Jump to content

Recommended Posts

Posted (edited)

Has anyone had a rear compressor issue with a new Yukon XL Denali? My wife and I bought the vehicle at the beginning of October 2018 and within a month the rear compressor began running excessively.  We took it into the dealership with bought it from and the service rep heard the noise but was unable to reproduce it later in the day with the technician so they sent us away with the vehicle. The noise became more and more regular so we took it to a dealership near our house and they heard it and acknowledged the problem, this lead them to replacing the rear compressor.


The change of the rear compressor didn't do the trick and the excessive running persisted, this is where the frustration really set in. The service technicians were going to run diagnostics and service the vehicle after we brought it in MLK Day. The service department manager interrupted the process and essentially tried to bully my wife into accepting the fact that this is normal behavior for a GMC Denali line vehicle. She left the dealership in tears. I called the service manager in disagreement with 1) his treatment of my wife and 2) disputing the fact this is normal. His response was the discharge the video with a bogus report emphasize the vehicle was in intended working condition. Now the Denali is sitting at another dealership while they try to replicate the issue. It occurs 30-40% of the trips we take in the vehicle and the rear compressor will run anywhere from a few seconds to 20 minutes. Has anyone else had this issue and found a resolution? I'm to the point I'm almost willing to just sell the vehicle back for a loss to be rid of it.

 

Edited by AgFan08
Video Link
Posted

Are the bags inflating properly? With it running that much I would assume the rear ride quality is terrible. I would start with checking for leaks. You should also try finding a new dealer to help you. A good Chevy or Cadillac dealer could help you too since it's under warranty and they both have systems in their respective trucks. Someone on here also mentioned contacting the GM field rep for help. Maybe they will chime in with advice. 

I would also request that the compressor be replaced again. That one seems way too loud. 

Posted

I haven't checked the bag levels but if the current dealership doesn't find the problem that is something I'll have to do.  We haven't noticed any drop in ride quality in the back (not that I've set back there often but our daughters haven't said anything), the main issue is the excessive noise which in the cabin gets loud enough to drown out music.

 

The current dealership hasn't heard it other than the first trip there with the old rear compressor, it was the dealership near our home where the service manager basically put his foot down that this is a normal noise for a Denali (there is no way that rear compressor is running normally) where they actually had heard the vehicle experiencing the issue.

 

I think I'll have to reach out to the regional GM rep but was going to wait on what the second dealership said. He's going to look up the historic work orders and see that service manager's report that the vehicle is fine which really irritates me with how he behaved. I feel like I'm up against dealerships who care more about keeping GM happy than about fixing a vehicle with an issue. Very frustrating.

Posted

It's hard to say for certain without having heard it in person, but my experience having owned a couple Yukon XL Denali's is that the compressor rarely runs, and if it does you hardly notice it when driving especially with music playing. It is even hard to notice at a stop light with no radio. Ride quality would be noticeably more firm for even front seat driver/passenger when the bags are heavily inflated.

 

The bags should always be firm if you squeeze them with your hand, but shouldn't be rock hard if you don't have a trailer/loaded cargo area. With how much your compressor runs I would expect the rear ride height to be high as well (cat in heat).   

Posted

Thanks for the information, I'll definitely check the bags when I get the vehicle back. Hopefully the current dealership identifies the issue, but the first day they had it they only took it on a 5 mile drive and didn't encounter the problem from what they told me. I'll check the bags with the technician at pickup if necessary.

Posted

The second dealership is now also trying to tell me there isn't a problem with the vehicle. This is my first GM, is this standard for how they handle warranty service issues?

Posted

Sorry you're having trouble. I've only ever heard the compressor run in mine once, and that was right after I had loaded some heavy **** in the trunk. It's definitely NOT NORMAL for the compressor to be running 20 freaking minutes at a time. I agree that you probably have a leak somewhere. This is my first GM car also, but from all that I've read around these forums, GM service departments are not the best. :rolleyes: Best of luck getting it sorted.

Posted

Appreciate it, the second dealership said they couldn't replicate it so it has to become constant before they'll do anything. Right now they are saying it's a "customer satisfaction" issue and the vehicle is fine. Pretty poor service by GM to say the least, but I've got another 30 months or 31,000 miles while it's under full warranty so there is that at least. I'm going to start compiling more footage and documenting it every time it does it, hopefully a pattern will emerge or I'll figure out some way to trigger it so I can get it fixed. The service departments I've dealt with definitely have a high burden of proof and beyond driving it, don't really want to put in much effort to figure it out.

