GMC TruckSierra 15002021Overview/gmc-truck/sierra-1500/2021/base/

2021 GMC Truck Sierra 1500

Factory specifications, fluid capacities, torque values, EPA fuel economy and the federal safety record for the 2021 Sierra 1500.

The 2021 GMC Sierra 1500, built on the current full‑size truck platform, is equipped with a power‑train that calls for 6.0 qt of engine oil and operates with either 5W‑30 or 0W‑30 viscosity grades, a detail that underscores its service‑interval design. While the model’s robust engineering is evident, its reliability record shows 521 owner‑reported complaints, with the engine identified as the most frequent issue area, and it has been subject to seven recalls to date. Positioned in the middle of the Sierra’s recent production run, this model year reflects a reliability profile that is neither the strongest nor the weakest in the line, indicating a balanced but cautious outlook for researchers assessing long‑term durability.

Model year20242021

Quick specs

Fluid capacities, tune-up values and fuel economy at a glance.

Engine oil capacity6.0 qtOEM · verified
Engine oil type5W-30 / 0W-30OEM · verified
Lug nut torque140 ft-lbsOEM · verified

Fitment & sizes

Replacement part sizes and factory part numbers — battery, bulbs, filters and belts.

From the factory this vehicle uses a BCI Only use AGM VRLA Battery vented to the outside of the vehicle. 49 · 850 CCA battery, OE oil filter 12731742. Each part links to every other vehicle that shares it, so a part you already stock may fit more of your fleet than you'd expect.

Battery groupBCI Only use AGM VRLA Battery vented to the outside of the vehicle. 49 · 850 CCAOEM · verified
Tire size255/70R17 112SOEM · verified
Wheel / rim8 inOEM · verified

OE service part numbers OEM · verified

Engine oil filter12731742 alt 12727115
Engine air filter84121219 alt 84121217
Fuel filter13539108
Spark plug12622441 alt 12688094
Battery88864542 alt 88864539
Front wiper blades84578275
Serpentine belt12658178 alt 12669858
Thermostat89018168 alt 55496127
Cabin air filter13508023

Service quick specs OEM factory data

Capacities, torques and tune-up values from the factory service manual.

This engine holds 6.0 qt of 5W-30 / 0W-30 engine oil. Torque lug nuts to 140 ft-lbs. The firing order is 1-8-7-2-6-5-4-3.

Lubricants & capacities

Automatic Transmission FluidATF
Automatic Transmission Fluid Capacity7.4 qt
Automatic Transmission FluidATF
Automatic Transmission Fluid Capacity8.1 qt
Automatic Transmission FluidATF
Automatic Transmission Fluid Capacity6.0 qt
Automatic Transmission FluidATF
Automatic Transmission Fluid Capacity6.0 qt

Engine torques

Crankshaft Position (CKP) Sensor Bolt(s)6.25 ft-lbs
Camshaft Position (CMP) Sensor Bolt(s)6.25 ft-lbs
Crankshaft Position (CKP) Sensor Bolt(s)6.25 ft-lbs
Camshaft Position (CMP) Sensor Bolt(s)6.25 ft-lbs
Crankshaft Position (CKP) Sensor Bolt(s)18.0 ft-lbs
Camshaft Position (CMP) Sensor Bolt(s)18.0 ft-lbs
Crankshaft Pulley and/or Damper Bolts43.0 ft-lbs
Cylinder Head InstructionsUse new bolts only.

Chassis torques

Lug Nuts140 ft-lbs
Transfer Case Fill Plug15.0 ft-lbs
Transfer Case Drain Plug15.0 ft-lbs

Ignition

Cylinder Firing Order1-3-4-2
Cylinder Firing Order1-5-3-6-2-4
Cylinder Firing Order1-6-5-4-3-2
Cylinder Firing Order1-8-7-2-6-5-4-3
Spark Plug ManufacturerAC Delco
Spark Plug Gap.025-.029 in
Spark Plug Torque12-13 ft-lbs
Spark Plug ManufacturerAC Delco

Battery & A/C

RefrigerantR1234yf
Refrigerant Capacity1.40 lbs
Oil GroupPAG
Oil Capacity3.30 oz
Standard BCI Cranking Performance850 cca
Standard BCI Cranking Performance730 cca
Standard BCI Cranking Performance730 cca
Standard BCI Group Number94R

Service checks

Key ON Engine OFF (KOEO)46.0-88.0
Key ON Engine OFF (KOEO)50.0-94.0
RPM43.0-58.0 rpm

