DEPARTMENT OF TRANSPORTATION
National Highway Traffic Safety Administration
Denial of Tire Defect Petitions
AGENCY: National Highway Traffic Safety Administration (NHTSA), Department of Transportation.
ACTION: Denial of petitions for an investigation into alleged defects in Firestone Steeltex tires.
SUMMARY: This notice sets forth the reasons for the denial of two petitions submitted to NHTSA under 49 U.S.C. ß 30162 by the Law Offices of Lisoni & Lisoni of Pasadena California, requesting that the agency commence a defect investigation of alleged defects in all Firestone Steeltex tires manufactured since 1995 and in those Steeltex tires installed on ambulances. After a review of the petitions and other information, NHTSA has concluded that further expenditure of the agencyís investigative resources on the issues raised by the petitions does not appear warranted. The agency accordingly has denied the petitions. The petitions are hereinafter identified as DP04-004 (All Steeltex tires) and DP04-005 (Steeltex tires on ambulances).
FOR FURTHER INFORMATION CONTACT:†
Mr. Gregory Magno,
Safety Defects Engineer, Office of Defects Investigation (ODI), NHTSA,
400 Seventh Street, SW, Washington, DC 20590.
Telephone: (202) 366-0139.
Petition Review Ė DP04-004 and DP04-005
On May 12, 2004 the Law Offices of Lisoni & Lisoni (petitioners) submitted two petitions requesting that the Office of Defects Investigation (ODI) commence an investigation of Firestone Steeltex tires pursuant to 49 U.S.C. 30162, and issue a recall order pursuant to 49 U.S.C. Sections 30118(b), 30119, and 30120. One petition pertains to all Steeltex tires manufactured since 1995 (DP04-004), and the other pertains to Steeltex tires on ambulances (DP04-005). ODI began a technical review of DP04-004 and -005 on May 26, 2004 in accordance with the provisions of 49 U.S.C. 30162. During the review, ODI:
Based on this technical review, ODI has concluded that the petitions should be denied.
Steeltex is a model name applied to the majority of light truck radial tires sold by Firestone since 1990. Over this time period, Firestone has manufactured in excess of forty million Steeltex tires in three load ranges (C, D, and E), two types (all terrain (A/T) and all season (R4S, superceded by the R4SII)), and twelve sizes at five plants. Steeltex tires have been the primary original equipment (OE) tire on many of the largest passenger vans, sport utility vehicles (SUV), pickup trucks, and "cutaways" (including motor homes (RV) and ambulances) sold in that time period. Almost three quarters of Steeltex tires produced are Load Range E (LRE) tires that may be inflated up to 80 psi and can carry between 2,500 lb and 3,400 lb per tire. More than half of Steeltex tires are concentrated in three sizes: LT225/75R16, LT245/75R16, and LT265/75R16.
Steeltex tires are light truck radial (LTR) tires comprised of two polyester body plies and two steel belts. Within the population of Steeltex tires there exist a variety of designs that include obvious differences such as tread pattern, sidewall configuration, and tire size as well as differences in internal construction such as cord configuration, cord gauge, cord angle, and mold shape. LTR tires are distinguished from passenger radial (PSR) tires by having heavier cord gauges, thicker rubber plies, deeper tread depths, and substantially higher inflation pressures. These qualities enable them to carry heavier loads and resist chipping and tearing. However, these characteristics also increase their sensitivity to usage factors such as overload, underinflation, and overspeed. This is due chiefly to the heat generated by these factors and the lesser ability of thicker, heavier tires to dissipate this heat. Heat promotes a reduction in the material properties in all radial tires.
ODI initiated its first investigation (PE00-040) of Steeltex tires on September 9, 2000. PE00-040 was closed on April 9, 2002. The primary bases for the decision to close were the fact that the tires under investigation displayed failure rates comparable to those of LTR tires sold by other major manufacturers and that many of the failures reported were influenced by the usage factors cited above. ODI also noted that the vehicle type had the largest influence on the likelihood of a tire failure causing a vehicle crash.
ODI revisited the question of Steeltex tire failures during its technical review of a petition (DP02-011) from the Law Offices of Lisoni & Lisoni in November of 2002. DP02-011 alleged that all Steeltex tires manufactured since 1990 were defective, that ODI had undercounted VOQs in its database, and that Firestone had deliberately understated its failure figures. ODI denied DP02-011 on June 16, 2003 on the basis that VOQ and Firestone figures had changed little since the closing of PE00-040 and that the petitions added relatively little new data for consideration.
