So over the last few months we've been noticing a strange intermittent Vibrating/Hum noise that appears to come from the rear of the truck. It only has 76XXX miles on ...

So over the last few months we've been noticing a strange intermittent Vibrating/Hum noise that appears to come from the rear of the truck. It only has 76XXX miles on it now (3K more since we bought it 6 months ago).

Once the truck is at operating temperature, It this noise appears at 35-45 mph and when the accelerator is pressed. The sound only lasts for 1.5-2 seconds and then goes away. It's very strange and has me scratching my head. Since I am at a loss at this point and I have a warranty I made an appointment at the dealership and will drop it off after work so they can figure it out. Hopefully it's nothing too serious, but either way they can take care of it for me at this point.

I got a call back from the dealership last week and they said that they could not replicate or hear the noise that I was referring to. I explained again how it comes around and what speeds to be at, and told them to keep driving the truck. Fast forward to today, and they call me back to tell me that they finally heard it. The service advisor told me that it caught the tech off guard and he was able to replicate the noise a few more times since then. That is good news (for me!)

They had a meeting about the truck with the other techs and the foreman because of the unusual nature - and they don't believe its a driveline issue because of how intermittent it is, but they believe it is something to do with the brakes, especially the parking brakes. ANOTHER BONUS FOR ME! Since I complained about the parking brakes on the truck when we bought it. Now they will look into the rear brakes, and hopefully replace the parking brake assembly and kill 2 birds with 1 stone.

PLOT TWIST I talked to the dealership yesterday afternoon and they said they could not find anything with the brake assembly on either side. But while they were inside there looking around they found that one of the straps for the heat shield on the muffler is missing and they were able to hit the muffler in such a way to replicate the noise. They put a new strap onto the heat shield and made sure everything is tight again. They drive the truck around more and the sound did not come back for them.

I have a trip planned for the weekend and I am planning on taking this truck, so I will be able to see if the sound comes back or not. Hopefully that heat shield was the issue and was vibrating just right when the gas pedal was being pressed and the truck was under just the right load...

It's really great that they might have discovered the problem, Matt. Most dealers go into customer complaints about noises and vibrations with blinders on and generally think the customer is full of crap. They should be commended!

Yes, they have been really good with me. I always go in telling them what diagnosing that I have done, and other related items to help them out with the issue. I do that with both trucks, and both dealerships have been great towards me in this regards.

So I picked the truck up and spent some time chatting with the guys at the dealership. They love the truck over there, because of how rare it is and the work that I've done with it already. They mentioned how many people have asked about it and how it turns heads.

They also thanked me for my help with everything and being able to leave the truck for the extended period of time so they could spend time for proper diagnosis and actually be able to find the sound. After all said and done, they only charged me for an hour of diagnostic time for the whole thing. I have to say that is awesome for everything.

They showed me what they did, and the repair to the heat shield. Everything looked good, and on the drive home the truck was silent. Very thrilled - looks like it was the issue and its all fixed.

That's awesome, Matt. That kind of customer service is exceedingly rare these days.

GBSierraSLE wrote:That's awesome, Matt. That kind of customer service is exceedingly rare these days.

Yeah. One thing in life is that you get treated the same way you treat others. I came in knowing that this was a strange issue and that it was not going to be easy to find, especially with it being very intermittent and having to have everything just right to get it to vibrate/make noise. I gave them as much time as they needed (almost 2 weeks) and kept authorizing them to just drive the truck.

After everything was done, we were chatting and I commented on how easily they could have told me to buzz off with the issue, and they laughed and they said that since I actually let them work and didn't give them an unrealistic deadline to get the vehicle back, like most people they took care of me. That dealer has had a bunch of bad reviews over the years but I am clearly not giving them one. I am sure most of the bad reviews are from Karens that demanded an oil change be done in 10 minutes and then be compensated for their "lost time" since it took 15...

Figured what would be better than to get the truck nice and clean when it’s 20* outside







Can’t wait for warmer weather to get the truck out of winter mode, but gotta deal with it for now...

Picked up an oem dash vent panel with DIC buttons, from an auto wrecker in Nebraska. Now I’ll be able to unlock some more options on the DIC and gain access to more options. Just waiting for some warmer weather, since it’s been 10* outside for the past few days and plastic is very brittle and I don’t want to damage anything when I take the old panel off.