Question - In your experience, do people who purchase "extended warranties" have to take what is offered when their vehicle is in need of repair, or may we demand replacement parts better than scrap-yard parts? - David

TOM: Even though "extended warranties" are often sold by dealers, they are basically just insurance policies, provided by a third-party insurance company.

RAY: Most of them allow you to go to just about any repair shop and have the covered work paid for directly by the insurer. I do a lot of work that gets covered by extended warranties, and in my experience, I've never dealt with an insurance company that forced me to use scrap-yard or inferior parts under such a plan. In fact, they almost always authorize brand-new parts directly from the manufacturer.

TOM: Now, you may have bought your policy from a guy named Fred, who writes extended service contracts when he's not operating his roadside fruit stand. So you need to take a good look at the policy you signed and see if it allows them to insist on used parts. If it does, then you're out of luck. But if not, you certainly can demand OEM (original equipment manufacture), after-market new parts, or at the very least, completely rebuilt parts. And I would do just that.

Question - How do you tell when a particular U-joint is bad? I have the classic squeaking noise of a bad U-joint, but my truck (a Ford F150) has three different U-joints. I tried prying each of them with a screwdriver, figuring there would be some "play" in the bad one, but I can't tell. - Roland

TOM: You really can't tell with the driveshaft still installed. You have to take it out and flex the joints, Roland. That's often the only way to tell whether a U-joint is bad.

RAY: A universal joint (U-joint) is a connector that allows the driveshaft (or anything else) to operate at a variety of different angles. And to do that, it has to flex in two different directions.

TOM: And there are two ways U-joints usually fail. Over time, the little needle bearings can wear out, in which case the joint will loosen up and get too much "slop" in it. That usually causes a high-speed vibration, or a clanking noise when you shift from Drive to Reverse.

RAY: U-Joints can also fail by seizing. That happens when water gets into the joint and displaces the grease. And then the needle bearings rust, and the joint stops moving in one or both directions.

TOM: If a joint has failed due to slop, you often CAN tell by prying at it with a screwdriver. But if it's seized, the only way to tell is by removing the driveshaft and flexing it to see if it bends smoothly in each direction.

RAY: Two other suggestions, Roland. Once you have the driveshaft out, you might as well replace all three joints. If you're doing it yourself, they only cost about $10 apiece, and it'll save you the trouble of removing the drive shaft again NEXT weekend.

TOM: And also, see if you can buy replacement joints with grease fittings. Some of them allow you to grease the joint, and that grease pushes the water out and makes the joint less likely to seize again.