Vibrations in park

[wyatt1672]

I purchased my truck new. Shortly after I reached over 100K I noticed a vibration while idle in park. Sonetimes the vibrations become very heavy. I have found no cause for the change in intensity i. e. cold, how long the truck idles. it seems just random. Currently at 147K miles the only major work done has been a new lift pump at 108k and a new transmission at 125k (the stock tends to burn out quicker when you bump up the horeses hehehehe) . I have had very poor results taking any of my trucks to the dealership when something needed troubleshooting. Any one have any ideas on what it is or where to start?

 

[HOBrian]

I would start with unloading the bully dog and see if that makes any difference. I would start with a stock truck first.

 

[WMoroni]

Did the vibration start before or after the new transmission?

 

[wyatt1672]

The truck had been driven over 100k with the bullydog before the vibrations started but I do set the truck back to stock when I have it worked on, I will try driving it around for a day back in stock mode to see what happens. The vibration started before the new transmission but that does not mean it did not begin with the old transmission.