I have been having some issues with my truck and wanted to see if anyone else has experienced any of the issues.
1. will idle rough at times slightly shaking truck, did'nt do when new.
2. idle will drop down below 500 rpm and then shoot right back up, somtimes doing this several times.
3. erratic idle, sounded like a loaded up 2 stroke for 30-45 seconds then idled up and ran normal.
4. not able to hear it until recently when it goes into 4 cylinder mode. can definatly hear a different tone/exhaust note when it engages. not sure if it is operating correctly.
5. chrome exhaust pipes(duals) are turning sooty black on lower bottom of pipes.
6. noticable loss of power. pulling camp trailer same load taking alot more throttle to get it up and moving and keeping it moving.

I did take it to the dealer and they scanned it and pulled up 4-5 codes with one of them being loss of communication with pcm/ecm? they noted it and said to watch it since it was not acting up at that paticular moment.

 

the soot on the tail pipes is normal I dont think anything else is.

 

WOW!!! One of my trucks is doing the exact same thing. The mechanic I know said it may be a stuck injector or bad coil. Mine will do this on and off. I think it may be the a.i.t censor cause it will only do it when the temp outside is above 85.

 

#4 is normal too. As your truck learns driving habits the MDS kicks in more often. Mine was the same way when new and gradually got more noticeable. Mufflers breaking in etc....

 

Don't know the production date on your truck and you said a tech looked at it but the LATEST and GREATEST flash update is suppose to address some of your complaints.Coils,injectors etc. SHOULD throw a code.A few posts about weird running and shifting with a ECM replacement.