Parrott joins RPM from his position as Research and Development Manager at Roush Fenway Racing.
The change reunites Parrott with Sadler who worked with each other at Yates Racing in 2004.
"We are happy to welcome Todd to our team and reunite him with Elliott," said Robbie Loomis, Vice President of Competition for RPM. "We appreciate all of Wally Rogers' hard work with this team for the first half of the season. He will continue to be a valuable member of RPM."
A native of Charlotte, N.C., Parrott brings with him over 15 years of experience as crew chief in NASCAR. He has 29 wins Cup competition. Two of those wins came with Sadler during the 2004 season. The 46-year-old was crew chief for driver Dale Jarrett when the No. 88 Yates Racing team claimed the 1999 NASCAR Sprint Cup Series championship.