This PI was superseded to include Full Size Trucks and Utilities. Please discard PIT3516C.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
An unusual vibration may be felt and heard at very low RPM, especially during parking lot maneuvers or driving at lower speeds and making a gradual left or right turn. A rattle may also be heard from under the vehicle that can be felt in the floor as the engine is started due to Powertrain movement. If equipped, this may be more pronounced when AFM (Active Fuel Management) is active.
This may be due to stones and debris being trapped in the transmission mount as shown below, which may transmit the noise/vibration into the body.
Example of a 2008 Silverado Shown Here
If SI diagnosis does not isolate the cause of this concern, remove the transmission mount and clean the debris out of the mount. Then install a 5.5" (14cm) section of 0.75" (19mm) heater hose into the cavity of the transmission mount to prevent debris from entering the mount as shown below, reinstall the mount, and re-evaluate the concern.
Notice: There should be no need to replace the mount when this issue is encountered.
Example of a 2008 Silverado Shown Here.
This bulletin is being revised to apply only to vehicles equipped with V8 engines and remove GEN3 engines. Please discard Corporate Bulletin Number 07-06-05-001E (Section 06 -- Engine/Propulsion System).
Some customers may comment on a popping/snapping noise from underneath the vehicle at idle or immediately after the vehicle is shut off. Some popping/snapping noise from the exhaust system during cool down is a normal condition. The noise may be intermittent depending on the outside temperature and or temperature of the exhaust system at the time of testing.
Some customers may also comment on a buzz noise coming from the muffler during vehicle operation.
As the exhaust system cools, the muffler shell and muffler internals contract at different rates. Some popping/snapping noise from the exhaust system during cool down is a normal condition.
If the muffler heat shield straps are loose, the heat shield may be free to buzz.
DO NOT REPLACE THE EXHAUST SYSTEM COMPONENTS.
This condition is normal to the muffler design and does not indicate poor quality or part failure.
Confirm the origin of the buzz by shimming (use metal shims) the straps tight and rerunning the vehicle. If the buzz concern is gone, then it is caused by the loose shield. Using the following procedure, install new straps to secure the heat shield to the muffler.
Tighten Tighten the strap screw to 4 N·m (35 lb in).
Strap, Exhaust Muffler Heat Shield
For vehicles repaired for a muffler buzz, use the following labor operation:
Strap, Muffler Heat Shield - Replace
*This is a unique labor operation number for bulletin use only. It will not be published in the Labor Time Guide.
This PI was superseded to update the repair information. Please discard PIT4859.
Some owners may comment of an exhaust leak or noise. This concern could be caused by an unseated pipe to pipe mid joint connection, as shown below.
To correct this concern, replace the band clamp and push the pipes together while tightening the clamp bolt. The pipe flares must be seated while tightening the clamp. After clamp is installed it does not need to be perpendicular to the pipe. It is acceptable to have a pipe to pipe or clamp angle. Confirm that the clamp edges (both sides and all the way around the clamp) are seated on the pipe, as show below.
Cross-line warranty allows GM and Saturn Service Agents to perform warranty repairs on:
First and foremost, one of the benefits of cross-line warranty is the ability to perform repairs for customers who are significantly inconvenienced. Service Agents should determine if:
Cross-line warranty can be performed for used vehicles.
Partial wind-down dealers can perform warranty service beyond their wind-down date on the brands they will no longer represent until the October 2010 expiration of the current Dealer Sales & Service Agreement.
Participation in cross-line warranty is voluntary. GM Service Agents and Saturn retailers are prohibited from promoting or advertising cross-line warranty repairs. Any violation of this could result in audit, Service Agent charge back or termination of cross-line capability. Repairs performed outside of the warranty are not eligible for cross-line warranty and require wholesale authorization.
This bulletin is being revised to add the 2007 and 2008 (New Body Style) model years, update the warranty information and add information for installing exhaust dampeners. Please discard Corporate Bulletin Number 02-06-05-003F (Section 06 -- Engine/Propulsion System).
