NHTSA Office of Defects Investigation
Preliminary Evaluation PE11-007: Haldex Brake Chamber Spring Failures
- Closed
NHTSA's Office of Defects Investigation opened Preliminary Evaluation PE11-007 on March 29, 2011 and closed it on September 23, 2011. NHTSA's investigations file lists the 2007 Sterling L-Line for it.
Updated daily from NHTSA's investigations file
Key facts
- NHTSA number
- PE11-007 (also written PE11007)
- Investigation type
- Preliminary Evaluation The first stage of most defect investigations: NHTSA's Office of Defects Investigation gathers basic information about a possible safety defect, including from the manufacturer.
- Status
- Closed September 23, 2011
- Opened
- Closed
- Vehicle or equipment manufacturer
- FREIGHTLINER LLC
- Component
- Parking Brake — Driveline — Air — Chamber
- Vehicles and equipment
- 2007 Sterling L-Line
A recall appears here only when NHTSA's investigations file links one to the investigation; NHTSA's summary or record can name others.
NHTSA's summary
As NHTSA's Office of Defects Investigation wrote it for Preliminary Evaluation PE11-007.
ODI opened this preliminary evaluation based on a fleet report that it had experienced multiple wheel-end fires.
The fleet believed this was due to the power spring fracturing and subsequently puncturing the diaphragm resulting in an air loss causing the brakes to drag.
A vehicle driver suffered smoke inhalation during one of the fires suspected to have been caused by the alleged defect.
Another injury was sustained by a mechanic when he attempted to remove the brake chamber with a broken power spring.
The brake chamber sprung from its mounting bracket and struck the mechanic in the face, causing multiple lacerations.
Brake chambers have a limited life span and are subject to wear out.
However, the failures identified by the fleet are much earlier than expected and may not exhibit discernible failure symptoms.
ODI initiated testing at the Vehicle Research and Test Center (VRTC) to determine the cause of the spring failure and to better understand any warning signs that may be present.
VRTC's testing is ongoing as is Haldex's inspection of failed chambers returned from the fleet.
This PE has been upgraded to an Engineering Analysis (EA11-011) to further evaluate the cause of the fires and assess the scope, frequency, and safety consequences of the alleged defect.
Vehicles and equipment listed for this investigation
NHTSA's investigations file lists these vehicles and equipment for Preliminary Evaluation PE11-007. A listed model year means only that an investigation names it; it says nothing about any particular vehicle. Model years with a try.vin recall page link to that page's NHTSA investigations section.
Sterling
Sterling L-Line
What an NHTSA investigation is
NHTSA's Office of Defects Investigation (ODI) looks into possible safety defects in vehicles and equipment, often after owner complaints. An investigation usually starts as a Preliminary Evaluation, or as a Recall Query when it concerns whether an existing recall covers the right vehicles or fixes the problem, and ODI can upgrade it to a more detailed Engineering Analysis. A Defect Petition asks NHTSA to open an investigation, and Audit and Equipment Queries are administrative investigations into whether companies complied with federal vehicle safety requirements, such as reporting, recall and certification rules.
An open investigation is not a finding that a safety defect exists, and NHTSA can close one without a recall.
To see whether a specific vehicle has an open recall, enter its VIN at nhtsa.gov/recalls.
Free VIN check: decode a VIN to see its year, make and model.
Sources
NHTSA's investigation record for PE11-007
Investigation details come from NHTSA's investigations file, which try.vin imports once a day. The investigation types are described from the U.S. Department of Transportation Inspector General's May 2023 report on NHTSA's Office of Defects Investigation, NHTSA's petition rules (49 CFR Parts 552 and 557) and NHTSA's Office of Defects Investigation procedures. How try.vin reads NHTSA investigations.