Harrison Page said that when he auditioned for the role of Captain Trunk, he pictured him as an extremely exasperated, frustrated man, and, therefore, chose to play him as constantly yelling at Hammer. He did that, which alerted other people in the building, and got the role.
Originally, the opening credits sequence was to have Sledge Hammer firing his gun directly at the camera and shattering it. But ABC's standards and practices department feared that Hammer firing straight at the camera would frighten some viewers and possibly leave the network liable in case a viewer had a heart attack. A compromise was reached. Hammer would fire his gun slightly to the left of the camera but still shattering the screen. Nevertheless, on the night of the series' debut, a person working for a Midwest ABC affiliate was startled by the opening sequence, panicked and threw on the station logo thinking something had gone wrong with their tape machine.
Alan Spencer originally wrote the pilot script in 1976 as a parody of Dirty Harry (1971) and its sequels. Not only did every network reject it, but executives questioned Spencer's mental health due to the exaggerated violence. It wasn't until the success of the third sequel, Sudden Impact (1983), that networks began showing an interest in Spencer's script.
The producers were so convinced the show would be cancelled that they closed the first season with Sledge accidentally destroying the city. When the show received a surprise renewal, the second season was said to take place five years before the explosion.
The first 13 episodes had canned laughter in their audio tracks. Starting with episode 14, "State of Sledge", ABC gave in to Alan Spencer's request to have the laugh track omitted from the series after he was furious because he notoriously dislikes the use of it. Because of Spencer's ownership rights to the series, the DVD release has all canned laughter deleted from the first 13 episodes.
Alan Spencer wrote the role of Sledge Hammer with David Rasche with in mind, even though he had never seen Rasche perform. He based his decision on seeing Rasche's picture and reading reviews of his stage performances.
David Rasche, described to be a very well-adjusted person, revealed in the Sledge Hammer! DVD that contrary to the relationship that Hammer and Captain Trunk had, he and Harrison Page became good friends and still, to this day, keep in touch.
Sledge Hammer's catch phrase was originally written as "I'm crazy, but I know what I'm doing." But ABC executives objected to the main character being "crazy" so it was changed to "Trust me, I know what I'm doing."
The pilot initially rated poorly with a test audience. ABC added a laugh track and screened it a second time. The test audience rated it higher the second time. Although Alan Spencer was protested strongly, ABC insisted that the series air with a laugh track. The track was removed halfway into the first season.
During a motel raid scene in "Under the Gun", two adjacent room numbers - "86" and "99" are used. These are references to Don Adams and Barbara Feldon's agent numbers in the series Get Smart (1965). "Get Smart" executive producer Leonard Stern was a consultant on this series.
The pilot was originally developed for HBO. HBO originally approached Get Smart (1965) producer Leonard Stern about developing a police show parody. Stern suggested Alan Spencer script which had been floating around for years. HBO wanted Rodney Dangerfield or Joe Piscopo, whom were both under contract with the network, to play the title role. But Spencer objected.
The DVD release of "Sledge Hammer!" proved to be a worldwide success and garnered renewed critical acclaim for the series. Many journalists cited how influential the show had been. Both star David Rasche and creator Alan Spencer enjoyed career upticks thanks to the home video release.
Although it is never stated where the series takes place, in the first episode, a fictional newspaper named "San Francisco Dispatch" is shown as a reference to Dirty Harry (1971) which took place there. In the original airing of the episode, the city name's was blurred.
Sledge Hammer only shoots a person once in the series and it was by accident and happens off-camera ("Witless"). Most of the time when Hammer fires his gun, he shoots objects or shoots the villains' guns out of their hands.
Episode 7, "All Shook Up", featured a sarcastic jab towards the series' lead-in at the time, Mr. Belvedere (1985), and caused a subsequent feud between the two shows. This bad blood carried over to The Tonight Show Starring Johnny Carson (1962), where "Mr. Belvedere" star Bob Uecker made a wisecrack about "Sledge Hammer" while guesting. This would lead Spencer to hurl an even more vicious insult at "Belvedere" in a later episode.
In 1992, New Line Cinema discussed producing a feature film version of the show with its creator, Alan Spencer But New Line wanted the film version to be a parody of Lethal Weapon (1987) and its sequels with all new characters. Spencer passed. New Line's concept then became the basis for Loaded Weapon 1 (1993)
David Rasche's character Sledge Hammer is meant to be a parody of the Clint Eastwood Dirty Harry cop character. Coincidentally many years later, David Rasche had a supporting role in the Clint Eastwood directed film "Flags of Our Fathers".