2018 GMC Sierra 2500: what breaks, and at what mileage
What breaks on the 2018 GMC Sierra 2500
On the 2018 GMC Sierra 2500, the failure owners report most often is other engine problem, with 7 reports on file. Across every failure mode on this year, half the dated reports were filed before 10,000 miles. Overall it scores 73 out of 100, high risk for a 2018.
High risk for a 2018 — 166th riskiest of the 251 2018 vehicles we can rate. 46 owner reports; fleet size estimated from this year's own recall paperwork.
What breaks on the 2018 GMC Sierra 2500
Owners have reported 18 named failure modes on the 2018 GMC Sierra 2500, and the three most-reported carry 35% of everything filed, which is an unusually even spread for one model year.
Other engine problem leads with 7 reports and about 0.4 per 1,000 vehicles.
Other electrical problem follows with 5 reports, median 45,000 miles. 1 of those report mention a fire.
Other powertrain problem follows with 4 reports, median 10,000 miles.
By system, the reports fall mostly into engine (7), electrical (5) and fuel (5).
When these failures get reported
14 of the reports on the 2018 GMC Sierra 2500 came with an odometer reading, and half of those were filed before 10,000 miles.
The busiest stretch is between 0 and 10,000 miles, which alone holds 50% of the dated reports.
79% of the dated reports were filed below 36,000 miles, which is early enough that a fair number of these cars were still under a factory warranty when the owner complained.
Tick median reported mileage Solid middle half of reports Faint 10th to 90th percentile Colour how bad the failure is when it happens
Showing the 12 most-reported failure modes of 18. The full list is in the table below.
How reports accumulate
Every report with an odometer reading, cumulative, from 0 to 200,000 miles. A curve that climbs early is a car with early problems, whatever its total.
- Line share of reports filed by that mileage
- Dashed the median reported mileage
How bad it is when it goes
Across the named modes, 2 a fire. Those are the words owners used in their own complaints, and NHTSA does not verify them, but they are the closest thing in this data to a measure of what a failure actually did.
The average severity weight across every report on this year is 3.54, where a stalled engine or a failed airbag weighs many times more than a rattling trim panel, and a figure this high means the reports are dominated by failures with safety consequences rather than annoyances. The weighting is set out in full on the methodology page.
What the top failures cost to put right, as editorial estimates for an independent US shop rather than figures from NHTSA: other engine problem at $300–$4,000, other electrical problem at $250–$2,000, other powertrain problem at $400–$4,500 and other body or interior problem at $200–$2,000. Dealer labour, a seized bolt or a part that is no longer made can push any of these past the top of its range.
28% of the reports on this year sit in the engine, transmission, drivetrain or cooling systems — the four where a repair bill is usually four figures.
Every reported failure mode
| Failure mode | System | Reports | With reading | 25th | Median | 75th | Per 1,000 | Typical repair | Severity |
|---|---|---|---|---|---|---|---|---|---|
| Other engine problem | engine | 7 | 1 | — | 6k | — | 0.4 | $300–$4,000 | High |
| Other electrical problem | electrical | 5 | 1 | — | 44k | — | 0.3 | $250–$2,000 | Moderate |
| Other powertrain problem | transmission | 4 | 2 | — | 10k | — | 0.2 | $400–$4,500 | High |
| Other body or interior problem | body | 4 | 1 | — | 31k | — | 0.2 | $200–$2,000 | Moderate |
| Tire blowout or tread separation | wheels | 3 | 1 | — | 8k | — | 0.2 | $200–$1,500 | Critical |
| Other fuel system problem | fuel | 3 | 0 | — | — | — | 0.2 | $300–$2,200 | High |
| Other lighting problem | lighting | 3 | 2 | — | 9k | — | 0.2 | $120–$1,200 | Moderate |
| Overheating | cooling | 2 | 1 | — | 12k | — | 0.1 | $400–$3,500 | High |
| Other visibility problem | glass | 2 | 0 | — | — | — | 0.1 | $150–$1,400 | Moderate |
| Fuel pump failure | fuel | 1 | 1 | — | 48k | — | 0.1 | $600–$2,600 | High |
| Fuel injector failure | fuel | 1 | 1 | — | 4k | — | 0.1 | $450–$2,800 | Moderate |
| Backup camera failure | infotainment | 1 | 1 | — | 1k | — | 0.1 | $250–$1,200 | Moderate |
| Seat belt or retractor failure | airbag | 1 | 1 | — | 4k | — | 0.1 | $200–$900 | High |
| Headlight failure or clouding | lighting | 1 | 1 | — | 40k | — | 0.1 | $150–$1,800 | Moderate |
| Other brake problem | brakes | 1 | 0 | — | — | — | 0.1 | $300–$1,800 | High |
| Other steering problem | steering | 1 | 0 | — | — | — | 0.1 | $350–$2,400 | High |
| Other wheel or tire problem | wheels | 1 | 0 | — | — | — | 0.1 | $200–$1,500 | High |
| Other driver assistance problem | adas | 1 | 0 | — | — | — | 0.1 | $250–$1,800 | High |
| Unclassified problem | other | 4 | 0 | — | — | — | 0.2 | — | Moderate |
Rate per 1,000 uses a fleet-size estimate derived from recall paperwork for this exact model year. It is a lower bound. Repair costs are typical independent-shop ranges for the failure, not figures from these reports.