Posted (edited)

 

On my 2012 the auto-level shocks, a similar noise turned out to be the air compressor hose had come detached from the compressor or the shock. Once I reconnected it, and got the lock spring/clamp to seat properly, it disappeared until the hole compressor went bad (over 40k miles).

Not sure about the 2018s, but just look for a plastic tube coming from the side of the rear shock. Follow that back and check each joint to see if they are tight.

You might also narrow it down by checking if the noise if coming from teh compressor. It should be mounted behind the driver side rear wheel, up on the fender. Looks like a potable air compressor wrapped ina  rubber cage/box. If that's where the noise is coming from, its either bad, or there is a loose connection and it runs until it can hold enough pressure temporarily. 

image.png.3c525f4c307a87d3fd774592c5385b6e.png

image.png.90cc95f4807f8dc7302115bd40843257.png 

Edited by ftwhite
Posted (edited)
6 hours ago, AgFan08 said:

Appreciate it, the second dealership said they couldn't replicate it so it has to become constant before they'll do anything. Right now they are saying it's a "customer satisfaction" issue and the vehicle is fine. Pretty poor service by GM to say the least, but I've got another 30 months or 31,000 miles while it's under full warranty so there is that at least. I'm going to start compiling more footage and documenting it every time it does it, hopefully a pattern will emerge or I'll figure out some way to trigger it so I can get it fixed. The service departments I've dealt with definitely have a high burden of proof and beyond driving it, don't really want to put in much effort to figure it out.

Open a claim with GM, let them know how unhappy you are, and let them know how you are being treated by the service managers (personally, if my wife came home in tears, I would have driven there and punched the service manager in the head). Don't threaten them with a demand to buy back the rig, or Lemon laws, just be firm and demand that you as a customer of GM are not happy and that you feel like you are being treated like crap! And, want your really expensive vehicle fixed so it functions normally.

Edited by JimCost2014
Posted

There's no way that can be normal noise level.  Almost as loud as the dual compressors I have in the toolbox of my truck.  Good luck with the dealership.  You can contact GMC corporate or whatever they're calling themselves and they'll open up a case.  I'm in the process of this now so I can't tell you if it will help or not, but it creates another paper trail.

Posted
On ‎1‎/‎26‎/‎2019 at 3:29 PM, ftwhite said:

 

On my 2012 the auto-level shocks, a similar noise turned out to be the air compressor hose had come detached from the compressor or the shock. Once I reconnected it, and got the lock spring/clamp to seat properly, it disappeared until the hole compressor went bad (over 40k miles).

Not sure about the 2018s, but just look for a plastic tube coming from the side of the rear shock. Follow that back and check each joint to see if they are tight.

You might also narrow it down by checking if the noise if coming from teh compressor. It should be mounted behind the driver side rear wheel, up on the fender. Looks like a potable air compressor wrapped ina  rubber cage/box. If that's where the noise is coming from, its either bad, or there is a loose connection and it runs until it can hold enough pressure temporarily. 

image.png.3c525f4c307a87d3fd774592c5385b6e.png

image.png.90cc95f4807f8dc7302115bd40843257.png 

I will definitely give this a look. I'm inclined to think it is a hosing connection issue because it is most common when the temperature is cold (below 40 degrees Fahrenheit or so). I assume that's because once materials start contracting the issue is becoming evident / amplified. A good look over the hoses will hopefully identify the issue and I can do this simple fix. Here's to hoping!

Posted
21 hours ago, JimCost2014 said:

Open a claim with GM, let them know how unhappy you are, and let them know how you are being treated by the service managers (personally, if my wife came home in tears, I would have driven there and punched the service manager in the head). Don't threaten them with a demand to buy back the rig, or Lemon laws, just be firm and demand that you as a customer of GM are not happy and that you feel like you are being treated like crap! And, want your really expensive vehicle fixed so it functions normally.

I opened a claim with GM this past Tuesday. I need to call and follow up on it. Good advice, thanks!

  • Like 1
Posted
1 minute ago, AgFan08 said:

I opened a claim with GM this past Tuesday. I need to call and follow up on it. Good advice, thanks!

You are very welcome. Be as persistent as you can. 