The petitions under consideration here allege that all Steeltex tires manufactured since 1995 are defective and that Steeltex tires used on ambulances pose an unacceptable safety risk to Emergency Medical Service (EMS) operators. Among other things, the new petitions contain allegations that Firestone cost reduction efforts compromised Steeltex tire durability, and the petitionersí assessment from their examination of disabled Steeltex tires in Firestoneís custody.
3.0 DP04-004 Analysis (All Steeltex tires produced since 1995)
3.1 VOQs since the denial of DP02-011
During the fourteen months since the denial of DP02-011, ODI has received 294 Steeltex tire failure VOQs, approximately three-quarters of which reported tread separations. † Fourteen VOQs allege that the tire failure led to a crash, of which six involved injuries, with no deaths.
In terms of tire fitment, Class C RVs based on cutaway van chassis represent the largest share of VOQs received, with just under half of the Steeltex tire failures reported; however, none of these involved a crash or injury. RV complaints largely involved the Ford E-series dual rear wheel platform using LT225/75R16 LRE Steeltex R4S tires.
Pickup trucks accounted for a third of the VOQs and half of the remaining crash reports while Ford Excursions equipped with tires subject to Recall 04T-003 accounted for a third of the crashes, and half of the injuries. 
Excluding tires subject to Recall 04T-003, the total known Steeltex failure VOQ count now stands at 1,451; of which 908 report tread separation. Thirty-four VOQs report vehicle crashes, of which 28 led to injuries or deaths. A total of 51 injuries and 6 deaths were reported.
3.2 EWR Data
ODI began receiving EWR data from all major tire manufacturers in December of 2003. This includes data on production, adjustments, property damage claims, and death and injury claims and notices. Scrutiny of these data earlier this year contributed to Recall 04T-003.
ODIís analysis has found that, in general, Steeltex tire property damage claim rates are very close to and in many cases below the LTR class average, with a number of major LTR tire manufacturers having higher claim rates. In all cases, for each size of Steeltex tires, two or more competitors experienced higher property damage claim rates.
ODI also reviewed the death and injury claim and notice (collectively, "claim") data and found that Steeltex tires were above the industry average for injury-only LTR tire claim rates but had some of the lowest fatal LTR tire claim rates. With respect to injury claims, two major LTR tire manufacturers experienced higher rates. 
3.3 Tire analysis
To determine whether a pattern of failure modes or underlying causes existed in Steeltex tires, ODI hired Thomas M. Dodson, an expert in tire forensic analysis from a prominent tire and materials test lab,  to examine tires at Marengo. A total of 89 Steeltex tires were randomly selected from within each of three tire sizes,  half of which had been examined by the petitioners.
According to the report issued by Mr. Dodson, while tire failure modes observed at Marengo appeared similar at the macroscopic level, they were quite varied when viewed from a close-up perspective. The report also stated that the numerous different failure modes observed did not indicate the presence of a common or singular underlying cause of failure. Furthermore, the report also found that the types of conditions and/or appearances observed were consistent with the array of modes of failure typically seen in tires of comparable size and type. Usage factors such as road hazards, mounting damage, improper repairs, and overdeflection figured prominently in Mr. Dodsonís observations.
The ODI engineer who participated in Mr. Dodsonís examinations of tires at Marengo also witnessed the petitionersí examination of 74 Steeltex tires in Akron and observed many of the same contributory factors and conditions.
3.4 Firestone Data
ODI reviewed thousands of claims  received by Firestone over the last ten years. After filtering out tires subject to Recall 04T-003, misapplications, and the most obvious road hazards and flex-failures,  all Steeltex tire sizes and lines show failure rates that are lower than those observed in peer LRE tires. The four largest LRE tire sizes continue to account for 85% of claims and all but one of the nonfatal injury crashes that occurred in 2002. Tires manufactured in 1999 account for the highest number of claims and of injury crashes.
ODI also examined Firestoneís warranty adjustment data and found no signs of a defect trend overall, or in any specific tire lines and sizes.
In summary, the above information indicates that Steeltex tires overall do not stand out from their peers in terms of failure rates, and there are no indications of a defect trend.
