2007 GMC Sierra Classic, 2500HD

[christophersond]

Not long ago, I posted a thread on a power train vibration problem I was having with my 2007 GMC Sierra Classic, 2500HD. While the vibration is always present, it noticeable (and quite loud) when I am towing my 5th wheel between 55-65 MPH. The GVWR for the truck and 5th wheel is 17,950, which is well below the rating for the truck. The dealership has been messing with the truck for over a year and a half trying to figure out the problem, and the cure. My patience grew thin, so I wrote a letter to the President & CEO of General Motors. Would you believe I actually received a response?? Today I received a phone call from the executive office of GM. They basically told me the vibration is a characteristic of the truck--live with it!! With that sort of customer service, and attitude, it is no wonder GM is going down the tubes. My truck is a 2500HD, 4WD, SRW, with a crew cab, and long bed. Take my advice, and do not buy one of these trucks..........

[conway]

I do not know if this will help but knowledge is never a bad thing. There is a GM Campaign #PIT3009J. This is a suspension vibration or frame beaming problem that manifests itself at 40-50 mph. Basically if you reference the bulletin number they will replace the rear cab mounts on crew and extended cab models. This is warranty work and does not cost anything. They have ordered the parts for my 07 classic & I have heard that it helps.

[NutNbutGMC]

I do not know if this will help but knowledge is never a bad thing. There is a GM Campaign #PIT3009J. This is a suspension vibration or frame beaming problem that manifests itself at 40-50 mph. Basically if you reference the bulletin number they will replace the rear cab mounts on crew and extended cab models. This is warranty work and does not cost anything. They have ordered the parts for my 07 classic & I have heard that it helps.Interesting and thank you. I have a 2k7 classic as well.

[mr. monte]

I have never noticed this with my '07 classic, crew cab


"knock on wood".....

[Freightliner3]

Do you know how much tongue weight you have.My son had the same problem.It turned out that his new Featherlight goose neck trailer put too much weight on the truck.In turn the drive shaft angle was out of specs. The trailer weight was 15000 empty.About 35% of that was on the the truck.He has a 2005 HD3500. GM did shim the drive shaft and put in heaver springs even though the trailer tongue weight was the real problem.He's had no issues since.

[christophersond]

Do you know how much tongue weight you have.My son had the same problem.It turned out that his new Featherlight goose neck trailer put too much weight on the truck.In turn the drive shaft angle was out of specs. The trailer weight was 15000 empty.About 35% of that was on the the truck.He has a 2005 HD3500. GM did shim the drive shaft and put in heaver springs even though the trailer tongue weight was the real problem.He's had no issues since.

The pin weight on my 5th wheel is right at 2500 lbs--truck is rated for 3000 lbs. The dealership tried a set of pinion angle shims, and it made the virbation worse. Then they tried two sets os shims, and a new drve shaft. They also checked the drive shaft angle with the 5th wheel in tow, and everything was within the specs. The GVWR for the truck and 5th wheel is 17,790 lbs (truck is rated at 22,000 lbs). My truck has two drive shafts, and I am convinced that is where the problem lies. The young mechanic was about to install some 3500HD springs when the door was slammed in my face by someone within the dealership or GM. All of a sudden it has become a characteristic of the truck--or so I'm told.... Does anyone know where I can find Campaign PIT3009J?

[rustyk]

Hopefully, this will get you started (http://www.dieselplace.com/forum/showthread.php?p=2913185)

[Runaway_Dmax]

My 08 has the same vibration when loaded most noticeable between 52 - 65 mph. More noticeable when temps are below 20*.