Posted
21 hours ago, Chevyguy85 said:

There's no way that can be normal noise level.  Almost as loud as the dual compressors I have in the toolbox of my truck.  Good luck with the dealership.  You can contact GMC corporate or whatever they're calling themselves and they'll open up a case.  I'm in the process of this now so I can't tell you if it will help or not, but it creates another paper trail.

I posted the work order along with a link to the video as a review on the dealership's website. Maybe that will get some sort of response, because as you stated and the video makes clear, that is not a normal noise level. I've never had a GM before but I'm starting to learn this is par for the course when it comes to warranty issues and getting them taken care of. Pretty much have to be persistent and in it for the long haul. Good luck with your case as well.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Latest Articles

  • Posts

    • Can it still be Assembled I?    Stribeck says that we need a certain amount of viscosity under conditions of load and velocity to prevent two surfaces of a know roughness from tearing each other asunder. And we have marketing trying to tell the masses that those two surfaced require less of that commodity due to more exact limits being placed on the same old clearances. We also know that there are limits to how hard something can before it becomes to brittle to be viable and to smooth to 'wet' the surface and that both of those conditions have been known and met since about the Second World War.    That viscosity value shook out at 10 centistokes at 212 F just under a hundred years ago.  Give this a look: [Anton Parr]     What is advertised is the Kinematic viscosity (mm2/s) or that which has been density adjusted but the value we are after is the dynamic viscosity (mPa.s) or true viscosity. You can see that this number is dependent on density thus base stock and temperature. You can also see that an SAE 30 doesn't reach that value in this example. However an SAE 30 that is at the upper end of the SAE 30 range; 12.5 cSt (mm2/s), might. 12.5 * .83 = 10.375 (mm2/s). If you could find an SAE 30 at the upper end these days.   Then there is the complication of viscosity modifiers or VII or VM, whatever you wish to call them. Polymers added to very thin base oils, perhaps 3 to 6 cP oils, that will meet the SAE *W30 spec at 'tested' shear rates and 100 C/212F  target temperature. So a polymer fortified base that is a fraction of the 10 cP requirement Stribeck insist upon.   This could be all well and good if those polymers didn't have two very problematic 'features'. They shear or loose viscosity both 1.) permanently and 2.) temporality. And they do both omitted in the advertised data with the distinct  purpose of deceiving the consumer of the actual operating state of the fluid. I've shown the example of Warren Oils COSTCO 10.91 cSt 5W30 formuation several times where the 100 C HTHS value is 6.9 cP!! That's the temporary shear down and with and SSI or shear stability index of 9.4 cSt. Note the intentional deception in using mixed units?    After a short while that 9.4 cSt oil has a viscosity corrected dynamic value of 7.8 cP. But as the SSI is still within the range of an SAE *W30 whose lower value is 9.3 cSt.    This allows them to continue to call this SAE 16 weight oil a 30 weight, the cake, and still meet the API requirements for fuel efficiency IMPROVEMENT mandated by the EPA. The eating of the cake. By the time you've worn out your motor doing the responsible thing by adhering to the warranty requirements, (the stick), you get deprived of the carrot, wear control. So sad, to bad.   So what can be done? Do I need actually say? [Anton Parr]       Even this must be monitored if the oil is on the low side and the VII an organic or you opt for a 0W40 with an even lighter base oil and more / higher MW VII. (Note the lower density of the 40 weight versus the SAE 30 mono-weight?)    There is another workaround. Temperature. An SAE *W30 run at a bulk temperature of between 180 and 195 F.    Being the belt and suspenders sort I am I do both. Run it cook and run it heavy.    In Part II I'll work the AW package. 
    • So, do I go elbow-deep on this thing or list it for sale and play dumb? Seems to "runs good."   I'm about $1200 away from having: -a rebuilt injector ($300) -a new cat ($250) -a new cat back exhaust (OE style) ($300) -a new AC compressor ($200) -AC refrigerant charge ($150)   In theory, this should rectify the obvious detracting issues from its value and operability. Cold AC with a non-squeaking AC pulley both sounds and feels good. An exhaust that isn't cut/hacked in 17 different places and doesn't vibrate on a crossmember would make it sound and feel less janky. A working cat would help the stink, and will save the earth, but *if and only if* the fuel system is working properly, which would also address the intermittent "rich" CEL.   