Recall 16V657 covers 114 2017 Thomas Built Buses Saf-T-Liner C2 buses for a CNG filling-valve fuel leak. Franchised dealer repair is free.
Thomas Built Buses is recalling 114 2017 Saf-T-Liner C2 school buses with CNG engines because a filling-valve seal can dislodge during fast fueling and let fuel leak after the tank is filled. A fuel leak near an ignition source raises fire risk, and Thomas Built Buses dealers will complete the recall repair free of charge.
Does this recall apply to your specific vehicle?
The official, free per-VIN recall check is run by NHTSA. Enter your VIN and we'll forward you directly — and add you to a free watchlist so you hear about new recalls for your vehicle.
Check my VIN at NHTSARecallNotify doesn't check your VIN — NHTSA's official tool does. We use your email only to alert you to new recalls.
Watch this vehicle for recalls
Add it to your free watchlist and we will alert you as new federal recalls are posted for your year, make and model. New-recall alerts are rolling out now.
You are on the watchlist.
We will email you as new federal recalls are posted for your vehicle.
What's wrong?
The CNG filling valve on the 2017 Thomas Built Buses Saf-T-Liner C2 is part of the fuel storage system. During refueling, the valve accepts compressed natural gas from the fueling hose and directs it into the tank assembly. Its internal seal is supposed to stay seated so the fuel path closes after the tank is filled.
On buses built with the affected CNG fuel valves, a fast fuel fill can knock that internal seal out of position. Once the seal dislodges, the valve no longer closes the way it was designed to close. That leaves CNG escaping from the tank area after refueling instead of staying contained in the fuel system.
There is no warning sign before failure. The problem happens during the filling process, so the bus does not give the driver an advance signal that the seal is about to move out of place.
Who's affected?
| 2017 Thomas Built Buses Saf-T-Liner C2 | fuel system |
|---|---|
| 2017 Thomas Built Buses Saf-T-Liner C2 | fuel system |
| Units affected | 114 |
Not every 2017 Thomas Built Buses Saf-T-Liner C2 bus is on the list. Check your VIN to confirm whether your specific bus is included.
What's the safety risk?
A fuel leak near an ignition source raises the risk of a fire. Because this campaign involves fuel leakage, confirm the repair status before putting the bus back in regular service, especially if the vehicle was bought used or has incomplete service paperwork. Repair is free at any franchised Thomas Built Buses dealer.
What should I do?
- Check your VIN to confirm your 2017 Thomas Built Buses Saf-T-Liner C2 is included in this recall.
- Contact a franchised Thomas Built Buses dealer to confirm the free fuel-system repair that addresses the CNG filling-valve seal and fuel leak.
- Ask the dealer to verify the recall completion record if you did not receive a notice.
- Avoid ignition sources around the bus if fuel is leaking after a CNG fill until the repair is confirmed complete.
- Call Thomas Built Buses customer service at 1-800-547-0712 with questions and reference recall number 16V657 and Thomas Built Buses recall FL-720.
What happens at the repair
Thomas Built Buses says DTNA has already notified every affected owner and remedied every affected bus, so separate owner notification letters are not being issued for campaign FL-720. If a 2017 Saf-T-Liner C2 still shows this recall as open, the service desk should verify the completed repair record or arrange the free recall work. The repair addresses the CNG fast fill valve condition tied to fuel leakage after filling. Owners can contact DTNA customer service at 1-800-547-0712 with recall number FL-720 if the dealer record does not match the bus.
Timeline
| September 13, 2016 | NHTSA published the recall |
|---|---|
| November 2, 2016 | Owner notification mailed |
Frequently asked questions
What is recall 16V657?
Recall 16V657 covers 114 2017 Thomas Built Buses Saf-T-Liner C2 school buses with CNG engines. During a fast fuel fill, an internal seal in the filling valve can dislodge and allow fuel to leak after the tank is filled. A fuel leak near an ignition source increases fire risk.
What should I do if my 2017 Thomas Built Buses Saf-T-Liner C2 is on this recall?
Check your VIN to confirm whether your specific bus is included in recall 16V657. If it is, contact a franchised Thomas Built Buses dealer or customer service at 1-800-547-0712 and reference recall FL-720. The filing says all affected vehicles have been repaired.
Is the recall repair free?
Yes. Federal recall law requires the manufacturer to repair the defect at no cost. For recall 16V657, the filing says all affected Thomas Built Buses Saf-T-Liner C2 school buses have already been remedied.
What is the safety risk?
The safety risk is fire. The filling valve seal can dislodge during a fast CNG fill, allowing fuel to leak after the tank is filled. If leaked fuel reaches an ignition source, the risk of a fire increases.
What if I bought this bus used?
The recall follows the VIN, not the first owner. If you bought a 2017 Thomas Built Buses Saf-T-Liner C2 used, check your VIN to confirm whether it was included in recall 16V657 and whether the repair record is complete.
More information
| NHTSA campaign page | nhtsa.gov/vehicle-recalls/16V657000 |
|---|---|
| Thomas Built Buses customer service | 1-800-547-0712 |
| NHTSA recall # | 16V657 |
| NHTSA recall # (full) | 16V657000 |
Source documents
-
Download Misc. Document (PDF) - Download Recall Report (PDF)
- Download Quarterly Report (PDF)
- Download Recall Acknowledgement (PDF)
This article is generated from NHTSA's primary recall filings and reviewed against the source on May 31, 2026. RecallNotify does not paraphrase NHTSA's consequence language; that text is reproduced as written above. Editorial standards →