Baytrucker

I'm only at 22000km, mostly city. I thought at first it might be carbon due to all the short trips I take with it, but everything I can pull apart (MAF, TB, etc) all look fairly clean. I called GMC directly. They said they can't open a case without a dealer. The dealer says they can't do service without approval from GMC. They are pointing fingers at each other. I've opened a case with CAMVAP to try and get something done. I hear it can be quite a process. I was hoping someone here might have some smaller things I can check in the mean time.

Hello, I have a 2017 Sierra 1500, Double Cab, 6spd, V8 5.3. My truck idles rough. My truck also shifts hard, especially on downshift. Both of these symptoms are exacerbated significantly by having the air conditioner on. The rough idle is intermittent and feels like a miss. It shakes so bad sometimes my coffee will splash out of the cup into the cup-holder. It is not consistent. It a shudder every 0.5 to 3 seconds. At warm idle, the RPM sits just below 500rpm. At park, the RPM bumps up to 600-650. The shudder can barely be felt in Park or Neutral, but is still noticeable if you are paying attention. The hard shift is a clunk, mostly noticeable at lower gears (3-2 and 2-1) when downshifting. It becomes more pronounced on longer drives. Like I said, both symptoms get 200-300% worse when the air conditioner is running and when the engine is warm. The monkeys at the dealership say that this is normal and will not attempt diagnostics or a fix. There is no other dealership nearby. I've tried cleaning the throttle body and the MAF sensor; they are pristine. I've run injector cleaner through my tank, and used higher octane good quality fuel. Oil changes every 5000km. None of this has made a difference. I am running a range unit to turn of AFM, but this device doesn't appear to effect the issue either way. I noticed this barely and intermittently when I first bought the truck, but is is getting progressively worse to the point where its hard to ignore. What else can I do here, or do I just have to live with it?

I have this issue too. I'm pretty sure anyone with a 1500 who gets their truck dirty has this issue. Its a design issue with the OEM leaf springs. Fleet truck owners don't really care if the truck makes noise, so neither does GM since fleet trucks consist of most of their sales. The only people buying GM half-tonnes privately are the poor folks (like me) who haven't figured out that GM is not even remotely close to the same company they were 15 years ago. The noise is caused by dirt getting in between your leaf springs. Its like this in all the K2 series trucks. There is no permanent solution other than to replace the springs with aftermarket. Some folks are just power-washing the springs on a regular basis. Others are sticking rubber sheets or bicycle tire inner-tube chunks between the leafs. Some have had luck with aftermarket silicone lube spray. A lot of folks just live with it. The TSB that GM has is a low-cost band-aid to get you to go away until the warranty expires. The noise will always come back. In the 2019s, GM replaced the leaf springs with springs made from composite, finally catching up to what Ford and Ram started doing in the mid 2000's. For the K2 series, they have your money already so they don't care. If it bothers you, and you can't afford aftermarket springs, something like this is your best solution.

We don't know that. GM doesn't release their repair statistics. It is absolutely fallacious to declare that these trucks are running "without issues", when there is no way of knowing if that is or isn't true. All we know is that those millions of truck owners aren't running to the forums if/when they encounter problems. We do not know whether or not they actually are having problems.

Well, dirt creates friction, which makes noise. Its probably amplified by the ricochet down the axle and frame. This truck seems VERY sensitive to harmonics. I'm guessing the friction is momentary, like when the center of gravity of the truck shifts. This sounds like a "clunk", but its actually a very short "creak". I tried adding silicone lubricant (the aerosol kind) which is the only thing that has improved the noise it so far. I did it in stages to see what spot had the biggest impact. By far, the biggest improvement was when I sprayed the section where the axle seat sits on the axle under the u-bolt. I bolts seem tight, but I don't have any way of gauging the level of torque. Even if they were loose, they were just tightened 2 weeks ago. They shouldn't be loose already. I've not tried the rubber trick yet.

Knowing GM, I would not be surprised if they advise you to adjust your driving to only go straight or turn right.

