risky used buy after 60k miles — budget $2-3k cushion for 2.0T or 3.6L engine work and expect transmission issues on high-mileage examples.
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: H6 group may also fit; AGM recommended for start-stop systems
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Control Modules — 2020 Chevrolet Blazer
Every control module on the 2019-2024 Chevrolet Blazer — 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.
⚠️ Controls automatic headlamps, DRL, high beam assist. Configuration programming recommended but not always required.
Tire Pressure Monitor Control Module (TPMS)relearn only +0.2 hr▸ programming details
📍 integrated in BCM
🔧 TPMS relearn tool or GDS2
⚠️ TPMS receiver integrated in BCM. Sensor IDs must be relearned after tire rotation or sensor replacement. 315 MHz sensors.
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 2020 Buick Enclave, Cadillac XT4, XT5, Escalade, Escalade ESV, Chevrolet Suburban, Tahoe, Traverse, GMC Yukon, Yukon XL, 2018-2021 Chevrolet Express, GMC Savana, 2019-2020 Chevrolet Blazer, Silverado 1500, GMC Acadia, Sierra 1500, and certain Continental tires sold to the aftermarket for various model year 2018-2021 vehicles. The affected tires were cured for too long during production.
Consequence: Over cured tires may develop a break in the sidewall resulting in sudden air loss or a belt edge separation which could lead to a tread/belt loss. Either condition can cause a loss of vehicle control, increasing the risk of a crash.
Remedy: GM will notify owners, and dealers will inspect the tires, replacing them as necessary, free of charge. The recall began March 22, 2021. Owners may contact GMC customer service at 1-888-988-7267, Buick customer service at 1-866-608-8080, Chevrolet customer service at 1-800-222-1020 or Cadillac customer service at 1-800-458-8006. GM's number for this recall is N212329050.
POWER TRAIN:AUTOMATIC TRANSMISSION · 20V668000
2020-10-29
General Motors LLC (GM) is recalling certain 2018-2019 Chevrolet Cruze and Buick LaCrosse, 2018-2020 Chevrolet Equinox, Chevrolet Traverse and GMC Terrain, 2018 Chevrolet Malibu, 2019-2020 Buick Encore, Buick Enclave, Cadillac XT4, Chevrolet Blazer and GMC Acadia, and 2020 Cadillac XT6 vehicles. The start/stop accumulator endcap may have missing bolts.
Consequence: Missing bolts on the start-stop accumulator endcap could result in a transmission oil leak and may progress to a loss of propulsion, increasing the risk of a crash. A transmission fluid leak in the presence of an ignition source may increase the risk of fire.
Remedy: GM will notify owners, and dealers will inspect the start-stop transmission accumulator and replace it if any bolts are missing, free of charge. The recall began December 15, 2020. Owners may contact GMC customer service at 1-888-988-7267, Buick Customer service at 1-866-608-8080, Chevrolet customer service at 1-800-222-1020 or Cadillac customer service at 1-800-458-8006. GM's number for this recall is N202313440.
AIR BAGS:SIDE/WINDOW:CURTAIN:INFLATOR · 20V446000
2020-07-30
General Motors, LLC. (GM) is recalling certain 2020 Buick Enclave, Cadillac XT5 and XT6, Chevrolet Blazer, Silverado 1500, 2500 and 3500 and Traverse and GMC Acadia and Sierra 1500, 2500 and 3500 vehicles. The diffuser component of the Roof-Rail Air Bag (RRAB) inflator may not have been properly crimped to the inflator and could separate from the inflator during air bag deployment.
Consequence: If the diffuser separates from the inflator during deployment, RRAB performance may be degraded, increasing the risk of injury in a crash.
Remedy: GM will notify owners, and dealers will replace the suspect RRAB modules, free of charge. The recall began September 3, 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 N202305380.
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 Blazer 2.0L I4 Turbo and can vary by trim.
🔧 Built by master technician Chris Hackleman · Master Technician · 20+ years.