GMC · Known Issues
2023 GMC Sierra 3500HD Problems: 6 Known Issues
2023 model year · 280+ owner reports · Updated September 2026
2023 · All trims · All engines
Choose the year and equipment for your written issues and visual request.
2023 model year · 280+ owner reports · Updated September 2026
2023 · All trims · All engines
Choose the year and equipment for your written issues and visual request.
Interest applies to the selected vehicle and configuration; it is not a reservation. Voting stores a first-party identifier for up to 180 days to prevent repeat votes. No account or email is needed. Clearing cookies or using another device may count separately. Privacy
Visual coming soon
Your interest helps us choose what to build next.
Visual Known Issues · Coming soon
$4.99/month plus taxes at launch · No payment today
According to Au7o's analysis of 280+ owner reports, the 2023 GMC Sierra 3500HD has 6 documented known issues, with 4 rated critical. The most serious are Trailer brake controller / integrated trailer brake module malfunction ($80-$900 repair), Electric power steering (EPS) assist loss / reduced assist warnings (new body style), Rear Leaf Spring Breakage Under Heavy Loads ($400-$1,500 repair) and Diesel Injector Failure Causing White Smoke and Rough Running ($600-$5,000 repair). The most commonly reported issue is Trailer brake controller / integrated trailer brake module malfunction with 160 owner reports. Across all issues with published estimates, repair costs range from $80 to $5,000. DIY maintenance guides at au7o.io.
Don't see your problem? Describe your symptoms to get a diagnosis, or get a full repair guide.
According to Au7o's analysis of 280+ owner reports, the 2023 GMC Sierra 3500HD has 6 documented issues. The most frequently reported are: Trailer brake controller / integrated trailer brake module malfunction, Electric power steering (EPS) assist loss / reduced assist warnings (new body style), Rear Leaf Spring Breakage Under Heavy Loads. Of these, 4 are rated critical and should be addressed promptly.
The 2023 GMC Sierra 3500HD has 6 known issues documented across 280+ owner reports. 4 issues are rated critical: Trailer brake controller / integrated trailer brake module malfunction and Electric power steering (EPS) assist loss / reduced assist warnings (new body style) and Rear Leaf Spring Breakage Under Heavy Loads and Diesel Injector Failure Causing White Smoke and Rough Running. Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.
Repair costs for known GMC Sierra 3500HD issues range from $80 to $5,000, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, Trailer brake controller / integrated trailer brake module malfunction, typically costs $80-$900 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.
Sierra 3500HD owners towing heavy loads report intermittent trailer brake output loss, warning messages, or erratic gain behavior from the integrated trailer brake controller. NHTSA complaints and GM service bulletins/diagnostics commonly point to module/software issues, poor con… Repairs typically run $80-$900. Severity: high.
On 2020+ Sierra 3500HD (T1 platform) with electric power steering, owners report intermittent loss of steering assist and warning messages such as "Steering Assist Reduced". NHTSA complaints and GM service information commonly point to EPS module/software issues, wiring/connector… Severity: high.
The rear leaf spring packs on the Sierra 3500HD are prone to breaking or cracking under sustained heavy loads, particularly when used for frequent towing, hauling, or with fifth-wheel hitches. The main leaf or secondary leaves fracture at the spring eye or center bolt area. Broke… Repairs typically run $400-$1,500. Severity: high.
The Bosch piezoelectric fuel injectors on the Duramax L5P and LML engines can fail due to contaminated fuel, high-mileage wear, or internal electrical faults. A failed injector causes white smoke on startup, rough idle, misfires on the affected cylinder, and fuel dilution of the… Repairs typically run $600-$5,000. Severity: high.
The recirculating ball steering gear box on the Sierra 3500HD develops fluid leaks at the input shaft seal and sector shaft seal, leading to power steering fluid loss and increased steering play. The heavy-duty application and large tires accelerate wear on the steering box inter… Repairs typically run $400-$1,500. Severity: medium.
The cast iron exhaust manifolds on the Duramax diesel engine are prone to cracking and warping due to extreme exhaust gas temperatures and thermal cycling. Cracks typically develop at the manifold-to-head mounting points, causing exhaust leaks that produce a ticking noise on cold… Repairs typically run $800-$2,500. Severity: medium.
Content on this page was compiled with AI assistance using NHTSA complaints, TSBs, owner reports, and public automotive data. While we strive for accuracy, this information may contain errors. Always verify repair procedures and specifications with your vehicle's service manual or a qualified mechanic.