Brakes

Brake Caliper Bolt to Carrier TorqueFront: NS, Rear: 30.0 ft-lbs
Brake Caliper Carrier to Hub Bolt TorqueRear: 118.0 ft-lbs
ABS Sensor Torque6.7
Vented Rotor Minimum Thickness for ReplacementFront: 1.102; Rear: .709
Vented Rotor Minimum Thickness after RefinishFront: 1.122; Rear: .728
Variation from Parallelism Thickness Variation.00024"
Maximum Rotor Runout.002"

Multi-step torque procedures OEM · verified

Camshaft Sprocket and/or Gear Bolt(s) — tightening sequence 1 stages
118.0 ft. lbs., Step 2: 50°18 ft. lbs
Connecting Rod (Large End) Bearings — tightening sequence 1 stages
118.0 ft. lbs., Step 2: 110°18 ft. lbs
Connecting Rod (Large End) Bearings — tightening sequence 1 stages
118.0 ft. lbs., Step 2: 110°18 ft. lbs
Connecting Rod (Large End) Bearings — tightening sequence 1 stages
115.0 ft. lbs., Step 2: 85°15 ft. lbs
Crankshaft Pulley and/or Damper Bolts — tightening sequence 1 stages
1Take old crankshaft balancer bolt and tighten to 240.0 ft. lbs., Step 2: Remove the old crankshaft balancer bolt and throw away., Step 3: Recess the nose of the crankshaft into the balancer bore: 0.94-0.176", Step 4: Use new crankshaft bolt: 110.0 ft. lbs., Step 5: Loosen 360°, Step 6: 59.0 ft. lbs. Step 7: Bolt with rotating washer: 200° or Bolt that has a flanged head: 125°240 ft. lbs
Crankshaft Pulley and/or Damper Bolts — tightening sequence 1 stages
1Take old crankshaft balancer bolt and tighten to 240.0 ft. lbs., Step 2: Remove the old crankshaft balancer bolt and throw away., Step 3: Recess the nose of the crankshaft into the balancer bore: 0.94-0.176", Step 4: Use new crankshaft bolt: 110.0 ft. lbs., Step 5: Loosen 360°, Step 6: 59.0 ft. lbs. Step 7: Bolt with rotating washer: 200° or Bolt that has a flanged head: 125°240 ft. lbs
Cylinder Head — tightening sequence 1 stages
1M12 Bolts22 ft. lbs
Cylinder Head — tightening sequence 7 stages
130.0 ft. lbs., Step 2: Completely Loosen Bolts 13, 14, 5, 6, 4, 3, 11 & 1230 ft. lbs
3Tighten Bolts30 ft. lbs
4Completely Loosen Bolts 9, 10, 1, 2, 7 & 8
5Tighten Bolts30 ft. lbs
6Bolts 1-1459 ft. lbs
7225°
811.0
Flex or Driveplate Bolts — tightening sequence 1 stages
111.0 ft. lbs., Step 2: 75°11 ft. lbs
Flex or Driveplate Bolts — tightening sequence 1 stages
126.0 ft. lbs., Step 2: 70°26 ft. lbs
Flex or Driveplate Bolts — tightening sequence 1 stages
111.0 ft. lbs., Step 2: 22.0 ft. lbs., Step 3: 45°11 ft. lbs
Intake Manifold to Engine Bolts — tightening sequence 1 stages
13.7 ft. lbs., Step 2: 7.43.7 ft. lbs
Intake Manifold to Engine Bolts — tightening sequence 1 stages
13.7 ft. lbs., Step 2: 7.43.7 ft. lbs

Factory maintenance schedule OEM · verified

Normal service, condensed from the factory interval matrix.

Under the factory schedule, replace the spark plugs every 97,500 mi; coolant at 150,000 mi. The big-interval services (at 150,000 mi for coolant, and the transmission fluid) are the ones owners most often skip — on a lower-mileage example, assume the original fluids are still in it and check them first.

Every 7,500 miAccelerator Pedal (inspect) · Body Latches, Locks & Hinges (lubricate) · Brake Shift Interlock Solenoid (inspect) · Brake System (inspect) · CV Joint Boot (inspect) · Engine Air Filter Element (inspect)
Every 15,000 miWindshield Wiper Blade (replace)
Every 22,500 miCabin Air Filter (replace)
Every 30,000 miFuel Filter (replace)
Every 45,000 miEngine Air Filter Element (replace) · Fuel Evaporative Emission Control System (inspect)
Every 75,000 miHood Hinge (inspect)
Every 97,500 miSpark Plug Wires (inspect) · Spark Plugs (replace) · Transfer Case Assembly (drain & refill)
At 150,000 miAccessory Drive Belt (inspect) · Engine Coolant System (drain, flush & refill) · Timing Belt (replace)

Reliability & federal safety record

Owner-reported issues, recalls, investigations and service bulletins on record with NHTSA — an unfiltered look at what owners actually experience.

