usermel

The last post was short but effective. Never thought of it that way!!! L.G.N.M

Mike_TX

First, thanks for all the good wishes, guys.

As for the cause, I can only tell you what they told me. I'm not saying I buy their story, but here it is: According to them, there is a set of robots that assemble these engines. In late 2007/early 2008, one of the robots was found to be out of adjustment, such that when it installed the spring, it scraped it and caused a "score" mark on it. That small score mark created a weak point that can cause a failure of the spring after thousands of cycles.

By the time they discovered the adjustment problem, a large number of engines had been assembled and put into cars, which had been shipped out over the world. It was not known if it would be a problem or not, nor when it might result in a failure, so Lexus had to deal with it when/if a spring failed. IOW, on a case-by-case basis. It wasn't practical to recall a ton of engines just because a spring "might" someday fail.

Now, I would hope that they are building a picture of the problem as these springs actually fail ... a sort of failure matrix that will tell them how likely failure is and when it might happen. That would, I hope, eventually lead to a recall and replacement ... or at least a warranty extension for this part for affected cars.

One last comment: Cars are getting to be so sophisticated and so complex that I think we're going to have to accept some loss of reliability. You simply can't continue to cram more and more tech into a machine without expecting some of it to go kaboom. I'm not talking about springs here, since those are fairly low-tech, but our cars have so much high-tech in them nowadays that something will almost certainly break from time to time.

It's kind of an odd consequence of progress ... as our cars get more sophisticated, we get to enjoy more bells and whistles, but we also slip backwards a bit in terms of overall reliability.

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Johnny

That's a highly plausible and logical explanation. Springs are basically energy banks; when pre-loaded, they in fact store energy and release it when required. As a mechanical engineer, metallurgical questions were common and dealt with on a regular basis. Hardness, durability, strength or heat treatment in this case, alter materials and improve the life (cycles) of any given part, in essence making it analytically predictable. Any small and sometimes imperceptible flaws, whether accidental or systemic will cause stress risers, and loads will concentrate stresses in these areas leading to a reduced MTBF (mean time between failure), and ultimately premature and sometimes unpredictable sudden failure at those points. I'm quite surprised and pleased they admitted this, so it's a testament to Toyota's open relationship with their customers. Kudos to them...

jlawr

Mike, would you be willing to ask you dealership at what VIN number the "spring problem" was fixed on the assembly line?

I intend to keep my Nov. 2008 LS 460 past 70k miles. I'd like to feel reassured my car was manufactured AFTER the robot re-alignment was corrected. I'd dread having to fix this issue out-of-warranty.

Thanx.

Mike_TX

Joel, I asked this already, thinking maybe I could clue Club Lexus in on a VIN sequence of vehicles involved. They basically told me they don't know. I figure Lexus knows at the corporate level, at least roughly what "batch" of engines was involved, but they don't seem to be anxious to advertise it.

In fairness, I suppose there are potential legal considerations involved, not to mention a lot of expense, if they started a "panic".

I will say this - my car is a 2008 and was manufactured in November of 2007, too ...

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TNLS600hL

Hey Burnaby, I was wondering if you had your wind noise issued fixed at the dealer. I'm still skeptical about bringing my 600 into the dealer to have them fix. I don't want them to screw it up more than it is already. I only notice a little wind noise but it can be ignored, overall still love the car! Please let me know!

daryll40

A 2008 with 70K! Now THAT is some SERIOUS driving!

Craig B

He didn't say he had 70K. He said, he wants to keep his car past 70K...

Craig

daryll40

I stand corrected! Thank you!