What Happens If a Semi Truck Causes an Accident Due to a Blown Steer Tire?
A commercial 18-wheeler depends entirely on its two front "steer tires" to maintain control, directional stability, and lane positioning. While a blowout on one of the rear dual tires is manageable, a sudden blowout on a steer tire at 70 miles per hour is catastrophic. The immense weight of the cab instantly drops onto the rim, violently wrenching the steering wheel out of the driver's hands and forcing the 80,000-pound truck to swerve uncontrollably across multiple lanes of highway traffic.
When a steer tire blowout causes a semi-truck to plow into oncoming traffic or crush passenger cars against the median barrier, the trucking company’s defense lawyers will immediately claim it was a "sudden emergency" or an unforeseeable mechanical failure. They will argue that the blowout was an Act of God, absolving them of liability. However, modern forensic analysis proves that tire blowouts are rarely random. Understanding exactly what happens if a semi truck causes an accident due to a blown steer tire requires a deep dive into corporate maintenance negligence.
Because steer tires are so critical to safety, the Federal Motor Carrier Safety Administration (FMCSA) strictly prohibits the use of "recapped" or "retreaded" tires on the front steering axle of a commercial truck (except for certain local buses). Furthermore, steer tires must have a minimum tread depth of 4/32 of an inch. If investigators discover a retread or bald tire on the steer axle, the company is guilty of gross negligence.
Proving Maintenance Negligence
To defeat the "sudden emergency" defense, plaintiff attorneys hire specialized metallurgical and tire failure experts. These engineers examine the shredded rubber left on the highway and the remaining tire carcass attached to the wheel rim to prove the blowout was entirely preventable:
The most common cause of a blowout is running a tire with low air pressure. Under-inflation causes the sidewalls to flex excessively, generating immense heat that literally melts the steel belts inside the tire. Tire experts can identify the specific heat-signature tearing patterns on the rubber, proving the driver failed to check their tire pressure during their mandatory pre-trip inspection.
Commercial tires have a strict maximum weight rating. If the shipper loaded the cargo too far forward in the trailer, or if the driver improperly slid the fifth wheel, the steer axle will bear too much weight. Crushing a tire under thousands of pounds of illegal excess weight will eventually cause the sidewall to violently rupture.
If the truck's suspension or kingpins are worn out, the steer tires will "cup" and wear unevenly. If the motor carrier's maintenance records show the driver repeatedly complained about the truck pulling to the side, but the company refused to pay for an alignment, the company is directly liable for the resulting tire failure.
The Importance of Spoliation Letters
After a blowout, the trucking company will immediately attempt to destroy or "misplace" the shredded tire carcass to prevent plaintiffs from analyzing it. Victims must immediately hire an attorney to send a legally binding "spoliation letter" demanding the motor carrier preserve the truck, the rim, and every piece of rubber collected from the scene. If the company throws the tire away, the court can instruct the jury to assume the tire was dangerously defective.