Owner complaints about the 2021 GMC Truck Sierra 1500 dominate in one area — the engine, 169 of 521 reports (32%), well ahead of the next concern. None of this vehicle's 7 recall campaigns target the engine, so those reports read as owner-reported wear-and-tear rather than an acknowledged defect. 5 of the reports describe a crash and 6 a fire — a small share of the total, but worth weighing against the engine pattern above. These are tallies of what owners actually reported to the federal government, not an editorial score — and higher-selling models naturally rack up more reports.

7
Open recalls
NHTSA campaigns
1442
Service bulletins
Manufacturer communications
4
ODI investigations
Office of Defects Investigation
521
Owner complaints
5 involved a crash · 6 a fire
NHTSA crash-test rating federal NCAP · out of 5 stars
Overall★★★★★
Frontal★★★★
Side★★★★★
Rollover★★★★

Owner complaints filed with NHTSA, by component

All 521 complaints on record, top 8 components.

Engine169
Power Train64
Engine & Engine Cooling41
Power Train,Engine30
Electrical System26
Unknown Or Other16
Steering13
Unknown Or Other,Engine12

Source: NHTSA Office of Defects Investigation complaint database.

Recalls NHTSA · verified

Showing 2 of 7 campaigns on record for this vehicle.

20V792000Seat BeltsReported 17/12/2020

General Motors, LLC (GM) is recalling certain 2019-2021 Chevrolet Silverado 1500 and GMC Sierra 1500, 2021 Chevrolet Suburban and Tahoe and GMC Yukon XL and 2020-2021 Chevrolet Silverado 2500 and 3500 and GMC Sierra… Remedy: GM will notify owners, and dealers will inspect left-side and right-side front-row center seat-belt bracket attachments and reassemble it correctly as necessary, free of charge…

20V811000Seat BeltsReported 23/12/2020

General Motors, LLC (GM) is recalling certain 2020 Chevrolet Bolt EV and 2021 GMC Canyon and Sierra 1500, 2500 and 3500, Yukon, Yukon XL, Cadillac Escalade and Escalade ESV and Chevrolet Blazer, Camaro, Colorado… Remedy: GM will notify owners, and dealers will replace the suspect bolts, free of charge. The recall began January 29, 2021. Owners may contact GMC customer service at 1-800-462-8785…

Technical service bulletins NHTSA · verified

Showing 5 of 1442 bulletins on record with NHTSA.

BulletinDateComponentSummary
PIT6473F2026-07-17Unknown Or OtherThis PI was created to help avoid unnecessary front camera module replacements
PIT5767B2026-07-13Unknown Or OtherThis PI provides a diagnostic tip on poor a/c performance due to a condenser issue and…
PIT65322026-07-06Unknown Or OtherThe purpose of this PI is to inform dealer technicians of a normal cab pressure relief…
PIT5966F2026-06-23Unknown Or OtherThis Preliminary information communicates an issue with an OTA pending message still…
PIT65232026-06-10Unknown Or OtherThis PI provides diagnostic steps for dealer technicians to verify the condition and…

Common OBD-II trouble codes

The most common OBD-II codes for this vehicle's emissions system. These are standardized SAE J2012 definitions, not vehicle-specific fault reports.

P0420
Catalyst system efficiency below threshold — Bank 1
P0300
Random / multiple cylinder misfire detected
P0171
System too lean — Bank 1
P0455
Evaporative emission system leak detected — large leak
P0128
Coolant thermostat below regulating temperature
P0442
Evaporative emission system leak detected — small leak

VIN tools

Decode factory build data for a specific vehicle by VIN.

VIN
Decode a VIN to confirm the transmission and build data for a specific Sierra 1500. OEM
Build data
Plant, GVWR class, engine and body data for any 17-character VIN.
Recalls
Check open recall campaigns against a specific vehicle by VIN.

Vehicles with shared specs

Find every vehicle that shares this one's battery, bulbs, oil capacity, platform or parts.

Reference guides

Cross-vehicle references for the kinds of data on this page.

Frequently asked

How much oil does the 2021 Sierra 1500 take?

6.0 qt of Dexos 1 Gen 2 5W-30; Temperatures below -20°F 0W-30 may be used., per the factory manual.

Does the 2021 Sierra 1500 have open recalls?

NHTSA lists 7 recall campaign(s) for this model year. Check your specific vehicle by VIN.