I tend to think it is quality control. GMs level of QC has taken a pretty big hit since around the time of the bailout. This is inevitably going to lead to more problems like this popping up, not just with one-off issues, but with the core design. Defects that everyone experiences. I remember reading companies like GM and Chrysler have a different engineering philosophy than most other car companies. Traditionally, when an engineer designs a vehicle, they submit a drawing to assembly, and that drawing is the final standard. If a parts manufacturer or assembly line does not conform with the drawing, then they are instructed to do-over, and match the drawing. Conversely, GM and Chrysler have a different philosophy; If a part manufacturer designs a part that isn't exactly to specification, GM and Chrysler won't necessarily send it back. If there are no immediately discernible problems with the non-spec part, they will amend the drawing to accommodate. This is just something I regurgitated from memory so take it with a grain of salt. I can't remember where I read it, but I've seen if a few times. If it was true, it sure would make a whole lot of sense, and explain why a lot of the issues we see with GM and Chrysler are shared by so many of their customers, and why the problems with other companies (Toyota's) seem to be mostly one-offs.

The oil didn't cause the issue, but it may have exacerbated it. The noise is caused by dirt between the leaf springs. Depending on what kind of oil was used, it can actually attract dirt, which will cause the noise. Only GM would design a leaf spring that you can't get dirty. Only GM would keep those leaf springs for over a decade before fixing it. The lubrication they use at the dealer is silicone based, and shouldn't attract dirt. The problem is that it washes away easy, so the noise comes back fairly quickly. I've heard that the issue is fixed in the 2019's. They moved the padding around or something. I don't know this for sure, but someone on one of the other threads has talked about it. I've also not heard of this happening on aftermarket leafs.

I'd like to know this as well.

The possibility exists. No one can tell you what the odds are. Its a fundamental flaw in the way the design of the engine, with regards to how it has been modified to meet EPA requirements. Until GM comes up with a new design, this won't change. People are saying that GM have corrected a lot of the AFM issues, but they don't seem to ever site sources for this. As far as I can tell, GM has not published a media release on this issue other than the dealer bulletin. There has been no released description as to what exactly they have done to make the lifters more reliable, so I have to assume nothing has changed since the early models. GM doesn't release their reliability or warranty statistics, so anyone saying that "fewer people are having problems with the newer models" have no basis for knowing if that is true. The manufacturer of the lifters apparently got fed up with GM sending back faulty lifters and blamed the design of the oil system. GM hasn't really responded to this in any official way. The repair basically requires a rebuild of your engine. You technically can replace just the lifter that failed, but you are better off changing out the cam too since it has likely been damaged or scored. When a metal part is scored, you have to ask where the metal shavings went. They don't just disappear. They go further into your engine. If this repair is under warranty, GM often won't investigate this far. They just replace the broken lifter and stop at that. Given how extensive the damage can be when the lifters fail, I wouldn't continue to run a truck following the failure. I'd generally consider it to be an instant trade-in.

My truck is at 19,500km. Its a 2017 sierra 1500, 5.3. As you can tell from the low mileage, I'm a city driver. I put in a range AFM disabler about two weeks ago to hopefully avoid this issue. I guess I'll never really truly know if my lifters would have failed if I hadn't blocked AFM, but I figure the odds are in my favor. In the city, I've seen less than a 0.5mpg decrease in gas mileage. One thing I have noticed is that it drives WAY better with no AFM. The transmission no longer does that schizophrenic, confused, back and forth thing it used to do, especially in large parking lots or suburban lane ways. No more hesitation when accelerating before a lane change too. The truck feels more responsive, and therefore safer. There isn't much difference in the highway. I never noticed AFM there much anyway. I plan to tune out AFM completely when my power-train warranty is up. If I ever experience a lifter failure, I'll consider a mechanical AFM delete. Everything I've read is that software AFM delete (either range or tune) is as good as it gets for preventing lifter failure ahead of time. Mechanical delete is only worth the expense if you plan to take the engine apart anyway (like if your lifters and cam have already failed).

