When #78-Martin Truex Jr. won at Ponono for the #78 Furniture Row team, it was his third career win. The other two wins came with two different teams. Some other drivers who have won one race with separate teams/owners (3 or more wins):
Morgan Shepherd, four wins, four teams:
Martinsville, 4/26/1981, #5-Cliff Stewart
Atlanta, 3/16/1986, #47-Jack Beebe
Atlanta, 11/18/1990, #15-Bud Moore Engineering
Atlanta, 3/20/1993, #21-Wood Brothers Racing
Joe Nemechek, four wins, four teams:
Kansas, 10/10/2004, #01-MB2 Motorsports
Richmond, 5/3/2003, #25-Hendrick Motorsports
Rockingham, 11/4/2001, #33-Andy Petree Racing
New Hampshire, 9/19/1999, #42-SABCO (Felix Sabates)
Martin Truex Jr., three wins, three teams:(also, won all 3 races in the month of June)
Pocono, 6/7/2015, #78-Furniture Row Racing
Sonoma, 6/23/2013, #56-Michael Waltrip Racing
Dover, 6/4/2007, #1-Dale Earnhardt, Inc.
Brian Vickers, three wins, three teams:
New Hampshire, 7/14/2013, #55-Michael Waltrip Racing
Michigan, 8/16/2009, #83-Red Bull Racing
Talladega, 10/8/2006, #25-Hendrick Motorsports
Bill Blair, three wins, three teams:
Vernon, 6/18/1950, #2-Sam Rice
Atlanta/Lakewood Speedway, 4/20/1952, #2-George Hutchens
Daytona Beach, 2/15/1953, #2-Bill Blair
(Checked stats at racing-reference.info)(6-17-2015)
