LS in the hospital!
#77
Lexus Test Driver
Thread Starter
Mike:
I'm glad that you have your LS back safely, and hopefully forever.
Just to add to my knowledge, what caused your problem? Was it a design problem? Is there a set of conditions where the problem could be repeated?
Speaking of engines, should I let the car warm up before I drive it, especially in the cold days?
I'm glad that you have your LS back safely, and hopefully forever.
Just to add to my knowledge, what caused your problem? Was it a design problem? Is there a set of conditions where the problem could be repeated?
Speaking of engines, should I let the car warm up before I drive it, especially in the cold days?
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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#78
Pole Position
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...
Last edited by Johnny; 11-25-09 at 01:25 AM.
#79
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.
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.
#80
Lexus Test Driver
Thread Starter
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.
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.
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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#81
I'll second that. While my 460 was in the shop a bit, it was the wind noise thing, and I probably could have put up with it as I became too sensitized over time with this issue, and in my case quite frankly, it wasn't that bad. There was absolutely nothing else wrong with the car. The 600 on the other hand has been flawless; only oil and miscellaneous filter changes (DIY), and I'm now pushing 30K miles. Smooth as silk, this car...
#82
Pole Position
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.
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.
#84
Pole Position
I stand corrected! Thank you!
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