Sometimes, it’s the little things that make a good program better, even great. However, these little things can just as easily haunt you and even create disabling problems that can be elusive to diagnose and difficult to correct.
We tire people tend to focus on the big issues of proper tire selection, application and maintenance, with inflation pressure checks dominating service recommendations. These deserve top billing in all fleet tire programs. The reality is that basic issues and smaller considerations are both important.
Tire inspections: Although most new vehicles arrive with tires properly mounted and undamaged, all should be inspected before they are placed in service. A quick check of the GG ring (a molded circumferential ring in the tire sidewall) just above the rim flange will confirm the tire is mounted concentrically onto the rim. Improper, or lack of, mounting lube is the most common cause of problems here. It’s also prudent to check visually the entire tread circumference for any distorted or spongy areas. Contact with petroleum, overheating from chassis dynamometer testing, and overinflation/high-speed damage during delivery, are potential causes of problems. Cuts, snags and tear damage also can be quickly spotted by visual checks.
On/off storage: Unmounted tires should be kept indoors, or at least in a shaded area that’s dry, clean and away from any ozone sources ie. electric motors. They should be racked vertically or stacked in a way that avoids deformation of the tread area. Avoid pipe stacking tires more than eight high if they are stored horizontally. Tires mounted on vehicles should be relieved of loading or rotated periodically to avoid localized tread and sidewall deflection for extended times. Exposure to sunlight should be minimized by covering the tires or parking trucks in an east-west direction, so the tires are not susceptible to lengthy sun exposure. In all cases, contact with any petroleum products (including asphalt) should be avoided. The interior of all unmounted tires should be checked for dirt or other debris prior to mounting. The use of filtered valve cores is recommended to avoid trapping foreign material in the critical valve-sealing area.
Cleaning tires: Truck tires, once mounted, can be cleaned for cosmetic reasons, although most manufacturers agree that dirt doesn’t adversely affect performance. Soap and water is preferred. Harsh chemicals, especially petroleum based, should be avoided. Normal weathering and resistance to airborne chemicals are addressed by anti-oxidants and anti-ozone additives in modern sidewall and tread compounds. Tire dressings and chemical protectants are generally unnecessary. Mild steam cleaning is acceptable, but high temperatures and pressures, such as those often used for degreasing mechanical components, must be avoided. Tires can actually be burned or punctured by some steam cleaning.
Emergency repairs: Any puncture repairs should be made according to accepted industry practices. Consult tiremaker databooks, RMA recommended practices and/or tire repair producer recommendations. In basic terms, a proper repair consists of a plug in the puncture opening, combined with a patch in the tire interior. All emergency over-the-road repairs made by unknown vendors and all rope-type repairs should be checked and corrected by dismounting, inspecting and properly repairing the tire as soon as possible. Aerosol sealants containing petroleum or propellants should never be used. If they have been used, remove them as soon as possible.
Hidden tire/wheel damage: Some damage may not be visually apparent. Detection requires dismounting and careful inspection. Two events trigger most of these cases, namely wrecks or axle-end overheating due to brake or bearing problems. Tire beads burned from overheating brakes can lose their structural function and must be scrapped. Steel wheels can become bent, distorted or otherwise damaged, and alloy wheels can be distorted from excessive heat, especially in the critical bead-seating area. Thorough tire and wheel inspections, using criteria obtained from component suppliers, should be a mandatory part of collision repair and brake/bearing overheat repairs.
Training programs offered by tire and wheel manufacturers provide more information on these topics. Also, the Technology and Maintenance Council has several publications designed to educate tire servicing personnel in diagnosing and addressing many of these important tire and wheel conditions.