4.0 DP04-005 Analysis (Steeltex tires on ambulances)
4.1 ODI VOQs
ODI has received over 100 VOQs relating to ambulances over the last ten years, 28 of which involve tires, four of which reported concerns with valve stem durability or accessibility, or sidewall cracks. Of the 24 VOQs that report tire failures, two involved Michelin tires. One of the Michelin complaints reported multiple sidewall failures that stopped occurring after the fleet converted their OE rubber valve stems to metal clamp-in valve stems.
The VOQs that report Steeltex tire failures involve Type I and Type III ambulances based on the Ford F-350 and E-350/-450 dual rear wheel platforms. Most of these failures occurred on the rear axle. None of the 22 VOQs allege a crash, injury, or death. Most incidents took place in 2000 and 2001, with the most recent incident occurring in August 2003.
4.2 Firestone Data
Over the last ten years, Firestone has received a total of eight claims relating to Steeltex tires on ambulances. Six of these are claims for property damage only, while the remaining two are personal injury claims involving a total of three injuries, including one death. One of the injury claims was dismissed because the injury could not be substantiated and the LT245/75R16 LRE tire involved displayed the classic flex failure mode associated with severe under-inflation, while the other claim, involving the death and a non-fatal injury, is still open.
Overall, the property damage claims are confined to Steeltex R4S/R4SII tires, mostly involving LT225/75R16 LRE tires. With the exception of a misapplied LRC tire and two failures due to extreme underinflation, failure times varied from two to five years in service.
4.3 Ford Data
Ford produced the vast majority of LTR tire-equipped ambulance platforms, totaling almost 60,000 over the last ten years. Dual rear wheel vehicles, which were predominantly fitted with Steeltex tires, account for two thirds of ambulance production, with Type III E-350/-450 cutaways accounting for almost half of overall production.
Ford informed ODI that it chooses tire fitments for ambulance package-equipped vehicles based on the tireís ability to meet speed and load requirements. It has further stated that it discourages vehicle modifiers that convert cutaways into finished ambulances from changing the OE tire fitments provided by Ford.
Ford has received sixteen tire-related complaints concerning ambulances over the last ten years, a quarter of which relate to valve stem leakage or tire misapplication. The sole reported injury crash involved a Uniroyal tire failing on the right rear position of a MY 1997 Type II ambulance in 2001. One additional crash was reported in 2002 that involved a patched tire and no injuries.
Review of the failure data reported to ODI, Firestone, and Ford indicates that Steeltex tire failures on ambulances are spread out over a significant period of time, and often involve usage factors such as misapplication, valve stem concerns (as evidenced by the complaints regarding valve stem durability and access), and road hazards.†† Additionally, analysis indicates that Steeltex tires were, until 2003, the predominant tire used in dual rear wheel ambulance applications and, thus, uniquely exposed to tire issues associated with ambulance operation.
5.0 Petition Allegations
The petitioners made numerous allegations,  which primarily restate those in DP02-011: that ODI has undercounted Steeltex VOQs; that the volume of complaints  gathered is evidence of a safety defect trend; and that the subject tires contain manufacturing and material defects. In contrast to DP02-011, the petitioners have now examined a number of failed Steeltex tires in Firestoneís custody and have characterized their findings as evidence that the tires are defective in design and manufacture.
ODI has reviewed the materials submitted in the petitions and found that they do not demonstrate the existence of a safety-related defect trend or warrant the opening of a defect investigation. The petitions allege a wide array of defects throughout the various sizes, load ranges, and designs of Steeltex tires manufactured by Firestone since 1995. These include inferior raw materials, inadequate component gauges, improper splices, improper curing, inadequate rubber-wire adhesion in the steel belts, and various other design and manufacturing deficiencies.†ODIís analysis of all of the available tire failure data does not indicate that the Steeltex tires contain a defect condition and certainly do not support the petitionerís claims of such a broad range of defects.
The petitioners did not conduct any testing or laboratory analyses to support these claims and some of the claims are in direct conflict with others. For example, the current and prior petitions allege that the Steeltex tires contain the same defect as the Wilderness A/T tires previously recalled by Firestone and identify inadequate rubber-wire adhesion, as allegedly demonstrated by "shiny brass" in the belt wire, as one of the primary causes.† Extensive lab analyses of hundreds of Wilderness A/T tires performed by ODI, Firestone, and Ford during the course of EA00-023 found good steel cord-rubber adhesion and that Wilderness A/T tire tread separations involved fatigue crack growth through the skim rubber between the two steel belts, rather than at the interface between the rubber and steel. Likewise, many of the tires examined at Marengo displayed crisp multi-level tear patterns in the skim rubber, suggesting good steel cord-rubber adhesion. The report submitted by the petitioners at the end of July contains many similar internal contradictions and scientific errors. 
