2020 GMC Sierra 1500 Engine Problems

NHTSA component category: ENGINE · data through 07/14/2026

210Engine complaints

48.2%Of all 436 complaints

#1Most-reported category

Source: U.S. NHTSA complaint data. Complaints are unverified reports from vehicle owners — a complaint is not a confirmed defect.

How engine ranks on this vehicle

ENGINE210 · 48.2%

POWER TRAIN85 · 19.5%

ELECTRICAL SYSTEM74 · 17%

SERVICE BRAKES47 · 10.8%

Unspecified / other42 · 9.6%

Share of the 436 complaints citing each category; one complaint can cite several. Full breakdown on the 2020 GMC Sierra 1500 overview page.

What owners report

“A VERY STRONG "AMMONIA" ODOR COMES INTO THE CABIN. THIS HAPPENS WHEN THE DEF FLUID IS GOING INTO THE EXHAUST SYSTEM FOR THE REGEN PROCESS…”NHTSA complaint 11459875 — filed 04/06/2022

“I have a lifters problem that the dealership takes more that three weeks to fixed without a loaner car, then i have electrical problems where…”NHTSA complaint 11449659 — filed 01/31/2022

“The contact owns a 2020 GMC Sierra 1500. The contact stated that shortly after refueling while driving under 15 MPH, the check engine and service…”NHTSA complaint 11442892 — filed 12/06/2021

Excerpts are shortened and scrubbed of personal details; they are individual, unverified reports.

Engine complaints by year filed

Frequently asked questions

Does the 2020 GMC Sierra 1500 have engine problems?

Engine is the most-reported problem area on the 2020 GMC Sierra 1500: 210 of 436 complaints on file (48.2%). Complaints are unverified owner reports, not confirmed defects.

How many complaints does the 2020 GMC Sierra 1500 have in total?

436 complaints were on file with NHTSA as of 07/14/2026. Across all categories, 11 involved a crash, 5 involved a fire, 13 reported injuries, and none reported deaths.

What does NHTSA's engine category include?

NHTSA assigns each complaint to standard component categories; this page reports the ENGINE category exactly as NHTSA defines and records it.

About this data — Complaint figures on this page are consumer reports submitted to the National Highway Traffic Safety Administration (NHTSA), a U.S. government agency. NHTSA does not verify individual complaints; a complaint is not proof that a defect exists, and counts reflect what owners chose to report, not confirmed failure rates. Recall information comes from official NHTSA safety recall campaigns; recall repairs are free at authorized dealers. Always check your specific vehicle by VIN at nhtsa.gov/recalls. CarModelProblems.com is an independent site and is not affiliated with NHTSA or any vehicle manufacturer. Data through 07/14/2026.