2007.5-2009 Dodge 6.7L Cummins Tuning

Tuning on the 2007.5-2009 RAM 6.7L Cummins

The 6.7L Cummins replaced the 5.9L in mid-2007 and brought a lot of new hardware with it: a Holset HE351VE variable-geometry turbo with a built-in exhaust brake, cooled EGR, a diesel oxidation catalyst, a NOx adsorber catalyst and a diesel particulate filter. Fuel comes from a Bosch CP3 pump feeding a common rail. These pickups have no DEF system. They handle NOx with EGR and the NOx adsorber, which loads the DPF faster than later trucks do. Factory ratings were 350 hp and 650 lb-ft with the 68RFE automatic, 350 hp and 610 lb-ft with the G56 manual, and 305 hp and 610 lb-ft for the 3500 Chassis Cab. One engine computer manages all of it, which is why tuning this truck is as much about transmission and aftertreatment behavior as it is about power.

What fails and why

Added power finds the weak links on this engine. The 6.7L runs higher cylinder pressure than the 5.9L, so its head gasket has less margin once boost goes up. The stock VGT and the 68RFE are the other pressure points. The problems that show up after tuning are head gasket failure, a sticking or failed VGT, and torque converter slip, and the standard advice for turbo life is to avoid aggressive tuners on the stock turbo. Manual trucks have their own ceiling. The G56 is rated for under 700 lb-ft of input torque, and its bellhousing can crack, or its input bearing fail, when performance modifications push past that. If your truck already has regen complaints, start on the factory side. Chrysler and Cummins issued several software reflashes for DPF loading on 2007.5-2012 trucks, so confirming the truck has its current factory calibration comes first.

Stock replacement vs. upgrade

On this platform, staying stock is a real choice. A current factory calibration addresses DPF loading complaints and keeps the head gasket, VGT and transmission inside the limits they were built for. If you want more, stay inside CARB Executive Order coverage. Programmers and calibrations for the 2007.5-2009 6.7L carry EO numbers on a per-part-number basis, and coverage varies by year, so only an EO-numbered part number for your exact year belongs on a street truck. Some hardware upgrades carry their own EO and add airflow without changing the calibration at all. Whatever you pick, plan the supporting parts before the power: head studs, an upgraded converter and valve body, and a lift pump are the hardware commonly listed alongside tuning for these trucks.

What we carry

This collection covers the tools and hardware side of tuning. The HP Tuners MPVI4 is the vehicle interface that connects HP Tuners software on a laptop to the truck for scanning, datalogging and writing calibrations. From Calibrated Power / DuramaxTuner we carry the DSP Switch Bracket No Drill Mount, listed for 2006-2022 5.9L and 6.7L Cummins trucks, which gives a DSP selector switch a mounting spot without drilling the dash. Browse our full tuners collection for more, and run the fitment checker on each product page against your truck.

Fitment notes

Start with the engine. Early 2007 Rams still carried the 5.9L, and the 6.7L arrived mid-year as the 2007.5 truck, so verify a 2007 by VIN before ordering anything engine-specific. The 2500 and 3500 pickups came with either the 68RFE automatic or the G56 manual, and that matters here: the automatic's line pressure strategy lives in the same calibration, and the manual has its own torque limit. The 3500 Chassis Cab used the G56 manual or the Aisin AS68RC automatic and a lower factory rating, and the 4500/5500 Chassis Cabs sit on a different chassis, so read each listing carefully for those trucks. These trucks were badged Dodge Ram, which is how many vendor fitment lists name them. Before you buy any software-based product, confirm your exact year and controller are supported and that the calibration you plan to load carries an EO number for that year.

Frequently asked questions

Will tuning hurt my 2007.5-2009 6.7L Cummins?

It can if the power outruns the hardware. The 6.7L head gasket has less margin than the 5.9L's, and the stock VGT and 68RFE are the parts that suffer first, with head gasket trouble, VGT sticking and converter slip the usual results. Plan the supporting hardware and stay with EO-covered calibrations.

How much torque can the G56 manual take?

The G56 behind the 6.7L is rated for under 700 lb-ft of input torque. Past that, the bellhousing can crack and the input bearing can fail. The manual trucks make 610 lb-ft from the factory, so there is less than 90 lb-ft of headroom before that limit.

My truck regens constantly. Should I tune it?

Check the factory calibration first. Chrysler and Cummins released several software reflashes for DPF loading on 2007.5-2012 trucks. These pickups also load the DPF faster than later DEF-equipped trucks because they rely on EGR and the NOx adsorber, so a current factory flash is the first thing to confirm.

What should I look for in a tuner for a street-driven truck?

A CARB Executive Order number that covers your exact model year. EO coverage is listed part number by part number, so one product line can include both covered and uncovered versions. If a listing does not show an EO for your year, leave it off a street truck.

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.