Dear Tom and Ray:

I am asking -- OK, begging -- you to help me figure out why my serpentine belt keeps going bad. I have a 1988 Ford Bronco with a 4.9-liter engine. The belts are supposed to last five years, but every six months or so, mine starts to squeal obnoxiously. A squirt of water in the belt grooves will momentarily silence the squeal, but not for long. The guys at the parts store know me by now as the moron who brings in a perfectly good-looking belt (with a lifetime guarantee) and exchanges it for a new one. This has been going on for three years. I suspect a misaligned pulley, but neither my mechanic nor I can find anything out of line. Any ideas? -- Phil

RAY: Well, you'd better do something, Phil, before you put those poor parts guys out of business.

TOM: Actually, at this point, they're just saving his old belts, spray-painting them and giving them back to him. So I wouldn't worry about the parts guys.

RAY: If you're sure all the pulleys are aligned properly, then it's almost certain to be a bad tensioner. The belt tensioner is a spring-loaded device that maintains the proper tension on the belt. And I suspect that yours isn't working right.

TOM: I'd just go to the Ford dealer and buy a new one. And if you don't want to mess with it yourself, have your mechanic put it in. It's not a hard job, and that should solve the problem, Phil.