“Mike and I have been together for a long time, so from a personal standpoint this is difficult for me,” said Allmendinger. "We’ve worked really well together and I think our personalities really complemented each other.
"Mike and I both came into this year really committed to working on our weaker areas. I know we both tried our best to be better and communicate better - I couldn’t have asked for either of us to try any harder. Sometimes though, you need to take a step back and have a new perspective or new set of eyes look at things to move to the next level."
Prior to joining Richard Petty Motorsports, Erwin served as crew chief position with the No. 16 team at Roush Fenway Racing and driver Greg Biffle. Erwin joined that team in May 2007 and during his tenure at RFR, led Biffle to five victories, 36 top-five and 66 top-10 finishes. Erwin’s team made the Chase for the Cup three times.