There’s no shortage of reasons for invalidating a warranty. Trump them all with proper PM and get your claim honored

 Once trucks are out the door, things happen that truck makers can’t control. That’s their argument when they deny warranty claims, and it holds legal water. That means buyers need to practice proper operation and maintenance. With newer trucks, that takes extra attention.

Changing fuel filters in a timely manner and using only those that meet factory specs is increasingly critical in preventing injector failure. When caused by dirty fuel, the failure would not be repaired under warranty.

“Many owner-operators just take their vehicle into a quick lube periodically for an oil change and figure they’re good to go,” says Michael Donnelley, service manager at MHL Kenworth in Little Rock, Ark. In reality, he adds, many warranty-related items you need to pay attention to aren’t covered in a quick oil change environment.

Basic preventive maintenance

“In the past five years, a lot of hoses, wiring, and piping, as well as new devices, have been added to meet the latest emission standards,” Donnelley says. “All these items need to be checked.” You need to keep wiring and hoses from contacting each other and the major components or you could easily experience a failure. This is an area of neglect that’s not warranted.

When a leak causes the lube level to drop below rear axle gears, they begin to run dry. Friction can make short work of the teeth on a pinion gear, not to mention all the bearings. Maintaining fluid level is the owner’s responsibility.

Another classic failure is assuming that by keeping antifreeze/water proportions correct you have adequately maintained your antifreeze, Donnelley says. “But you may have let the diesel coolant additives, which need to be continuously replenished, get out of balance. You then discover exhaust pressure in the radiator, take the truck in, and are told the cylinder liners are pitted. If that results from improperly maintained coolant, it’s not warranted.”