D13 and with i shift, vibration using stage 3 engine brake.

When was last overhead performed ?

 

Was it doing this before the overhead?

Check driveline for slop too..worn carrier, sloppy pinions, etc

 

I read the manual cover to cover. They don't address the engine brake but I pretty much have it down. 1,2,3 and max if you pull it down manually? I don't have eco shift thankfully, but on the stalk there is 0+ and B-. Is this for manual shifting? Haven't trued it yet.

 

Only truck with I Shift transmission have the engine brake stack with the letter B, the B position is spring return, when you active it to that position the transmission TECU select the lower gear available to keep the engine at the maximum Rpm under engine brake to maximize the engine brake effect.
Hope my explain is clear.
Ben

 

About the severe engine vibration using engine brake at position 3, that problem is under investigation for now.
Ben

 

Nop you are wrong.. d13 in manuel have same shake. Make sure on doing tuneup on time.

 

Sir,you are right the truck with manual transmission have the same engine brake vibration problem in position 3 but my post was to explain what is the function of the letter B on the engine brake switch in the cab.
Ben

 

Its the engine brake pistons. Have them removed and theirs heads locktited and tightened back down. I had this problem on my truck. Rochester did exactly what i just said and the vibration is gone.

 

Glad I’m not the only one having this issue. Vibration kept getting worse, shop ran overhead and it went away for a few weeks. Vibration started coming back, shop said #1 exhaust valve was out of adjustment again and performed another overhead, truck vibrates and runs worse than it ever has.