Reefer drivers put more miles on their tires than average, every day drivers. Hauling billions of cargo pounds over billions of road-miles annually, professional drivers understand the importance of truck tire maintenance.
Required before and after every trip, inspections cover hundreds of potential details. Knowing what to look for in a healthy tire is a skill that comes only by doing inspections, but a list of basic checkpoints can help keep the details straight.
When to inspect:
At the start and finish of a workday—whether they are part of or in addition to the DVIR—tire inspections guarantee that the tractor and trailer are safe for long roads and heavy loads. More than a requirement, the habit of always evaluating the health of a truck’s tires will keep fuel usage down and help keep safety records pristine.
What to inspect:
Tires | Rubber
- Check for embedded objects in the tread—always remove foreign objects, no matter how small.
- Check for cuts, abrasions and impacts—wear and tear is expected, but does not normally include pitting, lacerations, or exposed steel belting.
- Check for objects wedged between the duals and remove them immediately.
- Inspect for loose or missing lug nuts—check for cracked wheel around the bolt hole circles as well as the hand holes
- Wheels that have been bent or damaged by curbing need to be checked for alignment.
- Inspect for loose or missing valve caps.
- Always discharge a small amount of air before replacing valve cap.
- Use metal flow thru stem caps and install correctly.
6 Point Valve Stem Inspection:
- Inspect for visible damage to the valve stem—bent, cracked, or pinched stems should be marked for immediate repair.
- Inspect the retainer nut threads—ensure that they are not stripped or cross- threaded.
- Inspect the retainer nut washer—ensure that it is not bent.
- Inspect the valve stem—ensure that it has no more than one (1) bend in it.
- Inspect the valve core threads—ensure that they are not stripped or cross-threaded.
- Inspect the valve cap threads—ensure that they are not stripped or cross-threaded.
Regular, non-repair tire maintenance is as simple as checking tread depth and air pressure.
Tire tread depth is checked as a normal part of scheduled vehicle maintenance. But if a tire is showing signs of wear, check it.
- Steer tires should have more than 6/32nds of an inch of tread remaining.
- Drive tires should have more than 4/32nds of an inch of tread remaining.
- Trailer tires should have more than 4/32nds of an inch of tread remaining.
Tread wear can be checked with a tire tread depth gauge, but if one isn’t available, a common U.S. penny can be used instead. Here’s how:
- Spin the penny so that Abe Lincoln’s head is facing down.
- Put his head into the space between the bands of tire tread at the place to be measured.
- If Abe’s entire head, hair included, is still visible above the tread, the tire has 2/32nds of an inch of tread remaining—or less.
- If Abe’s hair is not showing, but his forehead is, the tire has 4/32nds of an inch of tread remaining.
- If Abe’s hair and forehead are completely visible, from the top of his head to the bottom of his brow, the tire has 6/32nds of an inch of tread remaining.
Tires should show wear evenly. If one part of the tire seems to be wearing more than another, it could be a sign of improper inflation, wheel misalignment, or something more serious. When checking tread, it is important to check tires in multiple locations so that tread wear can be averaged over the whole tire. At TWT Refrigerated Services we recommend the following procedure:
- Divide the tire into four (4) quadrants.
- Look for the area in each quadrant that has the least amount of tread.
- Measure tire tread depth in these four (4) different areas of the tire.
- Add the four (4) measurements together and divide them by four (4)—this will give you the average tread depth of the tire.
Properly inflated tires maximize traction and fuel efficiency. Tires that are under pressure flex more, creating unnecessary heat and roll-resistance, which decreases fuel efficiency.
Using a tire pressure gauge, ensure that all tires are inflated to 100 psi. All tires; whether steer, drive, or trailer; are considered flat at 80 psi. And don’t forget to consider temperature:
- It takes five (5) degrees change in ambient temperature to change the air pressure in a tire by one (1) pound.
- Road temperature tires may be as much as fifteen (15) PSI higher than normal.
- Never bleed air from road temperature tires unless they are fifteen (15) pounds over the cold set pressure.
If road temperature tires are over pressure, give them a couple of hours. It takes at least two (2) hours for road temperature tires to cool.
Inspection and maintenance are the front-line tools in a professional truck driver’s safety arsenal. Driving long hours and endless miles can make the repetitive tasks of inspecting and evaluating tires seem overdone. But pros know this—tires are, literally, the only thing between the truck and the road.
Be a professional, and come home safe.