Curbside Clueless: The Curious Mystery Of The Recurring Scion xB – Toyota Noisy Clutch Release Bearing

Help!! Calling all mechanics and arm-chair mechanics!

I’m utterly stumped.Ā  In terms of reliability, my 2005 Scion Xb has in every way lived up to what it looks like: a refrigerator. Except for one utterly maddening issue, which I thought was long behind me (although I did have a few nagging doubts). Other than this one problem, it has needed absolutely nothing except for a set of tires, oil and filters. Even the original battery is still going. I will describe all the symptoms, and Toyota’s two efforts to remedy them, which have turned out to last exactly 20k miles before recurring. Which just happened again 15 minutes ago, while running an errand. Here’s the (highly detailed) chronology:

I bought it in February of 2007, from a very nice couple in Portland. It looked and drove truly like brand new given that it only had 14,200 miles. One month later, I started hearing a distinct chirping noise as I’m tooling around town. And when I put my foot on the clutch, even just a little bit, it went away.

It started out intermittently, but became increasingly more consistent. The only thing I could think of was the clutch throw-out bearing, although typically, a release bearing gets noisy when it’s depressed, not the other way. Could it be a transmission bearing; or something else?

In May of 2007, with 15,400 miles, I finally took it to my local Toyota dealer for diagnosis. They concurred with the release bearing diagnosis, and replaced the bearing, along with the whole clutch assembly along as a goodwill gesture, all under warranty. Aw shucks! They said it must have been a fluke; a random bad release bearing from a supplier. Shit happens, even at Toyota. OK; I can buy into that theory, lacking any better. Still, it seemed somehow less than 100% convincing.

20,000 miles and a bit over two years later (2009), it starts again! So what exactly are the odds of me getting two randomly-bad Toyota release bearings in a row? Any mathematicians out there? I’m increasingly convinced that there’s something endemic to the car that’s causing this.

By then, the warranty had expired, and the Toyota techs are a bit dubious, as it’s somewhat intermittent. I come back again when it’s chirping good, even in neutral. It didn’t always do it in neutral. But it did that day, right in front of their desks. They couldn’t miss it; or have a flock of birds gotten into the service department?

Without any viable explanation, they come up with the same diagnosis: another random bad release bearing. This time they only replace the release bearing, and “lube all contact points”. They give me a goodwill discount on what would have been a pricy repair bill: my share $293.01; the only repair bill to date.

The noise goes away, but the clutch has developed a bit of a shudder on take off. What’s up with that? It’s worst when cold; when warmed up it’s almost unnoticeable, although I’ve also learned how to minimize it. I never took it back.

That was at 35,125 miles, in July of 2009. Here it is almost exactly 20,000 miles (and three years) later, and it’s back. Let’s get one thing out of the way, which the Toyota techs grilled me repeatedly on: I DON”T RIDE THE CLUTCH!Ā  Sorry for the caps, but clutch-riding is a major peeve of mine; it drives me nuts when I see someone with their left foot even grazing the pedal. I lift off briskly after each shift, and once I’m in a cruising gear, my foot is firmly planted on the dead pedal. I’m obsessive about this. And no, nobody else ever drives my car, Toyota!

I just found my way to a Toyota Tech Training manual, and it confirms that release bearing noise happens when the clutch is depressed, not released.:

And it suggests that it’s transmission bearing or noise if it stops when pedal is depressed. Yet the two times Toyota diagnosed and “fixed” it, they did so by replacing the release bearing.

What does it sound like? A metallic chirping, with a decided rotational aspect (sounds like something turning is chirping). Loud enough to hear fairly readily at lower speeds with the window down. Eventually, it got loud enough to hear (slightly) with the windows closed.

I’m rather convinced that there’s something fundamentally wrong with my car that’s causing this happen every 20k miles. Maybe the transmission input shaft is out of round or off-centered? But the Toyota release bearing is self centering, and compensates for that, to an extent. Right? Or??

FWIW, the clutch is hydraulic, the pedal is self adjusting, and it “takes up” right where it should, in the center of the pedal’s arc of travel. No slippage, and full release. First gear syncro is not the hottest, sometimes a bit hesitant to slide in on a downshift from second unless the speed is very slow, or almost stopped. But then that’s been the case all along: any connection?

I need to get this diagnosed properly and fixed; once and for all. I really want to keep the car for the long haul, but I’m not ready for this every 20k miles.

OK; your turn.