Dirty dozen

Max Kvidera | July 01, 2010

How to prevent

• Every 30,000 to 50,000 miles, when your truck’s in for service, have water drained from the fuel tanks.

• You can do it yourself by unscrewing the drain plug at the bottom of the tank. Water, which is heavier than fuel, drains first. Replace the plug when the drainage turns from clear to amber-colored.

Cooling system dysfunction

McClusky notes that half of major engine failures result from improper cooling system maintenance.

In conventional coolant, nitrites form a barrier against cavitation, manifest by holes in the wet sleeve cylinder liner in the engine block. The problem arises when nitrite levels drop too low to protect the liners. Cavitated liners allow coolant to get into the engine oil.

If you have an electrical ground fault where current runs through the engine block to find a ground, the process rapidly depletes the nitrites. Electrical problems soon follow. Eventually, you’re facing an in-frame overhaul. McClusky has seen a truck using conventional coolant break down after just 2,000 miles because an electrical problem led to cavitated liners.

The emergence of extended-life coolant has caused confusion as to how often different coolants should be checked. To avoid problems, don’t mix conventional coolant with the extended-life type.

How to prevent

• Monitor nitrite levels with coolant test strips.

• Use extended-life coolant to increase longevity and reduce maintenance frequency. It’s good for 600,000 miles, with an interval at 300,000 miles when you add an extender additive, available from major oil manufacturers.

• Pay for a coolant analysis, similar to an oil analysis. It can catch nitrite depletion that may be linked to an electrical problem.

Broken belts, clamps and hoses

Inspecting belts, hoses and clamps is especially important during extreme temperature changes, when expansion and contraction can damage them.

Abrasion, heat, oil, ozone and dramatic temperature differences can weaken belts, hoses and clamps. If these simple devices fail, you could end up on the side of the road with an overheated engine, loss of the electrical charging system or a cooling system that doesn’t work. Over time, extreme heat can deteriorate rubber compounds.

Hose leaks often start with simple chafing of hoses. “Air-conditioning system or water hoses are good examples,” says Hoyt Moore, president of Hoyt’s Truck Center. “We average two to three service calls a month with hoses with rub holes in them.”

Chafing air hoses are the latest “hot buttons” for state inspectors, Hess says. Some are writing tickets for hoses showing rub spots, even though no leak has developed, he says.

How to prevent

• Check belts for tightness and damage from heat. Look for signs of glazing on the belt’s exterior. Replace if cracked, frayed or torn.