I have a 2017 GMC 1500. I got the notice a few weeks ago that they are extending the warranty for this part, but they are not going to recall it. Seems like they learned noting from the ignition fiasco. What a surprise. I contacted transport Canada, and they actually called me back and said they are "investigating". Regulatory capture is pretty strong in Canada, so I don't expect anything to come of it. I don't care about warranty so much as I care about the idea that my brakes might suddenly change their operating characteristics without warning. I live in the pacific northwest. I can't piss without hitting a mountain. I need my brakes to work reliably. I may have to fix this out of pocket proactively. I'll just add it to the growing "GM tax" bill that continuously reminds me why I should have bought a Ford. Edit: I just checked the gm website. I stand corrected. Transport Canada just issued a recall for the part. GM Recall Number: N192217410 Transport Canada Recall Number: 19324 I called my dealership and the guy said GM doesn't have even remotely close to enough pumps to handle the recalls. They have no idea when they will be able to schedule me in.

I just bought one and plugged it into my 2017 GMC Sierra 1500, EcoTec V8 5.3. I've driven it for a day and can already see the improvement. I already knew what to expect, as I have been driving mostly in M5 for the past few weeks. I've owned the truck since new, and the subtle "hiccup" when moving into V4 at low speeds has always bothered me. The hesitation when you hit the throttle and move back to V8 also annoyed me. Mostly, it was in certain low-speed situations (parking lots, and particular intersections) where the typical conditions would cause the AFM to get confused, and in turn, cause the transmission to get confused. It would cycle back and forth between V4 and V8 at intervals of less than 30 seconds and cause the transmission to shift back and forth. Its subtle, but noticeable enough to be annoying. If you have passengers, you can see their heads snap gently back and forth as the truck has its moment of schizophrenia and the inertia of the truck shifts. With M5, and now with the Range device, most of these problems have gone away and the truck is smoother than I ever though it would be. On the highway, the AFM never bothered me. In fact at high speeds, I never noticed it. I might pull the Range out for longer trips and let AFM do its thing. I've never experienced oil consumption issues. However, I would like to tune up my idle speed a bit. It surges when the engine is warm, and idling below 500 RPM (when the engine is warm). This really annoys me. For this reason, I'll probably do a full tune once my powertrain warranty is up. I'll report back in a few months.

I contacted GM directly and asked them to contact my dealership. Not sure what will come from that. Does GM even know how to fix this issue, assuming they even acknowledge it?

I've have this issue as well. First time I took it back to the dealer and they acknowledged the noise. They said they tightened the U-bolts and put grease on and the noise was gone. As I was driving it out of the lot, the noise was still there, so I immediately drove it back with the same problem. Later that day I got a call back. I went in to get the truck and the same guy (who apparently didn't remember me) gave me the EXACT same line about tightening U-bolts and putting on grease. It was surreal. It was almost like he was reading from a script. It was verbatim word-for-word exactly what he had told me earlier. When I drove the truck away, the noise was gone, but it came back a few months later. I took the truck back to the dealer for the third time. They had it for half a day before they called me and said the noise was corrected. So when I arrived at the dealership to pick it up, they said that they couldn't reproduce the noise and that I should "keep an eye on it". I asked them why they said they had corrected the noise on the telephone, and he said he had no knowledge of that. The noise was apparent as soon as I left the parking lot. I drove it around the block and then immediately back into the dealer, when I chose to wait for a service rep to do a ride along. He refused to ride with me and said that GM wouldn't warranty the noise because it wasn't a safety issue and because the noise was within normal tolerance. Unfortunately the next closest dealer is a bit of a drive. So there you have it folks. Apparently my dealer is populated by morons, but GM won't warranty strange noises from the suspension. The frustrating thing is this is going to effect sales or trade-in prospects. I guess I'm off tot he bicycle shop for an inner-tube. Can someone post pictures of exactly what they did to make this go away?