Heard a good one... CEL for "Rich condition" means you haven't spent enough money on the truck lately, and it's letting you know.   Rebuilding the injector would seem to be the most important part. Replacing the cat would be secondary. I don't think mine is plugged or overly restricted, but it might be a little restricted? I have no good way to tell other than seat of the pants feel. I hate the smell.   The current theory is I have a rich idle problem: A bad fuel pressure regulator, or a leaking injector(s) being the highest probabilities. I already replaced the FPR but that doesn't mean its replacement isn't also bad. It was a new part from Dorman, but the packaging looked like it had been sitting on a shelf for 20 years.   This is the (single) upstream O2 sensor shown at idle. I'm getting a lot of "rich" it seems. Sometimes it stays high like that and doesn't drop down. That makes me think it's processing injector leaks or a partially stuck open injector.     Other times it looks like this. Nice oscillations between rich and lean, which is what I think it should be. Under load and at speed, the oscillations are nice and tight and uniform looking, high and low.     Fuel trims suggest the PCM is compensating pretty hard at idle to pull fuel out. But it's not enough to trip a CEL. Something about slowing to a stop: brake vaccum booster, EGR, or the EVAP purge is delayed, or there's pooled fuel in the intake again that's draining into a cylinder is enough to set the CEL. Of course, in two days of driving, it hasn't set. I was hoping to actually look at the freeze-frame data when it sets. IAT is high because it's idling on an 83 degree day here.  
    • Have considered installing a DC to DC charger in your camper to replace your isolator?  
    • Common failure.  You need to replace the fuel door housing.   The painted cover transfers over to the new housing.  To remove the old one there is 4 spots where you poke the plastic to release it.  
    • No such thing as regenerative braking on a pure ICE vehicle.     Regenerative braking is the re-capture of energy from electric motors and stores it in the battery pack.  So hybrids, PHEV and EVs have regenerative braking.     What you are seeing is the charging system changing modes is all.  Its likely entering charge mode for some sort of reason is all.  All of the charging modes will be listed below.   As for L10 vs D.  L10 turns off automatic grade braking.  L10 puts you in control of grade downshifts where in D it will automatically do it based on brake pedal position and other factors.  Otherwise L10 and D drive exactly the same aside from that one aspect.    Battery Sulfation Mode The BCM will enter this mode when the interpreted Generator output voltage is less than 13.2 V for 45 minutes. When this condition exists the BCM will enter Charge Mode for 2–3 minutes. The BCM will then determine which mode to enter depending on voltage requirements.   Charge Mode The BCM will enter Charge Mode when ever one of the following conditions are met:   Windshield wipers are ON for more than 3 s. Climate Control Voltage Boost Mode Request is true, as sensed by the HVAC control module via serial data. High speed cooling fan, rear defogger, and HVAC high speed blower operation can cause the BCM to enter the Charge Mode. The estimated battery temperature is less than 0°C (32°F). Battery State of Charge is less than 80%. Vehicle speed is greater than 145 km/h (90 mph) A current sensor malfunction exists. System voltage is determined to be below 12.56 V When any one of these conditions is met, the system will set targeted generator output voltage to a charging voltage between 13.9–15.5 V, depending on the battery state of charge and estimated battery temperature.   Fuel Economy Mode The BCM will enter Fuel Economy Mode when the estimated battery temperature is at least 0°C (32°F) but less than or equal to 80°C (176°F), the calculated battery current is less than 15 A and greater than −8 A, and the battery state-of-charge is greater than or equal to 80%. Its targeted generator output voltage is the open circuit voltage of the battery and can be between 12.5–13.1 V. When fuel economy mode is active, the generator is not charging, only maintaining open circuit battery voltage. The BCM will exit this mode and enter Charge Mode when any of the conditions described above are present.   Headlamp Mode The BCM will enter Headlamp Mode when ever the head lamps are ON (high or low beams). Voltage will be regulated between 13.9–14.5 V.   Start Up Mode When the engine is started the BCM sets a targeted generator output voltage of 14.5 V for 30 s.   Tow/Haul Mode (if applicable) Pressing the Tow/Haul Mode button located on the center stack, the vehicle system voltage is raised and the remote (non-vehicle) battery will be charged. Having the headlamps on will raise the system voltage and if the Tow/Haul button is applied it will not serve any purpose. The voltage is regulated between 13.9-14.5 V.      
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...