The petitionersí resubmission of allegedly undercounted Steeltex VOQs contained many of the same errors highlighted in the DP02-011 denial: Fully one fifth of these complaints involved tires sold by Firestoneís competitors,  non-Steeltex Firestone tires,  contained no failure summary or description, or reported conditions that were not tire failures such as vibrations and rapid wear. In the end, somewhat more than half of the original number of complaints submitted by the petitioners alleged a Steeltex tread separation.
DP04-004 Exhibits E and F contain information concerning the petitionersí tire examinations at Marengo. While the petitioners used former Firestone employees as consultants, they applied forensic condition codes that are not used by Firestone and in many cases do not accurately describe a disabled tire condition. Many basic mistakes were made, including the misstatement of the DOT code or consumerís name in almost a third of the records.
The petitioners make numerous references to the C95 cost reduction program  conducted by Firestone in the mid 1990s as evidence of unacceptable reductions to Steeltex tire quality. † Firestone has stated that many of the recommendations cited by the petitioners were never implemented. The petitioners have attempted to link Firestoneís search for lower cost materials to a labor dispute at a carbon black supplier from which Firestone buys relatively little material. The petitioners also allege that lighter steel cords were used, reducing steel cord-rubber adhesion; yet ODI has observed signs of strong steel cord-rubber adhesion in most of the Steeltex tires that it examined. The petitioners have alleged that process times were shortened leading to undercure of Steeltex tires, and that such tires would fail early in service, but we note that failure data show that these tires generally fail well into their service lives, on average after three years of use, and halfway through their tread life.
DP04-005 alleges that Steeltex tires endanger ambulance operators and contains two references to press reports of patients dying as a result of ambulance tire failures, 41 signed statements from EMS companies, and additional contact information contained in Exhibits A and B.
ODI has found significant inconsistencies in this information. For example, one of the alleged fatal ambulance crashes involved a Type II ambulance that left the road and rolled over. Closer investigation found that that there was no evidence of a pre-crash tire failure, and that the vehicle was in fact fitted with Michelin tires. Two of the complainants that filed signed statements included in DP04-005 were not EMS services and did not operate ambulances;  the vehicle crash experienced by the Kinross EMS was not caused by a tire failure;  and fully one third of the EMS services contacted by ODI did not experience a tire failure while driving. 
In determining whether to open a defect investigation into a product, ODI typically considers a number of factors, dependent upon the alleged defect and component at issue.†The decision whether to re-open an investigation into Firestone Steeltex tires was based on consideration of a number of matters identified during the course of the technical review. These considerations were discussed at length above and include such items as the number and trend of owner complaints, claims and adjustment data, the number and severity of injury claims, and evidence of a possible source and mode of failure.
Standing alone, no one factual consideration was dispositive. For example, the fact that the adjustment or property damage claims rates for Steeltex tires may have been comparable to or lower than competitor tires, was but one factor. Other information was considered as well, such as the number and severity of injury incidents associated with the tires, and the variety of failure conditions observed during ODIís tire examinations.
As noted in the denial of DP02-011, the subject Steeltex tires represent an immense and diverse population of tires that are used in the harshest LTR tire applications. The data continue to show that the rate of Steeltex tire failures is similar to that of other tires in similar uses.
The petitionersí data and VOQs show that Class C RVs, representing a relatively small segment of vehicles that use Steeltex tires, account for the largest share of recent failures, but a very small share of the crash numbers. Class C RVs are an especially severe LTR tire application because, by design, they operate very close to the tiresí rated capacities, are subject to tire pressure maintenance concerns, and accumulate mileage at a lower rate than most other vehicles equipped with LTR tires.
Additionally, the independent tire failure expert ODI retained to examine an assortment of failed Steeltex tires was unable to find evidence of any specific type or mode of failure in the tires. His examination concluded that the tires demonstrated evidence of a wide variety of failure modes, all of which were consistent with the failure modes typically seen in tires of comparable size and type, regardless of manufacturer.
With regard to ambulance applications in particular, tire examinations and interviews conducted by ODI, and surveys conducted by Firestone have uncovered evidence of significant tire maintenance concerns (many of which also apply to RVs). ODI examined 21 ambulance tires and found many of the same conditions observed at Marengo, including flex failures and unrepaired road hazards. The dual rear wheel arrangement on many ambulances often renders the inner valve stem inaccessible, making it difficult to assure that proper pressures are maintained. Up to a third of the vehicles surveyed by Firestone evidenced substantial underinflation of their tires. This is especially significant because, like RVs, ambulances operate very close to the maximum carrying capacity of their tires most of the time. 
