Getting More Power with an L5P S400 Turbo Swap

If you're looking to push past the limits of your stock truck, an l5p s400 turbo swap is probably at the top of your wishlist. It's one of those modifications that completely changes the personality of the 2017 and newer Duramax engines. For a long time, the L5P was considered a bit of a "locked" platform because of the complex ECM encryption, but now that we've cracked that nut, the sky is pretty much the limit. Bolting on a fixed-geometry S400 frame turbo is how you turn a heavy-duty workhorse into a legitimate street beast. ...

February 17, 2026 · 7 min · Tena Gustafson