Post Date - Mar 31, 2022
Proper tire management is crucial not only from a cost standpoint in this inflationary economic climate, but also for the general safety of our drivers. Proper tire inspection during a pre-trip will help avoid blowouts and irregular wear, resulting in less downtime and greater MPG/a smoother ride. To prevent a CSA violation, it is not enough to simply bump test the tires to check for air pressure or simply look at the tires and determine how much tread depth is remaining. It is critical to check tire air pressure with an air gauge and tread depth with a tire tread depth equipment. As a company, we are investing in flow through valve stem caps to make it easier and faster for each driver to properly check their air pressure. Please examine the information below, as well as examples of why these pre-trips are important.
- We set the steer air pressure to 120 PSI, the drives to 110 PSI, and the trailers to 100 PSI. We pull our steers at 5/32nds, our drive and trailers at 4/32nds (DOT is 4/32nds and 2/32nds).
- The bead ring should be perfectly concentric to the wheel, which means it should be the same distance from the bead ring on the tire itself on all sides of the wheel. If this is not the case, the tire will get out of round, resulting in irregular wear and a poor ride.
- There should be no more than a 5 PSI variation in air pressure and a 4/32nd difference in tread depth between neighboring tires on the same axle (drive or trailer). Mismatched tread depth or air pressure will result in choppy tires and uneven wear, resulting in blowouts/early visits to the shop to replace tires, i.e. downtime.
- If there is any metal visible on a tire due to a cut or scrape, the tire must be replaced. The metal will oxidize due to moisture in the air and rust over time, resulting in brittle metal and a blowout. Given our application and the job sites we visit, this step is critical. After leaving any jobsite location, inspect your tires for scrapes and deep cuts; it will save you time in the long run!
- Keep a look out for cap separation, particularly on trailer tires.
- With a spread axle application, the trailer's front axle tires wear the most; to help mitigate this, drivers can make wider turns when parking to reduce side to side dragging of the tires. Dragging the trailer sidewalls from side to side will cause sap separation and
- If a tire is low on air pressure (15-20 PSI below the threshold once tires are initially aired up), have it repaired first and replaced second. DO NOT CONTINUE TO AIR UP THE TIRE IN AN EFFORT TO AVOID THE SHOP. If you do this, the metal sidewall of the tire will gradually weaken owing to the greater flexing caused by lower air pressure. The metal will eventually break, resulting in a blowout. Consider what happens to a paperclip if you repeatedly bend it back and forth; it ultimately breaks into pieces.
- We are entering the summer months, and as temperatures rise, the roadways become hotter, causing tire PSI to rise. If you're checking your tires right after getting off the road, don't let the air out of them. This will result in low air pressures the subsequent drive cycle, causing the sidewall to flex more than it should. Allow the tires to cool for 30 minutes before testing the air pressure and making any necessary adjustments.
In essence, make sure your air pressures are correct (consider weather conditions), your tread depth is correct/not mismatched, and there is no physical damage to the tires. If you have any doubts regarding whether or not a tire needs to be changed, contact maintenance.