Some customers may comment on a moan or vibration noise at low vehicle speeds 40-64 km (25-40 mph) or between(NNN) NNN-NNNNRPM under load.
Exhaust system resonance may be transmitted through the powertrain mounts into the body causing this condition.
Caution: Personal injury or burns may occur when working on a hot exhaust system, let the exhaust system cool off prior to performing the repair.
An exhaust system flex pipe kit is available to correct this condition. If diagnosis leads to this condition, install the applicable exhaust system flex pipe kit listed below using the following procedure. Refer to the Parts Information for kit applications and usage.
Important: This fix and the kit part numbers are specific to vehicle frame type. A Level 3 frame was introduced interim 2000 model year (approximately January 2000). With a Level 3 frame, the transmission crossmember was moved forward of its previous location. Pre-Level 3 frames will require the installation of additional components to correct the condition.
These models require the installation of a flex coupling. The flex coupling has adapter sleeves for the installation of U-bolt clamps. This procedure uses the U-bolt clamps, but the preferred installation method is to weld the flex coupler to the exhaust pipe.
Tighten Tighten the U-bolt clamps to 30 N·m (22 lb ft).
If the exhaust vibration or moan is still present, order two exhaust dampeners, P/N 10199232, and proceed to Installation of Exhaust Dampeners, If Necessary in this bulletin.
Tip The two dampeners should be installed close to each other on the exhaust pipe, but the dampeners should not touch together.
These models will require the installation of a flex coupler, two Y-pipe support brace rods w/integral U-bolt clamp assemblies on the LH and RH sides of the transmission rear mount and new transmission mount studs and nuts. The Y-pipe support braces are used in combination with the flex coupler to reduce exhaust moan.
If the exhaust vibration or moan is still present, order two exhaust dampeners, P/N 10199232, and proceed to Installation of Exhaust Dampeners, If Necessary in this bulletin.
Exhaust System Parts Package
1999-2000 2WD Models Built Prior to 1/00
Exhaust Muffler Vibration Dampener Assembly
That has to be a bit of relief knowing that it has been isolated to the exhaust system, knowing it's not something safety related. As for AFM operation, there is a whole list of enable and disable criteria for AFM operation. Everything from engine temp, RPM, transmission gear, throttle position, engine load, etc......, all factor into AFM operation. There really is no set time or RPM range this happens in. When engine load is high it will be in V8 mode, and when load is low (like at cruise) V4 mode. I am also a little sketchy on the display. I think AFM is more active than the display indicates. AFM operation is virtually seamless, meaning it's hard to detect the change to and from V4 mode. As far as your rubber mounting question, if the dealer will not check the exhaust for you then any shop should be able to do this for you. Obviously you will have to pay for the services you recieve, but I am sure your aware of this. You are just trying to make sure the exhaust system is not touching the frame or body anywhere and that the rubber mounts are in good shape and positioned to allow for movement to isolate vibration. If your exhaust already has a flex joint there is no need to replace it. I am sure it's functioning as designed. If the joint is factory there is no alignment that can be done to this joint, as it is likely welded into the exhaust. Adding mass to the exhaust system is a trial and error process, moving and repositioning the weight untill the exhaust is tuned to help reduce the resonance. If your dealer is not willing to do this you may try the exhaust shop. The bulletin has the part numbers listed for the weight, and you (or the exhaust shop) can order these from any dealer parts department. Unfortunately GM Techniacl Assistance is only avliable to dealer employees. In order to cal you have to have the vehicle, an open repair order, and a few other things. The phone number I gave you for GMC customer service is where you could call. They will not have technical data and are more geared to assist you the owner, but none the less it's avliable to you. This thread will continue to remain open as long we continue to post to it, it will not close because you accept the answer. Thank you for your compliments and thank you for using Just Answer.
