Semi-Trailer Loses ALL Rear Wheels: Dragged on Washington Highway

If you were driving on northbound Highway 5 near the 272nd Street on-ramp this morning, you might have seen a semi-trailer being dragged with no rear wheels.

Washington State Semi-Trailer Loses All Rear Wheels

According to Trooper Rick Johnson from the Washington State Patrol, a semi’s rear axle completely came off and left the trailer dragging behind the truck this morning on Highway 5. The axle disconnected and ended up about 10 feet from the cab of the truck, near the ditch. The falling apart semi-trailer blocked the on-ramp and a couple of lanes on the main highway. This got me wondering what could cause a big rig like this to lose its ENTIRE rear axle.

Here are some of the most common reasons why wheel loss happens according to truckinginfo.com:

1. Loose or Missing Lug Nuts - One of the biggest culprits, when wheels fall off a semi, is loose or missing lug nuts. If the nuts aren’t tightened properly or wear out over time, they can cause the wheel to come off while the truck is driving. This usually happens because the lug nuts weren't tightened to the right torque during maintenance. The truck may feel fine at first, but vibrations and stress from the road can slowly loosen the lug nuts until disaster strikes.

2. Worn Bearings - A wheel bearing is the mechanism inside the wheel hub that allows it to spin freely. They can also wear out or get damaged over time which can lead to instability in the wheel assembly or locking the wheel all together. Bearings can also overheat and cause issues even if they do not lock up completely.

3. Damaged or Rusted Axles - This accident is likely caused by some kind of issue with the axle. Axles are built to last, but over time they can become corroded or cracked, especially considering they are exposed to all the salt, moisture, and general wear and tear of winter roads. Once an axle gets damaged, it can’t hold the weight of the trailer like it should and can cause the wheels to come off entirely like we saw this morning.

4. Tire Issues - Bad tires can also cause problems. If a tire is damaged, under-inflated, or defective, it can cause stress on the axle and bearings and lead to bigger issues down the road. It might even cause the wheel to separate from the axle.

5. Excessive Heat - When friction from the road or faulty parts builds up too much heat, it can weaken important components like bearings or the axle itself. Overheated parts lose their strength which can cause them to break or fail like wheels coming off.

To avoid something like this from happening, truck drivers need to stay on top of maintenance with regular checks on tires, wheels, axles, and lug nuts. Drivers need to make sure the lug nuts are tightened to the right specs, replace worn-out parts quickly, and get professional maintenance regularly to avoid any surprises.

If you ever spot a semi-trailer that looks like it’s about to lose a wheel, don’t get too close! Stay back and call emergency services right away. Flashing your lights or using hand signals can help warn other drivers to stay alert, also.