One look at Banks TorqueTubes tells you how radically different they are from the stock exhaust manifolds. Constructed of heavy-wall, 400-series stainless steel, TorqueTubes have 5/8 inch-thick flanges that are welded on both sides and then machined perfectly flat (no gaskets needed). They never crack, leak or fail. TorqueTubes tuned-length tubes produce a huge reserve of low-end torque that proves its worth on every steep grade and short onramp. Now your Workhorse climbs faster and stronger, without the transmission struggling between gears. The muscle to stay in higher gears longer not only stops annoying shift happy performance, it lessens the load on your engine and transmission. Here's power to reach freeway speed sooner for safe merging and passing. PartNumber : gbe49542 Description : Banks Power 04-07 GM 8.1L Mh-W Torque Tube System Add-On Part : NA Title : Torque Tube Exhaust Header System 04-10 GM 8.1L W-Series Motorhome No EGR Banks Power 2005-2007 Workhorse W20 Base V8.-cc Exhaust, Mufflers & Tips::Headers & Manifolds 2004-2007 Workhorse W22 Base V8.-cc Exhaust, Mufflers & Tips::Headers & Manifolds