Fixing and Upgrading Your NV4500 Gears

If you've spent any time working on heavy-duty trucks, you've likely had a love-hate relationship with your nv4500 gears at some point. This transmission is legendary for a reason—it's a tank. Whether it's sitting behind a 12-valve Cummins or an old-school Chevy big block, the NV4500 has earned its reputation as the go-to manual box for people who actually use their trucks for work. But, as anyone who's been stranded on the side of the highway knows, it isn't exactly perfect. ...

May 14, 2026 · 6 min · Clancy Etzel