While we spend a lot of time talking about tires for the tractor, far too often we neglect one of the other most important aspects of the rubber on the road: trailer tires. While many fleets opt to buy new tires, others are okay with letting their old drive and steer tires find their way to the back where the trailer can see them to the end of their life.
Still, do trailers really need to end up being the tire’s graveyard? The tires used in these applications are very often neglected and rarely undergo any sort of proactive maintenance. If you imagine fleets operating in the truckload sector, it’s not hard to imagine a tire going six months or longer without anyone looking at it.
Another complicating factor is that tires are often stolen from trailers left in drop yards. In some cases, a thief can get a tire off of the rim in less than 30 seconds. It may sound crazy, but it is absolutely true. All one needs to do is take off the valve stem, let some of the air out and then punch in the sidewall. As the air escapes, they can easily get the tire off of the rim.
Making Use of Your Tires
For some, this is reason enough to leave the worn out old drive and steer tires on the trailer. After all, why increase changes of theft with a nice shiny new pair of tires on the trailer?
Thought of from another perspective, the gains you enjoy from increased customer service and truck driver satisfaction may be enough to offset a few lost tires, if a theft even happens. So how should you proceed?
For many a fleet manager, the conventional wisdom is to simply retread a steer or drive tire once. After it has been used in the driver position, then it is usually retreaded again and then put onto the trailer.
In the truckload sector you can run three to one trailer to tractor ratios, which means many tires will come in as low as 40,000 miles a year in use. In this situations, a high quality, deep rubber tire should work for you just fine.
Others hold the view that letting the tires run down as low as they can, thus reducing rolling resistance, is the better way to go. But are they taking road hazard protection into account? Today’s tire service call, on average can run a fleet over a grand with a new tire. There would have to be a significant gain in fuel savings to justify the expense for that service call.
You may also run the risk of irritating your truck driver if he or she ends up with an angry customer at the other end of the run. Today’s big shippers likely won’t even bother to consider a bid from a carrier who isn’t sitting at 98 percent on time performance or better. Are you sure you want to lose out on that potential business because you made a bad bet on a well-used, worn out tire for the trailer position.
When to Pull
The Department of Transportation says that steer tires should be pulled at 4/32-inch tread depth remaining. For drive and trailer tires 2/32-inch is the regulation. More responsible industry recommendations would likely counsel going with 6/32 or 7/32, as opposed to what the DOT mandates.
One way you can manage the movement is to pull steer or drive position tires even earlier than that and rotate them back to the trailer where they can finish out their tread life. But one does also have to consider application.
In regional or city driving situations, nails and other road debris is much more prevalent, so pulling the tires early and retreading them will ensure the tire’s casing integrity doesn’t get compromised further on down the road.
There are other more specific applications that you must consider, which we will cover in Part II of our series. Join us back here in a couple days to get the final answer on trailer tires.