Well the problem of shaking was also when going straight so I scratched the possibility of a steering problem. Ok so an update truck was parked forever due to waiting on drive motor encoder, got the wrong encoder from our supplier sent back and finally got the right one. The reason I order that encoder was because I got a random 2H code, lotta oil was around the encoder which led me to believe that oil got inside the encoder cirtuitry. Took motor apart replaced encoder and voila. FYI I opened the old encoder and oil was inside. I guess the oil seal wasn't doing its job.