I took my car in for a warranty check for the notorious piston slap on my
3.1 Century. They told me that the piston slap was "normal" and let them know if it gets louder and to bring it in. When's that? When the warranty expires out? So they can make more money on it? There is a TSB on it and I think it should be repaired. If its normal why have TSB on it.
They have TSBs on tons of stuff, in some cases they're there to update procedures. Or they're also there to put in guidelines for when to do services (as in your case). Look at the Dex-Cool thing, there's a TSB out that says to flush the coolant system if the heater doesn't blow hot air/the temp guage doesn't rise or something along those lines (it's been awhile since I've looked at it) for certain vehicles. It may not happen to all vehicles but for the ones that it does happen to the dealership knows what to do.
I also remember GM said that the piston slap isn't going to damage the engine or anything (I'm not quite sure if I believe that or not..one part says "yea...sure...they make the engine" then another part is like "it's making a noise that it's not supposed to make"). How bad is it? Does it go away after it warms up?
"Joseph A. Zupko" wrote
How long does the noise last? If it only lasts for a few minutes..you are out of luck. They won't replace the pistons unless the noise is there after about 10 minutes of running.
Newsflash: TSB's do not mean "warranty" or that the dealership is forced to perform the repair.
Ian
My 2001 Malibu had piston slap.
It was so bad that 2 of the cylinder walls were gouged by the slapping and they had to install a new engine. This all happened within the first 46,000 kms.
Brad
I'm going through the "motions" with the GM rep now. He saw my 2002 Venture a couple of weeks ago and said it wasn't bad enough yet and that was passed-on to me by the dealer. I demanded to have him look at it while I was present, the dealership said no and I said I will be calling GM Customer Care. Guess who I'm meeting this Thursday? Yup! I'm one ticked-off EX customer. Check out
Steve
"Brad Clarke" wrote in message news: snipped-for-privacy@4ax.com...
The contrast to how Honda is handling problems with it's recent automatic transmissions is instructive. A whole range of Honda vehicles has had it's transmission warranty extended to 100,000 miles unilaterally by Honda. A friend of ours recently had the tranny fail for no good reason at 49,000 miles on her out of warranty 2000 Odyssey. Honda replaced it free of charge and provided a loaner car for the couple of days it took.
Any company can have problems. What separates the customer centric companies from the rest is how they deal with the problem.
Our '02 Silhouette had the dreaded intake manifold gasket failure at 47,000 miles. Luckily it had the GM extended warranty because GM threw the extra warranty in for free to move Oldsmobiles. Otherwise we surely would have been stuck paying to repair something which is clearly an engineering/manufacturing screw up.
GM continues to manage it's warranty costs by pissing off customers who have dealt in good faith.
Not smart.
John
I have had a very bad dealer experiance. But Im not going to let it stop me from buying more GM cars & trucks. I can introduce you to people who have had worse treatment from outher automarkers and their dealers.
Any one in the infromation age, who does not check out a vehicals known pitt-falls before purchase, especially when known like your problem.. Is asking for trouble.
The Montana is basically the same Van, same motor. Caddilacs owners buy gadget mobiles, look at all those 4-6-8 junkers.
When you go out and just buy with no reasurch, you shouldn't get out a soap box and hallar about it. Not to mention if your nice, and level headed, not to mention reasonible you will get alot further.
Charles
Ummmm.....I KNOW they're basically the same van. Not trying to sound "off" here but what does that have to do with it? GM lost a sale because of what they are refusing to do, stand behind their products. The intent of my posting was to "inform" and tell him there are MANY people who are experiencing this same problem. I was not looking for criticism in this "information" age. MAYBE we don't all have the Internet when we purchase goods. Also, being nice got me as far as I have SO far but now the time has come to be somewhat more determined. There are LOTS of ways to accomplish things but, as you can see by the number of complaints, it is taking more. Believe me, I'm VERY level headed. In closing, this is not the forum for personal criticism so let us stop it here. The guy asked for help so I told him what I am going through with this same problem. You would be very surprised how many people do not know what that sound under their hood is until you tell them. Have you looked at the site?
Take Care.
"Charles Bendig" wrote in message news:%7Hlc.63882$ snipped-for-privacy@fe2.columbus.rr.com...
DOCUMENTATION BY INDUSTRY EXPERTS ON THE SUBJECT OF PISTON SLAP:
Dr. Victor Wong/MIT (Massachusetts Institute of Technology), is one expert who states otherwise:
Piston Slap. Few technologies have received more engineering attention than the internal combustion engine. Yet engine designers continue to be troubled by a phenomenon known as "piston slap." As a piston moves up and down inside its cylinder it also shifts from side to side, bumping first one side and then the other--a behavior that wastes fuel, wears out engines and makes an annoying bang. A computer model developed by MIT researchers can disentangle the factors that lead to piston slap, helping engineers make design decisions that will reduce its intensity. Given a description of the operating conditions and design of an engine, the model can describe the pathway the piston follows inside the cylinder, the force with which it hits the wall, and even how its shape changes due to the impact. In parallel work, the researchers have validated the model using an operating experimental engine. The team was led by Dr. Victor Wong, a principal research scientist at MIT lecturer in the Department of Mechanical Engineering. The work was funded by Nissan Motor Company. reference:
The noise called piston slap is caused by one or more pistons having too much clearance between its side skirt and the cylinder walls. In effect, the pistons become too small and wobble in the cylinder bores. It can be cause by an engine simply wearing out (not common any more), a piston seizing because of a lack of lubrication (it runs out of oil) or it's put together wrong. This is easy to check and usually it doesn't happen to all the pistons. But there could be other causes, none of which could be caused by a "wrong" oil filter. Find out what brand oil filter your shop uses and call its service reps and tell them your story. reference: NWclassifieds/Autos- Research It: Auto Q&A
James E. Harris, proprietor of Engine Restorations in Portland, Maine also disagrees with GM's assertions regarding piston slap:
One way to check for piston slap: Remove three spark plugs, leaving number one in place. Crank the engine over until you feel the resistance of number one piston coming up on compression. Crank against compression until the piston is about half way up the cylinder. Now using the fan, rock the crankshaft back and forth and listen for a metallic knocking sound. If you hear a knock, you have piston slap and the only way out is to rebuild the engine. reference:
As the first piece of info you have there suggests, it is not simply a matter of the piston-to-bore clearance being too large (as the other paragraphs suggest). Many engines tend to do this either brand new or at pretty low mileage, and they have not all been machined/assembled incorrectly. It's inherent to the design, specifically the shape and size of the piston skirt. As manufacturers change the piston designs to try to reduce friction and improve fuel economy, this has become more of a problem.
This is also why unless there are redesigned service parts available (and sometimes even then), replacing pistons isn't likely to be a long-term fix..
What gets me is saying these people are "INDUSTRY EXPERTS". You have an MIT Professional student who probably has never even seen under the hood of a car. He thinks MIT has a computer model of the cause, big friggen deal I can use a damn piece of PVC pipe and a soda can to show you what piston slap is.
A Columnist who basically writes what others say on the subject regardless if it is correct, (that is a trustworthy source there)...
and ONE person who tells you how to check the piston - bore clearance on a cold engine. I guess nobody in the world knows what a hypereutectic piston is and why it is used in the newer vehicles and in NASCAR engines. Maybe they need to talk to the people who design and build engines about this problem. Now IF the pistons are still bouncing around when the engine is at operating temperature you might have a problem and GM might even repair that.
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.