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Greg Stirling
User Rank
Platinum
Weak Springs Cause Power Steering Problems
Greg Stirling   8/15/2011 2:06:21 PM
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Problems like this seem to permeate the manufacturing industry.  A company saving a few cents or dollars on a substandard cost reduced component which affects the function of the whole system - in this case a car.  I am sure whoever buys this car would be happy to spend another $2.00 to have one that is reliable.

There is a commodity in design engineering I call CS.  Collectivly, some companies have it and some don't.  Some engineers have it but management won't listen. Some companies have it, but have to hire outside contractors to provide CS.

By the way, CS = Common Sense

TJ McDermott
User Rank
Blogger
Re: Weak Springs Cause Power Steering Problems
TJ McDermott   8/15/2011 10:08:08 PM
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We have ourselves to blame for this race to the bottom.  The big-box business model is the lowest cost products, regardless of quality or service provided.  The big-box business model is SUCCESSFUL; how many independent, local, small-town hardware stores are still around?  The small town hardware stores arguably had better, personal service, might have had higher quality products, but the cost was higher as well.

Airlines have raced each other to the bottom as well.  There's not a single airline that offers a hot meal as part of the ticket anymore.  Most don't even offer hot meals!  Quality of service was sacrificed at the altar of low cost.

Many people will claim they will pay higher prices for better quality, but the market proves this is not the case.

Beth Stackpole
User Rank
Blogger
Re: Weak Springs Cause Power Steering Problems
Beth Stackpole   8/16/2011 7:49:50 AM
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@Greg Stirling: Tempering the almighty drive to roll out low-cost products with CS engineering expertise is definitely becoming a difficult balancing act for many engineering organizations. Mr. Horton is lucky that his background and skill set let him attack the steering problems head-on--most average car buyers are not as fortunate. I say take to the Twittersphere and spread the tale of caution and the potential fix--I'd be hardpressed to think Chevy won't be listening!

philipp10
User Rank
Gold
Electric power assist is scary
philipp10   8/16/2011 9:53:29 AM
NO RATINGS

The idea of electric assist power steering is scary to me.  Last week, the battery on my RAV4 lost one cell.  My wife called and I gave her a jump.  I then drove the car to work, planning on replacing the battery after work.  What I found was, as long as the revs on the engine were up, all was fine.  However, at one point, as I was exiting the freeway, the revs dropped and apparently the voltage to the power steering dropped. When the power steering kicked out, I almost ran off the exit ramp.  Very dangerous. This will at some point cause a serious accident.

DougM21
User Rank
Silver
Re: Weak Springs Cause Power Steering Problems
DougM21   8/16/2011 10:06:37 AM
NO RATINGS
There is another possible reason the original brush springs were low tension.  The following is speculation--I have no direct involvement with the electric power steering on this car.  Steering systems are very sensitive to friction, even small amounts of friction can make steering unpleasant--for example, not return promptly to center when released.  Adding a gear drive and motor to the steering column adds new sources of friction/stiction in the most sensitive place--close to the steering wheel.  I'll speculate that an attempt (perhaps misguided, in terms of the service history) was made to reduce the motor brush friction to the bare minimum in an effort to control the overall system friction. 

If friction was an original engineering concern, perhaps a brushless motor, and/or a direct drive motor (low RPM torque motor) would have been a better solution?

 

OLD_CURMUDGEON
User Rank
Platinum
Weak Springs Cause Power Steering Problems, etal!
OLD_CURMUDGEON   8/16/2011 10:20:10 AM
NO RATINGS
While almost every article that appears in this column relates to poor "engineering", I would suggest that MORE people who experience these situations take the time to contact the various gov't oversite agencies to formally complain.  That is the ONLY way that manufacturers and/or distributors are going to get the message.  This is especially true for the automotive industry.  This article is a prime example for such an occurrence.  The family involved should have NOT wasted their efforts to contact CHEVROLET, instead they should have contacted the NHTSA, highlighted all the facts, and then waited for a response.  IF, in fact, an internet search showed several thousand entries from other owners experiencing the same malfunction, that would have been sufficient "ammunition" to generate interest at the agency.  Contacting Consumer Protection Agencies in local state gov'ts may also offer some relief, since the dealership which sold the vehicle may have to answer to a gov't agent, a burden they'd rather avoid!

 

Sport
User Rank
Silver
Re: Weak Springs Cause Power Steering Problems
Sport   8/16/2011 10:45:31 AM
NO RATINGS
Inferior quality is one issue.  Even worse is Chevy's apparant willingness to deny the problem and take care of their customers.  This is one reason so many of their customers now buy Toyotas.  I'm sure it's expensive to correct this problem.  I'm inclined to think that they have gambled that it's cheaper to loose customers and or fight it in court when the time comes.

As it happens, I'm in the market for a new vehicle.  I was considering a new small Chevy as a town car.  This article has convinced me that this is a bad idea.

JG
User Rank
Iron
Weak springs
JG   8/16/2011 10:47:49 AM
NO RATINGS
Where did this person do his research at?  The Cobalt has never made any recommended lists that I know of.  Did he forget GM went bankrupt.  Thank God, 180,000 trouble free miles ago, I bought a Honda.  If he had researched the Civic or Accord we would not be having this discussion.  Oh, by the way my Accord was build in Marysville Ohio. 

Bill G
User Rank
Silver
Re: Weak Springs Cause Power Steering Problems
Bill G   8/16/2011 11:05:00 AM
NO RATINGS
Amazing stories.  When I heard of electric power assist years ago, I thought "great idea - no more fluid leaks, hoses, engine-driven belts", but looks like the implementation fell short.  I second the brushless DC motors idea.  Seems wise for a motor in continual use where brushes would wear significantly, though costs are higher.

Where do they come up with $3500 for a replacement assembly, and no individual parts sold?  Can GM spell "extortion"?  Do you think their field testing predicted brushes would fail every 45K miles?  I drive several 60's cars and parts are so cheap I keep a backup for most everything on the shelf.

Re safety, I assume they designed the electric assist with something like an over-running clutch or slip clutch (aka garage door opener).  Otherwise, a jammed motor or gear could lock up the steering, which is the worst thing.  Even if one only loses the assist, that is enough to cause some people to scream and just let go of the wheel (my wife).  In traditional hydraulic systems, that happens whenever the engine cuts off, whereas electric assist continues as long as the battery is good, which seems more reliable.

I lost the assist in a hydraulic system recently when the plastic pulley cracked, which also drained the battery (alternator slipped on serpentine belt).  I only noticed when I exited the freeway, with strong effort on the wheel.  The problem is you only notice the lost assist when you need it most.

Charles Murray
User Rank
Blogger
Shameful response by Chevy dealerships
Charles Murray   8/16/2011 11:21:44 AM
NO RATINGS
Compliments to Mr. Horton for tracking down the problem. Chevrolet's response, as explained here, is shameful, especially considering the potentially dangerous effects of this problem. I also agree with "Old Curmudgeon" below, who suggests that the victims of this kind of shoddy design should make a point of contacting appropriate government agencies.

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