Heavy Duty Emissions Testing
Our diesel smog check service specializes in heavy-duty vehicle emissions testing. We have the equipment, expertise, and certification to test commercial trucks, diesel passenger vehicles, and heavy equipment.
Diesel emissions testing is more complex than gasoline testing, requiring specialized diagnostic equipment and trained technicians familiar with diesel emissions systems.
We Test:
- Diesel passenger cars (1998 and newer)
- Light-duty diesel trucks (under 14,500 lbs)
- Commercial delivery vehicles
- Diesel RVs and motorhomes
Diesel Testing Features
OBD-II Diagnostics
Advanced computer diagnostic scans
Visual Inspection
Emissions control system verification
Specialized Equipment
Heavy-duty diagnostic tools and adapters
Diesel Test Pricing
💰 Fleet discounts available - call for details
Diesel Testing Process
Vehicle Assessment
Verify vehicle weight class, model year, and testing requirements.
OBD-II Diagnostic
Computer scan for emissions system codes and readiness monitors.
Visual Inspection
Check emissions control equipment, exhaust system, and fuel system integrity.
Certification
Issue certificate and submit results electronically to DMV.
Diesel Vehicles We Test
Passenger Cars
Diesel cars 1998 and newer including Volkswagen TDI, Mercedes, BMW, and other diesel sedans and wagons.
- • VW TDI models
- • Mercedes diesel cars
- • BMW diesel vehicles
- • Audi TDI models
Light Trucks
Light-duty diesel trucks under 14,500 lbs GVWR including pickup trucks and delivery vehicles.
- • Diesel pickup trucks
- • Commercial vans
- • Box trucks
- • Delivery vehicles
RVs & Motorhomes
Diesel recreational vehicles and motorhomes within weight limits for smog check requirements.
- • Class A motorhomes
- • Class C RVs
- • Diesel pusher coaches
- • Converted buses
Diesel Testing Requirements
What Makes Diesel Testing Different
More Complex Systems
Diesel vehicles have additional emissions control systems like DEF (diesel exhaust fluid), DPF (diesel particulate filter), and EGR systems that require specialized testing.
Extended Test Time
Diesel testing typically takes 25-35 minutes due to the comprehensive nature of emissions system diagnostics and visual inspections.
Weight Classifications
Testing requirements vary based on vehicle weight class (GVWR). We handle light-duty diesel vehicles up to 14,500 lbs.
Before You Come In
Check DEF Levels
Ensure diesel exhaust fluid is at proper levels
Drive Before Testing
Drive 20+ miles to ensure DPF regeneration cycle
Clear Any Codes
Address check engine lights before testing
Diesel Smog Check FAQ
Do all diesel vehicles need smog checks?
Diesel vehicles 1998 and newer with GVWR under 14,500 lbs need smog checks. Heavy trucks over this weight are exempt.
Why does diesel testing cost more?
Diesel testing requires specialized equipment, longer testing time, and more complex diagnostics compared to gasoline vehicles.
What if my DEF light is on?
Vehicles with DEF system warnings or low DEF fluid will not pass. Refill DEF and clear codes before testing.
Can you test deleted or modified diesels?
No, we cannot test vehicles with emissions equipment removed or modified. All factory emissions systems must be intact.
How often do diesels need testing?
Most diesel vehicles need smog checks every 2 years for registration renewal, same as gasoline vehicles.
What about DPF regeneration?
Drive your vehicle on the highway for 20+ miles before testing to ensure the DPF has completed a regeneration cycle.
Ready for Diesel Testing?
Professional diesel smog testing in Rancho Cordova. Call ahead for large vehicles or fleet testing.