Jet... you'll need the 4" band clamp to connect it to your downpipe. Also, the stock HX-40 has the wastegate actuator setup differently than the HX-35s in the Dodge trucks. You should have the actuator assembly changed. Mine wasn't and I made it work by turning the actuator assembly head 180 degrees and rerouting my heater line. It's still very close to the exhaust manifold but it works. By the way, I love my 40. Good luck.
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98. 5 2500, 24v, 5 speed, QC, 4x4, 4. 10 LSD, short bed, Line-X liner, tow package, camper suspension, Westin nerfs, camper shell, TST PowerMax Competition, 275 RVs, Psychotty air, HX-40, 4" straight pipe exhaust, ProComp A/T 305/70/R16s, EGT/Boost pillar gauges, Grover air horns... Love my Cummins, no love for Dodge