2004.5-2007 Dodge 5.9L Cummins Axle & Driveline Parts

Axle and driveline on the 2004.5-2007 RAM 5.9L Cummins

Dodge moved the heavy-duty Ram from Dana to American Axle for 2003, so every truck on this platform uses AAM hardware behind the 5.9L Cummins. Four-wheel-drive trucks get an AAM 9.25-inch front axle with 33-spline shafts, unit hub bearings and a central axle disconnect that engages the front axle in 4WD. The 3500 and heavier-duty 2500 configurations carry the AAM 11.5 rear: an 11.50-inch ring gear, 30-spline full-floating shafts and a 14-bolt cover sealed with a reusable rubber gasket. Factory ratios were 3.42, 3.73 and 4.10. Power gets to the front through a chain-driven NV271 (manual shift) or NV273 (electric shift) transfer case that holds 2.0 qt of Mopar ATF+4.

What fails and why

The 3rd-gen front suspension is stout overall, but the front unit hub bearings and ball joints on the 2003-2009 AAM front end are its weaker pieces, and wear depends on mileage and how the truck is used. Watch for a hub that clicks when you rotate it by hand, play when you rock the tire top to bottom, and ABS codes. Worn ball joints add to wander and death wobble. The long-term fix is rebuildable ball joints and serviceable hub conversions. The transfer case has its own risk: water from fording or submersion contaminates the ATF+4 quickly, which shows up as milky fluid and chain or bearing noise.

Gear oil and service

Fluid is the easy part to stay ahead of. The front axle takes 2.45 qt of 75W-90 GL-5 synthetic. The AAM 11.5 rear takes 3.8-4.2 qt of 75W-90 or 75W-140 full synthetic, with 75W-140 the call for heavy towing. Under severe service, the maintenance schedule changes differential fluid every 15,000 miles. For the transfer case, published intervals disagree, so follow your owner's manual.

Stock replacement vs. upgrade

At a fluid change, the factory rear cover and its reusable rubber gasket can go back on. The upgrade path is a finned or deep aluminum cover, which adds fluid capacity for trucks that tow. Several covers here are heavy-duty cast aluminum. Pair one with 75W-140 synthetic in the rear and you have matched the heavy-towing spec for the 11.5.

What we carry

Rear covers for the AAM 11.5 come from Pacific Performance Engineering, Mag-Hytec, BD Diesel and Wehrli Custom Fabrication, along with the Banks Power Ram-Air differential cover kit. Front 9.25 covers come from PPE, Mag-Hytec and BD Diesel, and BD also offers a front-and-rear cover pack. For the small parts, there is the PPE 138051002 rear cover gasket, the WCFab WCF100217 rear cover bolt kit and the ATS Diesel Performance 402-009-1000 drain plug for ATS pans and covers. Gear oil comes from Hot Shot's Secret (Adrenaline and Blue Diamond lines), Lucas Oil and Royal Purple Max-Gear 75W-140. You will also find the XDP XD1022 vehicle speed sensor with pigtail, listed for 1995-2006 5.9L Cummins.

Fitment notes

These trucks were sold as the Dodge Ram; RAM became its own brand in 2010, and our catalog files them under RAM. Rear parts split by axle, so count the cover bolts (the 11.5 uses 14) and check ring-gear size before ordering covers, gears, shafts or seals. The Mag-Hytec AA 14-10.5 cover is listed for 2003-2006 2500s with the AAM 10.5; buy it only if your axle is confirmed as a 10.5. The AFE 46-70032 is a Dana 80 cover, so check your axle before ordering it. Front axle parts do not interchange with the 1994-2002 Dana 60, and cab-and-chassis trucks use different axle and suspension specs from pickups. The XDP speed sensor listing stops at 2006. On a 2007, confirm the 5.9L engine, since the 6.7L took over for trucks built after January 1, 2007. Verify by VIN.

Frequently asked questions

What axles are under my 2004.5-2007 Ram 5.9L?

American Axle at both ends. 4x4 trucks use the AAM 9.25-inch, 33-spline front, and the 3500 and heavier-duty 2500 configurations carry the full-floating AAM 11.5 rear with a 14-bolt cover. The Dana 60 front was used only through 2002.

How often should I service the transfer case?

Published intervals for the NV271 and NV273 conflict, so follow your owner's manual. Both cases are chain-driven and hold 2.0 qt of Mopar ATF+4. If you have forded deep water, check the fluid; milky fluid means water got in, and it breaks down lubrication quickly.

Why do my front hubs click?

The unit hub bearings on the 2003-2009 AAM front end are one of the weaker parts of an otherwise solid front suspension. A hub that clicks when you turn it by hand, play at the top and bottom of the tire, or ABS codes all point there. Serviceable hub conversions are the long-term fix for owners keeping the truck.

Which gear oil should I run if I tow heavy?

Run 75W-140 full synthetic in the AAM 11.5 rear; that is the heavy-towing spec, and the axle takes 3.8-4.2 qt. A finned or deep aluminum cover adds capacity on top of that. Keep the front on 75W-90 GL-5 synthetic.

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.