Need Urgent Help

[hhow55]

(01-12-2017 )Danny Wrote:  Hello forum, i need your urgent help. My mom inherited a 26ft freightliner 2012 with cummins engine isb 6.7 GM 2250 expedite truck. Recently, the dpf light was flashing frequently and a parked regeneration was done, sometimes once a day. Well, three weeks ago, the check engine light and the dpf lamp appeared on the dash board. Since the vehicle was in use, a parked regeneration was done however, the dpf light kept on flashing. DEF tank was full by the way. Before i could make it back to the mechanic, 'the stop engine light' came on as well. The vehicle was diagnosed by the mechanic and i was asked to replace the turbo. Also, the 2 dpf filters were taken off and sent to a specialist to be cleaned. The intake sensor (Nox sensor) was also changed and the DEF sensor was also replaced. After all this, the the stop engine light is still on and the dpf lamp is on as well. I have read extensively and researched using the tools available on this site however, i can't seem to find out what might be the issue. The mechanic is as frustrated as i am. The EGR seems to be working fine and there are currently no fault codes being displayed by the cummins incite diagnostic. I appreciate any any assistance i can get.
Pm gearhead
PS. I welcome any recommendations for cummins mechanic shop located in Maryland.