Diesel Engine problems of the 2005 Dodge SRT-4

I bought my 2005 Dodge ram 2500 4x4 quad cab with the cummins engine in febuary 2005since then the vehicle has been in the shop 6 times for a high pitched squiking sound from the engine, at first the belt tensiner was replaced, proglem persisted, second time the serpertine belt was replaced, still persisted, third time the water pump was replaced, problem still exists, fourth time the cam shaft was replased, no avail,fith the harmonic balace was changed but its still there, so on the six atempt the dealer gave it back to me and said "we cant fix it, file for lemmon law" this hasbeen a nightmear for me the manufacturer has not been cooperative and we went to arbitration and the representarive of the manufacturer admited al my complaints but wanted to dismiss the charges on a technicality that the lemmon law form was e- mailed to the wrong address which was provided by a customer service rep of Dodge, as to say the problem persists, the case was extended to a final repair and now the truck is miss firering and the check engine light is on. . . . . A new problem on a truck that only has 6000 miles.