Was reviewng all avliable service bulletins for the 2009 Yukon and ran accross a few that indicate some noise being heard when the vehicle is in 4wd or Auto modes. I think we already covered this but just make sure you are driving in 2Hi mode unless road conditions require 4wd. There have been cases of vehicles in 4Hi causing a noise/vibration. Just thought I would pass that along to you as well. And I don't think your vehicle is a 3/4 ton or 2500, but a very similar concern noted here in this bulletin:
#PIT4953: Rattle Or Buzz Type Noise From Underbody Of Vehicle At Light Throttle - (Nov 4, 2009)
Some customers may comment on a rattle or buzz type noise coming from the underbody, exhaust, or engine compartment on light tip-in throttle at approximately 30-40 MPH. The condition is most often seen when the vehicle is warm and has been running for 5 minutes or more.
The concern may be caused by a loose connector joint for the center baffle tube inside of the exhaust muffler. To isolate the concern, warm vehicle up by driving approximately 5 miles. Pull up parallel to a wall and roll down side windows. While in drive, apply the brake and raise engine speed to 1600-1800 RPM. The rattle or buzz type noise should be present in the exhaust muffler if this condition exists and can be isolated with chassis ears or a stethoscope.
If the noise is isolated to the exhaust muffler, the muffler pipe assembly will need to be replaced.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
Sorry I missed you last night, it was a late night for me. Again I am shocked by the lack of this dealer to want to fix this for you. Appalled does not even begin to describe it. As far as the bulletin goes I can only speculate on what it may be. It's a good bet though that they may have been instructed to do this by GM. The damper they are refering to I beleive is the weight/damper that we spoke of earlier and that you have the bulletin about. If by chance this is an internal unpublished bulletin from GM Technical assistance, then there is no copy to print and see. Usually when I have encountered an unpulished bulletin they only give you a bulletin number to refrence, then instruct you as to the repair. However GM service bulletins are not "privileged", there is a federal law that in a nut shell requires this information to be released to he public. This way the independent repair facilities have adequite information for diagnosis and repair. Your contact with GM Customer Service is really who I would be concentrating your effort to. If it were me I would also tell the Customer Service rep that you once agin have been treated the way you have and that you no longer trust them to perform ANY work on your vehicle. Ask where an altrenate site could be. Dealers like that deserve to feel the rath of any hammer that will fall on them. I am sorry I usually don't engage in down talking anyone, but dealers like that give the rest of us good ones a bad name. Let me know what you find out from Customer Service.
Just an update -- maybe you know -- can't figure this out.
By accident today I performed a test on the car.
I was driving and accidentally put the car into TOW mode.
The noise/vibration stopped -- I simply had engine noise -- plus at 60 mph, straight run, within 2 minutes, the car went into V4 mode.
Can you explain this?
Remember, the car doesn't seem to get inot V4 mode on light load.
Just curious what you think.
Glad to talk to you.
Yes -- the noise/vibration is changing...it is louder as I put on miles!
You said some time ago -- it could be a combination of the Trans, AFM and Exhaust some time ago. I guess you could be proven right!
On a light load driving for 12.5 miles, the car never went into V4 mode. All I get is the vibration and loud washing maching noise. It overpowers the engine. Like a diesel.
At what point at cruise control should my car have switched to V4 mode?
Tomorrow the car goes into the dealer for the damper. BUT, the GM customer service rep surprised me yesterday with a call for a follow-up which I thought was good and when I told her about this, she documented it and said she would tell the dealer.
So I guess I'll know something by the end of the week to inform you.
Are we your most interesting case?
AFM has quite a few enable criteria, so it's hard to tell definitvely when it will activate. I have provided a rough illustratition below for your refrence. I also provided the disable crieria, so if AFM is active and any of the disable criteria are met the system will go back to 8 cyl mode.
Cylinder deactivation may be inhibited for many reasons including the following:
I have seen many intresting things throughout my career. This does rank roght up there though. Keep me in the loop.
Took the car into the dealership today.
The service advisor Mike was surprised to see me and asked me why was I there.
I reminded him that the GM rep Jennie informed me to come in as the damper was at the dealership with the clamp.
He knew nothing about it. He called the part dept and they informed him they were ready for me.
I had to wait 45 minutes before they could bring the car around to test drive!