How often, against how many were built
Scaled by an estimate of how many of these cars exist, the 2018 GMC Sierra 2500 draws about 2.5 per 1,000 vehicles, which puts it in the 79th percentile of complaint rates among 2018 vehicles we can rate.
That denominator is the weakest number on the page and it is fair to say so plainly. Rate per 1,000 uses a fleet-size estimate derived from recall paperwork for this exact model year. It is a lower bound.
The working figure is 18,778 vehicles. If the true number is twice that, every rate on this page is half what it says; the ranking against other 2018 vehicles, which is what the risk score uses, is far more robust than the rate itself.
Recalls on the 2018 model year
NHTSA has issued 5 recall campaigns covering the 2018 GMC Sierra 2500, affecting an estimated 36,579 vehicles. A recall is a different kind of evidence from a complaint: it is the regulator and the manufacturer agreeing that something has to be fixed, and the fix is free for as long as the car exists.
The campaigns cover air bags:side/window:curtain:inflator, fuel system, diesel:storage:tank assembly, equipment:electrical:engine block heater and engine. Whether the work was actually done on the car in front of you is a question only the VIN can answer, and the manufacturer or NHTSA will answer it free.
Recalls also distort complaint counts. Publicity about a campaign reminds owners that complaining is possible, so reports for a recalled component often spike after the recall rather than before it.
AIR BAGS:SIDE/WINDOW:CURTAIN:INFLATOR
2,061 vehicles 2024-10-10- Defect
- General Motors, LLC (GM) is recalling certain 2018 Chevrolet Silverado 1500, GMC Sierra 1500, 2018-2019 Chevrolet Silverado 2500, 3500, and GMC Sierra 2500, 3500 Crew Cab trucks. The left or right-side roof-rail air bag (RRAB) inflator end cap may detach from the inflator or the inflator sidewall may rupture.
- Consequence
- A separated inflator end cap or inflator rupture can allow compressed gas to escape, resulting in the end cap or other components being propelled into the vehicle, increasing the risk of injury or crash.
- Remedy
- Dealers will replace the left and right side RRAB modules, free of charge. Owner notification letters were mailed November 8, 2024. Owners may contact Chevrolet customer service at 1-800-222-1020, and GMC Customer Service at 888-988-7267. GM's number for this recall is N242474500.
FUEL SYSTEM, DIESEL:STORAGE:TANK ASSEMBLY
22,132 vehicles 2023-02-02- Defect
- General Motors, LLC (GM) is recalling certain 2017-2019 Chevrolet Silverado 2500, 3500, and GMC Sierra 2500, 3500 vehicles equipped with a dual fuel tank option. The rear fuel tank may collapse and prevent the fuel pump from transferring fuel to the front tank, resulting in an engine stall.
- Consequence
- An engine stall increases the risk of a crash.
- Remedy
- Dealers will inspect the fuel tank and fuel pump module, replacing them as necessary. Dealers will also add a vent hose to the rear tank assembly. Repairs will be performed free of charge. An interim owner notification letter informing owners of the safety risk was mailed on March 15, 2023. Owner notification letters were mailed June 21, 2023. Owners may contact Chevrolet customer service at 1-800-222-1020 or GMC customer service at 1-800-462-8782. GM's number for this recall is N222368030.
EQUIPMENT:ELECTRICAL:ENGINE BLOCK HEATER
338,020 vehicles 2021-07-01- Defect
- General Motors, LLC (GM) is recalling certain 2017-2019 Chevrolet Silverado 2500, 3500 and 2017-2019 GMC Sierra 2500 and 3500 vehicles equipped with a Duramax diesel 6.6 liter engine and an optional engine-block heater cord. An electrical short-circuit may occur in the engine-block heater cable or in the terminals that connect the heater cable to the block heater.
- Consequence
- An electrical short-circuit can increase the risk of a fire.
- Remedy
- Dealers will replace engine block heaters and heater cords. Vehicles that have this feature disabled as a remedy to the safety condition will be contacted and offered replacement block heaters and heater cords under a separate customer satisfaction program, free of charge. GM will provide free replacement block heaters and cords under a separate customer satisfaction campaign. For vehicles previously included in recall 19V-328, the heater cord will be replaced and rerouted, free of charge. Interim owner notifications were mailed on August 13, 2021. Owner notification…
ENGINE
318,374 vehicles 2019-04-25- Defect
- General Motors LLC (GM) is recalling certain 2019 Chevrolet Silverado 4500, 5500 and 6500 vehicles and 2017-2019 Chevrolet Silverado 2500 and 3500 vehicles and GMC Sierra 2500 and 3500 vehicles equipped with Duramax 6.6 liter diesel engines and an optional engine-block heater. The engine block heater cord or the terminals that connect the heater cord to the block heater may short circuit and fail.
