Goof of the Month: A Thump, a Clunk, and Nothing More

Welcome to Goof of the Month, our monthly dip into the world of automotive cluelessness, fearing for the worst, and stories about the need for drivers and shoppers to understand their vehicle, how to maintain it, and how it works.

This month, a happy tale of a customer who feared the worst, and was pleasantly surprised when our auto repair expert, John Kennard, had a closer look at the issue that brought them in.

It all started when one of Kennard’s long-time customers rang him up with a concern about a nasty sound her minivan was making. The customer described a loud and random clunk/thump in the rear end that seemed concerning. She was worried about whether the vehicle was safe to drive.

“We’ve been servicing Colleen’s minivan, and her husband’s truck, for years now,” Kennard said. “We are a used car dealership as well as a repair shop, and both Colleen and her husband have been repeat customers for years. They live close by, and my daughter actually helps with their kid’s baseball team. Sometimes, it’s nice to have customers you see regularly, at work and elsewhere.”

Kennard told his customer to bring her minivan in.

“Often, sounds like that are something to do with the suspension,” he said. “Our pothole season started early this year, and we see a lot of vehicles making all sorts of noises. Ball joints, struts and shocks, and in some cases, bushings, are the common culprits. The roads give these parts of the vehicle a beating, and we do a lot of suspension work this time of year. I wouldn’t take your family on a road trip in a car making that sort of noise, but she was safe to bring the van in so I could have a look.”

The customer arrived the next day, and Kennard took the minivan for a test drive.

“We start diagnosing something like this by going for a test drive, so we can hear the sound for ourselves. Sometimes, it’s a guessing game, but I’ve become pretty well versed in determining the problem when I hear things for myself.”

Kennard’s test drive was a short one. After a few moments, the noise had manifested, and Kennard had a hunch – based on his years of troubleshooting unwelcome noises – as to the cause.

“In many cases, worn-out suspension parts make a clunk that sort of sounds like metal on metal – it’s a sharp, distinctive sound. Colleen’s van was making a loud noise, and I could feel it through the floor. But it was a softer sort of sound, which made me wonder if it was actually metal on metal.”

Kennard returned to the shop, and told his customer to hang tight for a few more minutes. He had a theory.

Shortly thereafter, the minivan was in the air on Kennard’s hoist, and Kennard was standing beneath its rear end. In about 15 seconds, he’d located the problem.

“I called Colleen in, to show her what the problem was. She’d been worried about the repair bill. This minivan was getting on in years, and she’d told me earlier that she had to get a few more years out of it. So far, it had been good to her family, but she was probably worried her luck was about to run out.”

But that wasn’t the case on this particular day.

With Colleen watching, Kennard pushed gently on the spare tire, which moved back and forth.

The spare tire on this minivan is mounted beneath the rear of the vehicle, suspended by a metal cable that’s attached to a winch. When required, the driver can lower the tire from its resting place, by working the winch. When the spare tire is not needed, the winch is fully retracted, and the spare tire is pulled up and out of the way. Here, it’s kept stationary by a small plastic bushing that slips snugly into the housing of the winch mechanism.

“It’s like putting the spare tire in Park, when you wind the winch up all the way,” Kennard says. “The cable retracts; and the assembly that supports the spare tire tucks up against the winch, and locks the tire into position so it can’t move around and make any noises.”

In this customer’s case, the plastic bushing had failed and largely disintegrated. “There was a piece of the bushing remaining, but most of it had split apart and fallen off.

“This spare tire was still in the correct position, but without the bushing doing its job, it wasn’t quite secure enough that it couldn’t move around a little. And when it did, the tire whacked into the nearby underside of the vehicle, causing the clunking sound.”

The fix was simple: Kennard simply removed the spare tire from the winch, cut off the end of the cable where the damaged bushing had been, and installed an aftermarket eyelet to replace it.

This part features a two-piece design that threads together. After slipping the winch cable through, the two threaded pieces of the eyelet are bolted back together, and the entire assembly locks onto the cable. A tapered edge ensures compatibility with most applications when the spare tire is retracted, and the cost of the part is about $25.

“We see this often enough,” Kennard says. “It’s always a good idea to check your spare tire winch and cable regularly, because they often get damaged by corrosion over time. Sometimes, they fall off, which is bad news. Other times, you get noises like this.”

Kennard said that the winch and cable were in good shape, so he didn’t replace them. He figures this saved his customer nearly $200.

Result? Kennard replaced the end of the winch cable with a $20 part, lubricated the spare tire winch assembly while it was accessible, checked to confirm that the new setup held the spare tire in place adequately, and sent his customer on her way.

“She was quite happy, I think,” he comments. “It’s always nice to give someone some relief. If this had been a suspension problem, her bill would have been much more. But this was a simple fix. She left with no more clunking, a secure spare tire, and was on the hook for less than $50.”