I explained I was here for the possible AFM problem. The service advisor Mike asked what that even was???!!!??? No joke.
He then insisted no paperwork was needed but I insisted paperwork was required as per the GM rep to have a service report completed. I questioned his wording on the report but nothing changed.
He then called the owner Coleen and said 'this guy has papers hear about an AFM problem and I don't know anything about this.' I gave him some copies of literature on the subject matter on the patent and functionality of AFM.
This service advisor and 2 techs then took the car on a ride with me in the back seat as advised by the GM rep. One of the service techs Jeff was driving the car and the other service tech Dave was in the back seat with me. After 10 minutes, the 2 service techs (one driving and one in the back seat with me) admitted they heard a "groan" and/or a "moan" and felt a "vibration" -- 'like going uphill'. The one tech even put his hand on the backseat floor.
The service advisor Mike still heard nothing and gave looks to the others and seemed most agitated with them.
As we were driving, I asked why the car never goes into V4 at 60 mph at 10 minutes cruising at a light load with no wind resistance. The tech driving responded that the car only goes into V4 mode when you coast off the gas!!!
The service manager (who knew nothing about AFM before) now agreed.
As the service tech was driving, he announced to everyone in the car that the car was at V4 mode at this time. I pointed out to him that his foot was off the gas pedal! When I told him to drive at 60 mph and lock the car into cruise control and watch the DIC and the rpms -- the car NEVER went into V4 mode and the 'groaning' was very evident. The service techs said nothing and the service advisor said it was normal.
I reminded him that a 'tone' is nothing similar to the 'excessive groaning' this car is experiencing. My other Surburbans went into V4 mode at 60 mph in cruise control giving me 21 miles per gallon energy efficiency. This car cannot.
Why would this car not go into V4 mode to save fuel? That is what it was patented for.
Now when we came back to the dealership, the service manager mentioned that the damper would go on the car. The tech Dave said that the damper and weights should eliminate some of the noise. The tech Jeff (driver) simply walked away.
The service manager once again said he still heard nothing so I responded 'remember -- 2 techs heard against 1 (you saying normal).'
I got a loan car - same engine and same transmission -- and guess what -- comfortable enjoyable ride -- no noise, no struggling of uphill, no vibration. The car went into V4 mode as expected as I drove during the day on my usual runs.
In the afternoon I got a call from the service advisor Mike who heard nothing and he said - they put the damper on and there was no change.
Now the advisor informed me that they would be contacting the Field Engineer who recommended the damper and request he show up asap.
I tried contacting the GM rep Jennie and she was not available at 5 pm when the dealership called me.
The saga continues...
I slept on all this last night and decided to call the GM customer rep first thing in the AM..
She responded with apologies for how I was treated and escalated the issue to her supervisor who got on the phone with me.
They assured me they would be calling the Field Engineer and I told them I did not want that service advisor anywhere near my car again.
For anybody to tell me that the AMF works when coasting -- even she knew that stepping on the gas causes the V4. Every car I have ever had never had this problem.
The service manager has called my office and left message to call him back but I called the GM customer service and they told me to avoid any phone calls for 24 hours until I heard from customer service.
The supervisor was calling the dealership owner.
I liked what the customer service rep said to me -- even it is were normal, the dealership was supposed to use resources available to satisfy the customer. She even said I should not be concerned about his remarks of normal as she could understand why I did not want him near my car when he did not even know what AFM was or how it worked.
REALLY appreciate all the info you send.
Wish you were here fixing it and I am sure I would be driving my GM with enjoyment.
Will definitely keep you informed.
P.S. The loaner I have now feels and sounds just like all my other GM cars. I real joy to drive!
The service manager was leaving messages at work and home of simply "call me" for the past few days.
Then on Friday, 4 PM the GM new rep (escalated) informed me that the service manager called them and informed them that the Field Engineer was already there and tested the car and it was fine.
SO -- the GM new rep told me that would have to take the word of the Field Engineer and then also told me that the service manager said I had to pick up my car first thing Saturday AM or pay penalties with the loaner car.
