2020 GMC Sierra 1500 Service and Repair Manual
2020 GMC Sierra 1500 service and repair manual — a detailed, factory-style reference for maintenance, diagnostics, and repair. Use it to confirm correct procedures, specifications, and system coverage before you start work.
Designed for technicians and DIY owners, this manual helps you troubleshoot accurately, follow step-by-step repair procedures, and reference wiring diagrams and system sections quickly while you work.
What’s included
- Step-by-step repair procedures and service information
- Specifications and reference data (where provided)
- Wiring diagrams and electrical sections
- Powertrain, brakes, steering, suspension, HVAC and more
Trims covered
- AT4 Crew Cab Pickup 4-Door
- Base Standard Cab Pickup 2-Door
- SLT Crew Cab Pickup 4-Door
- Base Extended Cab Pickup 4-Door
- Denali Crew Cab Pickup 4-Door
- SLE Crew Cab Pickup 4-Door
- Base Crew Cab Pickup 4-Door
- SLT Extended Cab Pickup 4-Door
- SLE Extended Cab Pickup 4-Door
- AT4 Extended Cab Pickup 4-Door
- Elevation Crew Cab Pickup 4-Door
- Elevation Extended Cab Pickup 4-Door
Engines covered
- 5.3L 5328CC 325Cu. In. V8 GAS OHV Naturally Aspirated
- 6.2L 6162CC 376Cu. In. V8 GAS OHV Naturally Aspirated
- 3.0L 2993CC 183Cu. In. l6 DIESEL DOHC Turbocharged
- 5.3L 5328CC 325Cu. In. V8 FLEX OHV Naturally Aspirated
- 4.3L 262Cu. In. V6 GAS OHV Naturally Aspirated
- 2.7L 2720CC 166Cu. In. l4 GAS DOHC Turbocharged
Index / Table of contents
- Body
- Brakes
- Chassis Electrical
- Driveline
- Engine Cooling
- Engine Electrical
- Engine Mechanical
- Engine Performance & Emission Controls
- Fuel System
- General Information & Identification
- Heating, Ventilation, & Air Conditioning
- Hybrid & Electric Vehicle Systems
- Steering
- Suspension
- Transmission, Clutch, & Transfer Case
- Wiring Diagrams
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 vehi
If the diffuser separates from the inflator during deployment, RRAB performance may be degraded, inc
GM will notify owners, and dealers will replace the suspect RRAB modules, free of charge. The recal
General Motors LLC (GM) is recalling certain 2020 Chevrolet Silverado 1500 and GMC Sierra 1500 vehicles. The bolts used to attach the front and/or rear brake calipers may have not been heat treated a
Broken caliper bolts can reduce brake performance or interfere with wheel rotation and increase the
GM will notify owners, and dealers will replace the brake caliper bolts, free of charge. The recall
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 S
Over cured tires may develop a break in the sidewall resulting in sudden air loss or a belt edge sep
GM will notify owners, and dealers will inspect the tires, replacing them as necessary, free of char
General Motors LLC (GM) is recalling certain 2019-2020 Chevrolet Silverado 1500 and GMC Sierra 1500 and 2020 Chevrolet Silverado 2500 trucks. One of the driveshaft joints may not have been properly w
If the driveshaft separates, there may be a loss of propulsion, increasing the risk of crash.
GM will notify owners, and dealers will replace the driveshaft, free of charge. The recall is expec
General Motors LLC (GM) is recalling certain 2020 Cadillac Escalade, Escalade ESV, Chevrolet Camaro, Silverado 1500, Suburban, Tahoe, GMC Sierra 1500, Yukon, and Yukon XL vehicles. The fuel pump may
Over-pressurization can crack the fuel pump and cause leaks, increasing the risk of a fire in the pr
GM will notify owners, and dealers will replace the fuel pump, free of charge. The recall began Dec
General Motors (GM) is recalling certain 2019-2021 GMC Sierra 1500 and Silverado 1500 vehicles equipped with certain accessory road tires and a 17" spare tire. The 17" spare tire provided with the ve
An ABS system that does not function properly can increase the risk of a crash.
Dealers will provide a new 17" spare tire and wheel assembly that is compatible with the accessory w
General Motors LLC (GM) is recalling certain 2019-2020 Chevrolet Silverado 1500 and GMC Sierra 1500, and 2020 Silverado 2500, Silverado 3500, Sierra 2500, and Sierra 3500 vehicles equipped with carpet
A vehicle fire could result if materials ignite inside the vehicle.
GM will notify owners, and dealers will close off the opening in the pretensioner bracket, free of c
General Motors LLC (GM) is recalling certain 2019-2020 Chevrolet Silverado 1500 and GMC Sierra 1500 trucks. The battery positive (B+) cable rings may have been manufactured with excessive glue, poten
An intermittent electrical connection between the B+ battery cable and the alternator could cause th
GM will notify owners, and dealers will inspect for the presence of glue or other contamination at t
General Motors LLC (GM) is recalling certain 2020 Buick Enclave, Cadillac XT5, GMC Acadia and Chevrolet Traverse vehicles and 2020-2021 Chevrolet Silverado 1500, GMC Sierra 1500 vehicles. The vehicle
Overcured tires may experience a carcass break in the sidewall resulting in a sudden air loss or cou
GM will notify owners, and dealers will inspect vehicles and replace tires that have DOT number and
The document advise technicians after an engine repair involving removal of the camshaft actuators, the vehicle may set p1101 P0172 and or stalls when taken off idle. The technician is instructed to verify the intake and exhaust camshaft ac
This PI provides diagnostic tips for diagnosing electric trailer brakes issues.
This PI provide diagnostic tip for an SES MIL with DTC P16A7 and/or P16AF. Dealers are to inspect for a loose connection.
This Preliminary information communicates that some customers may comment that after an auto-stop event the engine does not restart and to inspect the engine ground strap. Temporarily on hold while PIE0572 is active. PIE0572 has now ended a
This preliminary information communicates information about how to determine if a wheel and tires size change is available.
This PI was created to help avoid unnecessary front camera module replacements
This PI was created to help avoid unnecessary front camera module replacements
This PI was created to help avoid unnecessary front camera module replacements
Showing the 8 most recent of 1436 technical service bulletins on file with NHTSA.
I investigated and Unintended Acceleration crash that occurred on 8-9-2021. The vehicle had just left a body shop where it had repairs to the left front of the vehicle near the ECM. The driver reporte
This vehicle was involved in a fatal crash when it rear ended an SUV stopped at a red traffic light. The driver alleges mechanical failure of the brakes. Police performed a vehicle download which ca
Driving on state highway at posted speed. A deer ran into the right front and side of vehicle. Side airbags deployed. When the right side airbag deployed, it burned a hole in my passengers winter coat
The contact owns a 2020 GMC Sierra. The contact proceeded through the intersection when a vehicle crashed into the contact's driver's side door and wheel at unknown speeds. The contact stated that the
TL* THE CONTACT OWNS A 2020 GMC SIERRA 1500. THE CONTACT STATED THAT WHILE DRIVING APPROXIMATELY 35 MPH THE DRIVER LOST CONTROL OF THE VEHICLE AND DROVE OFF THE ROAD AND DOWN AN EMBANKMENT BEFORE CRAS
Showing the 5 most serious of 630 complaints filed with NHTSA.
