Is Your Catalytic Converter Still Under Warranty? The Federal 8-Year, 80,000-Mile Rule
Reviewed 2026-10-03. Checked against the sources listed below. This is general information, not a substitute for a mechanic's inspection.
Quick answer
Under federal rules, the emission warranty on cars and light trucks runs 2 years or 24,000 miles in general, but 8 years or 80,000 miles for a failed specified major emission control component, and catalytic converters are on that list. The clock starts on the date the vehicle was first delivered to its first buyer, and it ends at 8 years or 80,000 miles, whichever comes first. If your vehicle might still be inside that window, ask the dealer before you buy a converter.
The two warranty periods
| Coverage | How long | What it covers |
|---|---|---|
| General emission warranty | 24 months or 24,000 miles | Emission-related parts in general |
| Major component warranty | 8 years or 80,000 miles | Specified major components, including catalytic converters and the emission control computer |
When does the clock start?
The regulation says the warranty period begins on the date the vehicle is delivered to its ultimate purchaser. If it was first used as a demonstrator or company car, it starts on the date it was first placed in service. So a 2019 model year truck sold new in mid-2019 is covered until mid-2027, unless it passes 80,000 miles first.
When does it apply?
The federal regulation ties this performance warranty to a vehicle that fails an EPA-approved emissions test while it is within the warranty period, where the failure needs repair. In practice:
- Your vehicle fails an approved emissions test, or the dealer finds a failed converter.
- You are within 8 years and 80,000 miles from first delivery.
- The dealer for your vehicle's brand diagnoses it and makes the claim with the manufacturer.
Manufacturers can refuse a claim if the failure was caused by things like misuse, accident damage or poor maintenance, so keep your service records.
Quick check: are you still covered?
| Question | Where to find the answer |
|---|---|
| When was it first delivered? | The original sales paperwork, or ask a dealer to look up the in-service date from your VIN |
| How many miles? | Your odometer |
| What does your warranty booklet say? | The booklet that came with the vehicle. Some states, such as California, have their own rules and coverage |
If you are out of warranty
Most vehicles that need a converter are past 8 years or 80,000 miles. Then the usual path is a replacement converter that is legal in your state, made for your exact year, model and engine. Fix the cause of the failure first, such as misfires, oil burning or exhaust leaks, so the new converter lasts.
Related guides
- How long does a catalytic converter last?
- Direct-fit vs universal catalytic converter
- Readiness monitors explained