Based on ODIís analysis of information submitted in support of the petitions, additional complaint and claims information gathered since the DP02-011 denial, and its examination of failed Steeltex tires, it is unlikely that NHTSA would issue an order for the notification and remedy of a safety-related defect in the subject tires at the conclusion of the investigations requested by the petitioners. Therefore, in view of the need to allocate and prioritize NHTSAís limited resources to best accomplish the agencyís safety mission, ODI is denying the petitions to reopen the Steeltex investigation. ODI will continue to monitor the performance of these tires for any signs of an emerging defect trend.
Authority: 49 U.S.C. 30120(e); delegations of authority at CFR 1.50 and 501.8.
Kenneth N. Weinstein
Billing Code:† 4910-59-P
 A "failed" tire is a tire that experiences a major component (e.g. tread or casing) separation or other event including rapid air-loss while driving.
 This figure does not include letters mailed to ODI at the behest of an August 4, 2004 e-mail from the petitioners to their clients. To date, ODI is aware of 27 such letters, the majority of which describe tire failures that were reported in the petition, VOQ database, or Firestone property damage claim database. All but one of these events occurred prior to 2004.
 On February 26, 2004, Firestone announced that it would recall approximately 487,000 LT265/75R16 LRD Steeltex A/T tires manufactured for OE fitment on MY 2000-2003 Ford Excursion SUVs. Firestone estimated that 297,000 of these tires were still in service at that time.
 It should be noted that no single tire manufacturer consistently ranked the highest in any of the categories described.
 Smithers Scientific Services of Akron, Ohio furnished the expert and issued a report, available in the DP04-004 public file.
 Three tire sizes account for the majority of tire production and property damage claims, and are used on potentially sensitive vehicles such as large passenger vans and ambulances: LT225/75R16, LT245/75R16, and LT265/75R16.
 In this case, the term claim refers to lawsuits and claims for both property damage and personal injury.
 Flex failure is caused by operation at extreme levels of underinflation, a condition that was identified in some tires by both ODIís expert and the petitionersí consultants.
 Allegations and supporting information were provided in three submissions: Petitions DP04-004 and DP04-005 dated May 12, 2004; a submission dated July 20, 2004 that includes video tapes of the Marengo tire inspections, copies of VOQs, and additional complaint information; and a technical report dated July 29, 2004.
 Many of these complaints allege failure modes such as flex failures, and impact breaks that are different from tread separation- the failure mode identified in the petitions. We further note that these failures can be caused by many different conditions, including usage factors.
 For example, Page 6 of the July 29, 2004 report misidentifies (tire) rubber "reversion" as the return of vulcanized rubber to its pre-cure state in the presence of high temperatures. This conflicts with established polymer science that identifies rubber reversion as a continuation of the vulcanization process, leading to a decline in its desirable physical properties. Likewise, statements made on Page 8 mischaracterize the reasons for adding natural rubber to tires as being its heat resistance relative to that of synthetic rubber.
 For example: VOQ # 748972 reported multiple tread separations on Michelin LT225/75R16 tires on a Ford E-350 RV.
 For example: VOQ # 733402 reported road hazard damage to a Wilderness A/T P265/75R16 tire on a 2000 Chevrolet Silverado.
 Information concerning C95 was submitted by the petitioners to ODI in April 2003 during ODIís technical review of DP02-011. The document submitted included a list of 153 potential cost-reduction recommendations.
 More details concerning these allegations can be found in the petitionersí July 29 technical report.
 One was a general contractor (North East Lighting Protection) and one was a state environmental agency (Florida Bureau of Environmental Response).
 A Kinross EMS representative advised that the petitioner has misquoted them. Kinross EMS has experienced two Steeltex tire failures, both attributed to valve stem extension leakage on its vehicles. The crash itself was unrelated to tire failure and occurred as a result of driving in icy conditions.
 In these instances, complainants reported valve stem leakage, vibration, bulges, and irregular wear.
 Based on these and other operational and maintenance issues identified in dual rear wheel tire applications during the course of this review, NHTSA plans to conduct outreach activities to the EMS and RV communities in an effort to improve vehicle/tire loading and tire pressure maintenance conditions.