I recently purchased a 2008 Dodge Ram 2500 Mega Cab with the 6.7L Cummins. When I shift into reverse, the exhaust vibrates hard enough to shake the entire truck. I took it in to get checked by the dealership, and they told me it is because the idle rpm is set to 575 vs the normal 725. It is set this way to help with the "clunk" when shifting from reverse to park. This is also the reason why it feels like it wants to stall when it's in reverse. This sounds like a garbage excuse to me. Does anyone else have this issue? is it normal? Can I fix this by installing a programmer and setting the idle rpm in reverse higher?

 

It is normal. Mine does the exact same thing...

 

Are you sure about that? I use to own a 2007.5 mega 4x4 and it never did anything you are describing.

 

I have some exhaust vibration too. Its getting worse, but things always seem worse when its -30 and things are silly stiff.

 

Now, I know why my current exhaust is vibrating the h-e-double Kit Kat sticks out of my truck is cause my Cat is split wide open from front to back. I'm getting rid of it this weekend and putting in a test pipe.

 

What happens in reverse and the reasons for it described by the original poster are accurate and correct. Before I deleted the heavy NOX/DPF, I did not notice it much, but after doing so I raised the same questions and learned this is true. My delete pipe now amplifies the vibrations in reverse due to the dropped RPM's as compared to the heavy emmisions equipment previously. Not a big deal though to me since I know it is normal part of the trucks operation...

 

Thank you for your responses. It seems strange to me that it vibration like that would be normal for any vehicle. Seems like it would be too hard on the exhaust system, over the life of the truck, to vibrate like that. I am going to install a programmer and see if I can set the idle higher. See if that makes a difference. If the normal idle RPM in drive doesn't make the exhuast vibrate like that, setting the reverse idle RPM to the same should make the vibrations stop. In theory anyway.

 

I don't think any programmer will do that for you, but who knows... Maybe you should check to make sure all the exhaust hangers and isolators are attached. My deleted NOX/DPF had 3 hangers just for it and the delete pipe I have only uses one of them... Also, I have had the furthest isolator downstream by the muffler and tail pipe come out on me before...