I WAS FURIOUS. The other GM rep promised me that the service manager would never set foot in my car again as per my request -- and that I would be able to either speak with or at least test drive the car with the Field Engineer.
GM offered compassion but no resolution!
SO -- On Saturday early AM, I returned the loaner and went to the dealership.
The car pulled to the front for me -- but when we inquired about the paperwork -- THERE WAS NONE!
We refused to take the car without paperwork so the salesrep called the service manager on the phone but came back to tell me there was no paperwork.
We refused to take back the car without paperwork.
We then had to get a loaner again.
I intend to report this to GM with the following inquires:
1. Was there really a Field Engineer?
2. WHEN was he there testing my car?
3. WHAT testing did he perform?
I want paperwork to document what was done!
By the way, I read that there is a 'GM memo' or TSB regarding the noise/vibration issue. Is that what you gave me already?
Any other recommendations?
p.s. What is Diablosport Predator and Cortex ? Was told by others that it is the fix I need.
I want GM to make good on this car.
I am hoping the muffler and weights if put on my car would help.
BUT what if it doesn't?
GM confirmed to pick up the car today as we complained to them that the car had no paperwork.
Ironically, the paperwork was now done but indicating how the service manager Mike F. was behind getting the escalation and the engineer.
Whatever. I made a complaint to GM that I requested a drive with the Field Engineer and instead that service manager drove with him.
The big news is that remember when I told you how Tow Mode make the car fell right? Well now with the damper and clamp -- the car is worse than ever even with the Tow Mode. I used to have peace at least in the Tow Mode and now I cannot tolerate.
GM said there is nothing more they can do since the Field Engineer found normal drive.
I will make a complaint to GM that the damper and clamp is worse. Maybe these dealership techs put in on wrong? I don't know.
Can it come off again?
I'll talk to GM tomorrow.
We did talk with GM just today and they did indicate they were calling back as a courtesy for feedback.
The GM rep (escalated) who first told us we could never drive with the Field Engineer -- now listened to our complaint about the installation of the damper and clamp & informed us that the Field Engineer was coming back 1st week of December for a one-on-one test drive!
GM also honored our Cross Warranty request (thank you) and I as the main driver, I am meeting with the Field Engineer next Tuesday at 9 AM at another dealership (which they recommended and with whom I would prefer to go to!)
I am glad the damper can come off if needed -- or even moved if needed.
The problem is that this noise just never leaves the cabin and I now cannot drive in TOW MODE which at least gave me some relief that I could listen to engine noise.
This is wasting so much time but we are being persistent and my wife tells me to stay calm and not be overbearing as you also said.
I never hated AFM before, but with this car (as good as it looks) it is just not enjoyable to drive.
If the ECM does need calibration, can't GM do it, and if so how?
How can you tell that the ECM is out of calibration? How can the Field Engineer know for sure it is the AFM? I want to know what I should be saying to the Field Engineer?
By the way, is it true what one mechanic told me that Canada is shipped GM cars without AFM?
Well, you have kept me going with some hope and much information.
Next week, hopefully the Field Engineer will find there is a problem and know how to fix it.
I am not sure you received my last response on 11/14 -- good news regarding GM allowing me to test drive with the Field Engineer.
Just simply want to know if there is any advice when I meet with the Field Engineer this Tuesday!
This should all be hopefully resolved this Tuesday!
You have been a great help -- better than anticipated.
Just wanted to end with giving you good news.
Please read my previous reply and answer the best you can as you always have and let me know.
Hope you had a great Thanksgiving.
Waiting to hear your answer to my reply!
Did you get my response on 11/24?
FYI -- the Field Sales rep from GM called today and said he will be driving with me and the Field Engineer also.
We are on for tomorrow 9 AM sharp!
Hope this is good new.
Any feedback before I go???
Just wanted to update you with today's events.
I drove the car with the GM Field Engineer Dan and the GM Operations Manager.