- Consequence
- A short-circuit may damage the engine components and increase the risk of fire.
- Remedy
- GM will contact owners, dealers will replace the engine block heater, free of charge. Additionally, in Chevrolet Silverado 2500 and 3500 vehicles, dealers will install a new rerouted heater cord. The recall began December 11, 2019. Owners may contact GM customer service at 1-586-596-1733. GM's number for this recall is N182206310.
SEAT BELTS:FRONT:RETRACTOR
38,048 vehicles 2017-09-14- Defect
- General Motors (GM) is recalling certain 2017-2018 Chevrolet Silverado 2500 and 3500 and GMC Sierra 2500 and 3500 trucks. The front seat belt retractor assemblies were built with the incorrect torsion bar. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 209, "Seat Belt Assemblies."
- Consequence
- The seat belt retractors may not perform as intended during a crash, increasing the risk of injury.
- Remedy
- GM will notify owners, and dealers will replace both front seat belt retractor assemblies, free of charge. The recall began March 24, 2021. Owners may contact GMC customer service at 1-888-988-7267 or Chevrolet customer service at 1-800-222-1020. GM's numbers for this recall are 17368, 17375, and 17376.
Recall work is free at a franchised dealer regardless of the car's age. Check the VIN at nhtsa.gov/recalls before assuming it was done.
How it ranks in the 2018 field
The score at the top of the page, placed among its peers. The zones are the same thresholds the scorer applies, read out of the scorer itself, so the picture and the band word cannot disagree.
Scores are ranked within the model year, never across years, because an older car has had longer to accumulate reports.
- Left fewer and less serious reports
- Right more, or worse
- Marker this vehicle
Better and worse years of the same car
High risk for a 2018 — 166th riskiest of the 251 2018 vehicles we can rate. The comparison is always within the same model year, so an older car is never penalised for having had longer to break.
Across the 27 model years of this car that carry enough reports to score, 2007 comes out best at 63 and 2025 worst at 81, with 2018 itself at 73.
If the model year is negotiable, 2007, 2013, 2012, 2009, 2008, 2014, 2021, 2000, 2023, 2011, 2015, 1999 and 1998 score lower than 2018 by a margin worth acting on. Same body, same engines, different luck — usually a supplier change or a mid-cycle fix, which the complaint data can show but never explain.
Within the 2017–2023 generation specifically, 2021 is the strongest year at 66 and 2019 the weakest at 77.
Scores compare each year against other cars of the same model year, so a low number on an older car is a real result and not an artefact of age.
Shorter is better. Years with too few reports to score are shown without a bar rather than as a zero, because no data is not good news.
Within the 2017-2023 generation, 2021 GMC Sierra 2500 scores best at 66 and 2019 GMC Sierra 2500 worst at 77.
What this page cannot tell you
46 owner reports; fleet size estimated from this year's own recall paperwork. Every count on this page is therefore a floor: it is the number of owners who went to the trouble of filing with a federal agency, which is a small and self-selected fraction of the owners who had the fault.
Of those 46 reports, 14 carried an odometer reading, so the mileages here describe 30% of the sample rather than all of it. Owners also round: readings pile up on multiples of ten thousand, which is why this site publishes "about 90,000 miles" and not "91,438".
Named failure modes come from matching phrases in the complaint text, so a badly worded complaint can land in the wrong bucket. The effect washes out across hundreds of reports and does not wash out across five.
And nothing here predicts what one car will do. These are other people's complaints, filed years apart, on cars maintained by strangers. Read the page as a map of where this model year has previously gone wrong, then have the specific car in front of you inspected.
Questions this page answers
What are the most common problems with the 2018 GMC Sierra 2500?
The most-reported failures are other engine problem (7 reports, median 5,000 miles), other electrical problem (5 reports, median 45,000 miles) and other powertrain problem (4 reports, median 10,000 miles). Counts come from owner complaints filed with NHTSA, which are voluntary, so they show what owners bothered to report rather than every fault that occurred.
Is the 2018 GMC Sierra 2500 reliable?
It scores 73 out of 100 on our risk index, which is high — 166th riskiest of the 251 2018 vehicles we can rate. The score is a comparison against other 2018 vehicles, not a prediction about any individual car, and it is built from complaint rates, severity and how early failures appear.
Which year of the GMC Sierra 2500 is best?
Within the 2017–2023 generation, 2021 scores best at 66 out of 100 and 2019 worst at 77. Same body, same engines, different luck.
Where this comes from. Every figure above is computed from NHTSA owner complaints and recall records for this exact make, model and year. Complaints are voluntary and self-selected, so treat counts as a floor. The methodology page writes out each formula, and the same numbers are available as JSON.
What breaks at my mileage Compare with another car
Source Owner complaints and recall records published by the US National Highway Traffic Safety Administration, model years 1996–2027 Figures rebuilt Published by AtWhatMileage How every figure is computed