2007.5-2009 Dodge 6.7L Cummins Downpipes

The downpipe on the 2007.5-2009 Ram 6.7L Cummins

On the 6.7L Cummins, exhaust leaves the cast-iron manifold and drives the Holset HE351VE variable-geometry turbo. From the turbine outlet, the downpipe drops the exhaust into the factory aftertreatment: a diesel oxidation catalyst (DOC), a NOx adsorber catalyst (NAC) and a diesel particulate filter (DPF). The downpipe is part of that emissions system, and it is a service part. When one is damaged or a joint leaks, you replace it with the same design so the catalysts and filter keep getting the exhaust flow they were built for. The same turbo is also the factory exhaust brake, closing its nozzle to build backpressure, so a tight seal from the turbo outlet back matters every time you use it.

What fails and why

There is no documented downpipe failure pattern on this platform. The exhaust trouble that is documented sits right next to it. The cast manifold upstream can crack and its studs can break with heat cycles and miles, and the signs are a tick at cold start that fades as the engine warms, soot streaks at the manifold or turbo flange, and lost boost. If you see soot around the turbo outlet, trace it before ordering parts, because a leak at the manifold and a leak at the elbow or downpipe joint can look alike from above. The DPF loading problem on 2007.5-2012 trucks is a separate issue. It comes from the no-SCR design running richer and making more soot, and no downpipe part changes that.

Replacing it the right way

Downpipe work on this truck is repair work. Replace a cracked elbow or damaged pipe with a part built for the 6.7L, and fit new gaskets and clamps at every joint you open. If what you really want is a different sound, look or flow, the place to do it is behind the DPF. A DPF-back system (MBRP calls its version filter-back) replaces only the tailpipe section, keeps the DOC, NAC and DPF where the factory put them, and fits every pickup cab and bed length. You will find those systems in our exhaust department.

What we carry

This collection holds the BD Diesel 1045101 cast turbo exhaust elbow, listed for 2007.5-2012 Cummins. It is a cast replacement for the elbow at the turbo outlet, the part to reach for when the original is cracked or damaged. Gaskets, the BD Diesel V-band clamp and manifold hardware for the same job are in the exhaust accessories and manifold collections for this truck.

Fitment notes

The BD Diesel elbow is listed for 2007.5-2012 Cummins, which covers the 2007.5-2009 6.7L. Confirm you have a pickup before ordering exhaust parts: the 3500 chassis cab routes its exhaust differently, and the 4500/5500 chassis cabs ride on a different chassis where most pickup parts do not interchange. If you have a chassis cab, call us first. 2009 was a running-change year for the turbo, which gained a turbine-housing access port for VGT cleaning, so if you are replacing the turbo along with the elbow, match both to your truck. These trucks were badged Dodge Ram. Verify by VIN.

Frequently asked questions

What does the downpipe do on a 2008 Ram 2500 with the 6.7L?

It carries exhaust from the HE351VE turbo outlet down to the factory aftertreatment: the oxidation catalyst, NOx adsorber and particulate filter. It is part of the factory emissions system and gets replaced like for like when it is damaged. Exhaust changes for sound or looks happen behind the DPF with a DPF-back system.

I see soot near my turbo. Is it the downpipe or the manifold?

It could be either, so trace it before you buy. On these trucks the cast manifold can crack and its studs can break, which shows up as a cold-start tick that fades as the engine warms, soot streaks at the manifold or turbo flange, and lost boost. A leak at the elbow or downpipe joint leaves soot at that joint instead. Our shop in Wildwood, FL can find the source and fix it.

Will a new downpipe part fix frequent regens on my 6.7L?

No. Frequent regens on 2007.5-2012 trucks come from DPF loading: without SCR the engine runs richer and makes more soot. Let regens finish, limit idle time and run low-ash CJ-4 oil, and get the truck scanned if you see derate or filter-full messages.

Not sure what fits? Call the shop at the number in the header, or use the fitment checker on any product page. We install everything we sell.