They let me take the car for 32 miles on the open highways -- on my usual routes for my business -- and guess what!!! THEY HEARD IT! They both looked around as I drove and acknowledged they felt the car suffering as if 'going up a mountain' and said it was internal and that whatever was causing those sounds was 'out of acceptable category'.
The Engineer had the car hooked up to some computer and at one point, whatever he did, he asked if I heard anything now and I indicated no! But I noticed that the rpms on the car were up. When he turned off that button on the computer, he even said 'now you hear the noise again' and I agreed.
THIS WAS THE SAME GUY that the other dealership took for a ride and he heard nothing with them! Wonder how they drove it for those simple 6 miles they took the car according to the report.
Then I asked him to drive the car back -- and he agreed!
While he was driving with me, he was listening and trying to determine where the sounds were being generated from. His face looked puzzled but determined. At one point, I asked him if his foot was vibrating, and he said the floorboard definitely was.
When we came out of the car, he looked around the car, told me he 'heard the noise' and the operations manager agreed -- and promised 'I am going to go back and try to find out what it is'.
When we came back to the new dealership, the Engineer took another vehicle out and we drove and all admitted that despite a 2009 with 5.3 liter -- no noise! The Engineer investigated and found that this vehicle had no AFM!
The Operations Manager said they would 'go back to the drawing board and see what can be done' to make my car just like the other car. The Engineer also informed me that so much time and effort could be costly to GM if the car cannot be fixed -- and when I inquired about a replacement car, the Operations Mgr said that GM would make that decision down the road. They just told me to sit tight and they would investigate and then contact me as this is a 'puzzler'.
What do you think!
I did what you said -- I was not overbearing, polite but firm and persistent. I hope you don't mind but I used your line: "I know you don't build the car -- but it's in your best interest to fix the car!"
This dealership also was pleasant and cooperative and indicated I could bring the vehicle here for whatever GM recommended!
Turns out -- my brother (another die heart GM guy like me) buys all his trucks and services them from this dealership. They treated me really nice.
The 2 GM guys were really nice too!
So what about that computer? What did he do to get rid of the noise? Is it a calibration or did he override the AFM? As a mechanic, do you know if the Engineer can download from the car without AFM and calibrate into my car?
Anyway, so far I am glad I listened to you and not buy any devices or go to any outside sources. I am glad these 2 GM specialist heard the sounds and agreed it needed to be addressed.
GM customer service later called me and confirmed that the 2 GM reps admitted they 'heard the noise' and that the 'Engineer is going to investigate' as to what can be done to 'make the car more comfortable.'
Do you want to know the final outcome? or do you want me to let you go know! You have been such a big help. Wish you were here.
Let me know!
I am glad to hear they have finally taken the time to duplicate the concern. Now they can diagnose the source of the concern and hopefully find a solution for you. I suspect what the engineer had was a diagnostic scan tool that was plugged into the vehicle allowing him to see various data to help diagnose the source. What he likely did was disable the AFM or some other component with the scan tool while you were driving. All GM dealers have this type of tool, a technician who can interpret and use the tool is a completely separate issue. As far as different engine calibrations to disable AFM - I am not sure what GM can do. I suppose there is some legal issue to deal wit has well concerning emissions and what the vehicle was certified for when it was produced. If anybody has the capability of doing that your engineer does. I am also glad to hear the new dealer has a better attitude towards customers. I think I would advise sticking with them for all of your repairs and maintenance.
Keep me informed as to how everything turns out. Hopefully they find a solution for you soon.
Have a quick question.
Can you help me on this one?
IF the NOISE and Vibrations and now sluggish ride (new development) is NOT due to the AFM needing to be calibrated or whatever...
How can I be sure it is NOT the AFM?
Is there a switch or button or cut off to the device to rule it out? (and I don't mean the over the internet devices people buy as I agree with you on that).
I am getting to think it is more of a piston problem or hole in the muffler?
Another mechanic I asked today said it could be the cylinder and told me to ask 'your friend' (which is you).
The noise is getting louder and the ride is getting more and more sluggish.
We have not heard from the GM Field Engineer.
