Waltrip, who captured the Daytona 500 10 years ago on the day racing superstar Dale Earnhardt was killed in a last-lap wreck, sobbed uncontrollably after winning the first Camping World truck series race of the year.
Rounding the final turn, Waltrip passed Elliott Sadler with a slingshot move and edged Sadler by less than half a car length. Clay Rogers, Miguel Paludo and Kyle Busch rounded out the top five.
Waltrip, who was driving for Earnhardt's team when the racing legend was killed, will be in the field Sunday for the Daytona 500.
Earlier in the day, Danica Patrick made her best NASCAR showing by qualifying fourth for Saturday's Nationwide Series race. Patrick had the best qualifying time of all until late in the session and eventually finished fourth-fastest behind Clint Bowyer, Landon Cassill and Dale Earnhardt Jr.
She was one of just four drivers to make a trip around the famed speedway in less than 50 seconds.
Patrick ran a limited Nationwide Series schedule last year and drove full time on the Indy Car circuit, where she has one career victory.
In limited practice for the Daytona 500 Friday, Mark Martin turned in the fastest lap at 196.803 mph.