WARREN — Cheap Trick still runs like a well-oiled machine, even with a couple of after-market parts.

Guitar player Rick Nielsen and lead singer Robin Zander have been performing together for more than 45 years, and they’re usually joined on stage by bass player Tom Petersson, who — except for a few years in the mid ’80s — has been making music with Nielsen even longer than Zander has.

Petersson is on the sidelines after open heart surgery earlier this year, so Zander and Nielson were accompanied Wednesday at W.D. Packard Music Hall by their sons. Daxx Nielsen has been the drummer since 2010, and Robin Taylor Zander Jr. is filling in on bass.

Cheap Trick has been a favorite band of mine since my first show in 1979, and I’ve seen the group about 10 times over the years. That’s nothing, though. Someone was holding up a sign saying it was his / her 127th show. Packard could have used a few more of those diehards Wednesday because the venue only was half full.

The structure of the set doesn’t vary much. Headlining shows are around 20 songs and about 90 minutes. More often than not, it’s going to open with “Hello There” and close with “Goodnight Now” and “Surrender.” “I Want You to Want Me” and “Dream Police” are almost certain to be in between.

All of those things were true Wednesday. But for a band with a catalog as deep as Cheap Trick, there’s room for plenty of variety within that framework.

Wednesday night’s set included the band’s first single, “Oh, Candy,” and “Boys & Girls & Rock & Roll,” a track from its 2021 album “In Another World.”

It included some rarities (“Radio Lover”) and many of the songs that formed the setlist for the 1978 live album “Cheap Trick at Budokan” that was its commercial breakthrough.

It’s cool to hate on “The Flame,” a late ’80s hit for the band at a time when the record label forced it to use outside songwriters after a few albums without a successful single. It wouldn’t make a list of my 20 favorite Cheap Trick tracks, but it’s a great pop song that showcases Zander’s vocal prowess.

Wednesday the song started acoustically with just Zander’s guitar and voice before the rest of the band joined in and it swelled to its full force.

Nielsen called Zander his favorite lead singer, and at age 68 Zander’s voice still is an expressive, powerful instrument. There was a lot of echo on some of his vocals and his son occasionally was doubling him, but he’s still a pleasure to hear.

Young Zander also gave Dad a rest by taking lead vocals on “Downed” and handled it nicely.

Nielsen isn’t as manic as he was in the ’70s, but he paces the stage with an amazing assortment of rare and one-of-a-kind guitars (breaking out that five-neck monster for “Goodnight Now”), flinging custom guitar picks to the crowd and making droll comments between songs.

Early in the set, Nielsen said he texted Dave Grohl that he was at his birth place, but he hadn’t responded. Later on he said, “I just heard from Dave Grohl. He isn’t showing up.”

Nielsen and Zander didn’t need any surprise guests Wednesday. Their sons were more than up to the job.