2015 3.5 131k. I have a confusing shutter coming from the truck at seemingly low rpm , with a high gear. Usually 4th gear , with speeds under 35 around 1100-1400 RPM. When I notice the shutter , I ran a mode 6 and shows 3-4 misfire on 3 of 6 cylinders. However when I don’t notice it for a drive , there are no misfires… anyone have any ideas . I couldn’t manage to get a video.

thanks in advance

 

First thing is to inspect the Plugs for excessive Gap and condition.
After that, and no improvement, the Coils may need to be replaced for a fault with shorted internal turns that has lowered the max voltage output under open EGR light throttle conditions that are very Lean at that time and require more coil reserve voltage that it can supply...
Testing coils with a meter will not detect this fault.
Because it come and goes, no code will be set.
Your Mode 6 is the source history of cylinder misfires.
There is a long chain of events description about how this all come about.
I just wrote about it but not doing it over again here but to say EGR is the basic root cause of this shudder that can show up faulty coils.at the particular times in a drive cycle.
Of course there can be other mechanical issues causing misfires.
Good luck..

 

 

I can't stress enough that the TCC is locked up shortly after the vehicle begins to move and stays locked up.
There is no reason it unlocks under normal operation. even on up or down shifts. Unless the PCM concludes a valid reason to unlock during a drive cycle the driver does something out of normal.
If there is no slippage under heavy throttle why would one expect slippage under light throttle, is the question. If that is the case, there should be ccde set. That code is not a always Pcm Ccde.
Good luck.

 

Shudder, shutters is what goes on house windows to keep the rain out.