Recall 18V352 affects 2,767 2017-2019 Thomas Built Buses Saf-T-Liner buses for loose brake caliper bolts. Repair is free at any franchised Thomas Built Buses dealer.
Thomas Built Buses is recalling 2,767 2017-2019 Saf-T-Liner C2, Saf-T-Liner Efx, and Saf-T-Liner Hdx school buses with air disc brakes because brake caliper mounting bolts can loosen. Loose caliper bolts can reduce braking performance and raise crash risk; Thomas Built Buses dealers will complete the recall repair free of charge.
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What's wrong?
On the 2017-2019 Thomas Built Buses Saf-T-Liner Efx, Saf-T-Liner C2, and Saf-T-Liner Hdx school buses in this recall, the brake caliper is the part that squeezes the brake pads against the disc rotor. The caliper mounting bolts hold that caliper in the correct position so the air disc brake can apply force evenly when the driver presses the brake pedal.
On affected buses, those mounting bolts were not tightened enough during assembly. A bolt that starts under-tightened can loosen as the bus is driven. If the caliper shifts, or if bolts loosen or fall out, the brake at that wheel does not apply as designed, which reduces braking effectiveness.
There is no warning sign before failure. A driver should not count on a sound, warning light, or change in pedal feel to identify this defect before the brake hardware loosens.
Who's affected?
Spans three Saf-T-Liner models across the 2017-2019 model years, all tied to the hydraulic brake system.
| 2019 Thomas Built Buses Saf-T-Liner Efx | hydraulic brake system |
|---|---|
| 2019 Thomas Built Buses Saf-T-Liner C2 | hydraulic brake system |
| 2017 Thomas Built Buses Saf-T-Liner Hdx | hydraulic brake system |
| 2019 Thomas Built Buses Saf-T-Liner Hdx | hydraulic brake system |
| 2017 Thomas Built Buses Saf-T-Liner Efx | hydraulic brake system |
| 2018 Thomas Built Buses Saf-T-Liner Hdx | hydraulic brake system |
| 2017 Thomas Built Buses Saf-T-Liner C2 | hydraulic brake system |
| 2018 Thomas Built Buses Saf-T-Liner C2 | hydraulic brake system |
| 2018 Thomas Built Buses Saf-T-Liner Efx | hydraulic brake system |
| Units affected | 2,767 |
| Field incidents | NHTSA has logged no field incidents to date. |
A matching year and model does not confirm inclusion. Check your VIN to confirm whether your specific bus is included.
What's the safety risk?
Loose brake caliper mounting bolts can reduce braking performance and increase the risk of a crash. Schedule the bolt inspection soon, and limit use of the bus until a dealer confirms the caliper bolts are tight. Repair is free at any franchised Thomas Built Buses dealer.
What should I do?
- Check your VIN to confirm your 2017-2019 Thomas Built Buses Saf-T-Liner Efx, Saf-T-Liner C2, or Saf-T-Liner Hdx bus is included in this recall.
- Contact your nearest franchised Thomas Built Buses dealer to schedule the free brake caliper mounting bolt inspection and tightening that addresses bolts tied to reduced braking performance.
- Bring the recall notice if you have it. If not, reference recall number 18V352 when you call.
- Drive cautiously until the repair is complete, leave extra following distance, and avoid hard braking when safe.
What happens at the repair
At the dealer, a Thomas Built Buses technician inspects the brake caliper mounting bolts on the affected school bus and tightens any bolts that are not secured to specification. The work is done at no charge under the recall. This repair focuses on the air disc brake caliper hardware, where loose mounting bolts can allow the caliper to move out of position. Ask the service desk to confirm the recall number and document the completed inspection before the bus returns to service.
Timeline
| May 29, 2018 | NHTSA published the recall |
|---|---|
| July 27, 2018 | Dealer notification began |
| July 27, 2018 | Dealer notification ended |
| July 27, 2018 | Interim owner notification (was planned for this date) |
| September 4, 2018 | Owner notification mailed |
Frequently asked questions
What is recall 18V352?
Recall 18V352 covers 2,767 2017-2019 Thomas Built Buses Saf-T-Liner Efx, Saf-T-Liner C2, and Saf-T-Liner Hdx school buses with air disc brakes. The brake caliper mounting bolts can loosen if they were not tightened enough. Dealers will inspect and tighten the bolts for free.
What should I do if my 2017-2019 Thomas Built Buses Saf-T-Liner Efx, Saf-T-Liner C2, or Saf-T-Liner Hdx is on this recall?
Check your VIN to confirm the specific bus is included in recall 18V352. If it is, contact a franchised Thomas Built Buses dealer to schedule the brake caliper mounting bolt inspection and tightening. Reference recall number 18V352 or DTNA recall FL-772 when you call.
Is the recall repair free?
Yes. Federal recall law requires the manufacturer to repair the defect at no cost. For recall 18V352, Thomas Built Buses dealers inspect the brake caliper mounting bolts and tighten them as needed, free of charge.
What is the safety risk for recall 18V352?
The safety risk is reduced braking performance. If the brake caliper mounting bolts loosen, the brakes can lose effectiveness, increasing the risk of a crash. The repair path is to have a franchised Thomas Built Buses dealer inspect and tighten the bolts for free.
When did the 18V352 repair become available?
The recall repair began September 4, 2018, after an interim owner notice was issued July 25, 2018. Since the remedy is available, included buses can be taken to a franchised Thomas Built Buses dealer for the free brake caliper mounting bolt inspection and tightening.
More information
| NHTSA campaign page | nhtsa.gov/vehicle-recalls/18V352000 |
|---|---|
| Thomas Built Buses customer service | 1-800-547-0712 |
| NHTSA recall # | 18V352 |
| NHTSA recall # (full) | 18V352000 |
Source documents
-
Download Misc. Document (PDF) - Download Recall Document (PDF) (PDF)
- Download Recall Investigation Document (PDF) (PDF)
- Download Owner Notification Letter (PDF)
- Download Owner Notice (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 25, 2026. RecallNotify does not paraphrase NHTSA's consequence language; that text is reproduced as written above. Editorial standards →