Welcome to HNet, bodukegirly.
The episode you're talking about is 'Pin the Tail on the Dukes' in season 4. The scene is just over half an hour in, and goes like this:
Waylon: Along about this time, a truck was heading through Hazzard for the first time. That driver didn't have a clue about Hazzard's driving conditions.
Bo: Hang on, Hector. Here we go again.
(They swerve the first truck)
Luke: Phew! That was close.
Bo: Bo Duke, you are too much.
(Luke spots the second truck)
Luke: Bo.
Bo: What?
Luke: Bo!
Bo: Oh, my gosh. Hang on.
Waylon: I'm hanging.
(They swerve the second truck)
Luke: How do you do that twice?
Bo: There's only two trucks in Hazzard, right?