Aren't we entitled to a report from the test drive?
We left a message and asked the Customer Service rep who coordinated the test drive for the test drive report and/or for the test drive Diagnostic Scan Report - but they have not responded to us.
Aren't we entitled to it?
Why would AFM cause such problems if disengaged since I have so many problems with it engaged? Remember, I said the Engineer did something during the scanning and the noise/vibrations suddenly disappeared and the Engineer asked me if I noticed the difference and I agreed I did.
I would really like to have that report! How do I go about getting it?
I am not sure what kind of report will be available. I would say your best course of action is to remain again persistent but not overbearing with GM Customer Assistance. They will have direct contact with the needed resources to handle your problem from here. I really wish I had more to give you but I am afraid you have all the information I have available to me. Hopefully you have had contact with them since the last post here, and are closer to a resolution. I wish you and your family a safe and happy holiday season.
Please don't forget to ACCEPT your answer if you feel I have helped you. I do not get credit for the guidance I have provided unless you do. Thank You for using Just Answer.
In case you did not figure it out, GM came back with the verbal response that the case was closed for customer support and that the noise and vibrations were all due to AFM and all normal.
Yet, that day of the test drive -- they agreed it was a problem and was able to turn it off?!?!? And they have no report to forward to me to find out what they did!
I refused to accept that and continued to contact GM customer support as new developments of smell of burning and rattling rumbling began in the car.
Finally, the GM operations manager agreed we could take the car to a dealer of our choice. -- YOU already told us that cross warranty was a reality!
We finally found an engine expert who found the burning smell to be residual rubber which wore off and is now gone. He also found that the rattling rumbling was due to inproper installation at the factory -- a factory defect in the installation of the heat shield above the catalytic converter -- never tightened which the first dealership never found!
If you recall -- the GM bulletins you sent us -- that was ONE OF THEM!!! Finally someone knew what to look for and knew how to fix that!
The last problem is now the original roaring struggling noise of going uphill.
BUT -- the new dealership we are dealing with are willing to review the problem and the engine expert indicated that the damper placed by the original dealership was placed incorrectly on the vehicle.
You will not believe where it is -- in the front of the car on the top of the exhaust pipe ... instead of where the GM bulletin indicated -- of course, another ONE YOU GAVE US!
P.S. there is supposed to be 2 dampers and a strap and only 1 damper was put on.
They will correct this problem hopefully -- I have an appointment next week.
THE FINAL QUESTION I would like to ask is this:
Since the exhaust noise is right underneath the break pedal and going towards the door -- why would the bulletin indicate the dampers (2) and strap should have been put on in the rear anyway? Does this make sense? -- Is this true?
Let me know your final thoughts and/or comments.
And Merry Christmas and Happy Holidays to you and your family --
and the next correspondence will be our last!
Thanks for all your invaluable input. Still wish you were here!
Hope you get this.
You have been such an invaluable asset of information for us. Thank you for everything.
You are definitely a die-hard GM man and everything you said has been straight forward and honest and correct.
ALL the info you gave has proven to be accurate and true and we cannot thank you enough for giving us a peace of mind as well as all the facts we needed. We just had to get others to simply follow.
We are very disappointed that GM is not standing behind its car as it should -- but at least we are now with a user friendly dealer. And just to let you know, the engine expert we found is another die-hard GM man (Nascar Earnhardt all the way).
2 out of our 3 car problems have been resolved -- and we will remain persistent and persevere until the final (the original) problem is also resolved.
Thank you for all the info on the cross warranty, the heat shield, the damper, the exhaust, the AFM, etc etc etc.
We are accepting at this point so that you can get your bonus for all you have done for us -- (short of being here to actually fix the car!). IF you don't get your bonus of $100.00, please contact us at our store email address: XXXXX@XXXXXX.XXX. Feel free to contact us any time. We have been very pleased knowing you were there for us.
We are sincerely XXXXX XXXXX you -- you are what GM should always be -- reliable, dependable, knowledgeable, dedicated and committed to customer satisfaction.
John and Angela