2004.5-2007 Dodge 5.9L Cummins Engine Oil

Engine oil for the 2004.5-2007 RAM 5.9L Cummins

The common-rail 5.9 is a cast-iron inline-six with a 12-quart oil system and a spin-on filter. Factory spec is 15W-40 when temperatures stay above 0 F, or 5W-40 synthetic for any temperature. The normal change interval is 15,000 miles or 12 months, and severe service cuts it to 7,500 miles or 6 months. The TDR injector article takes a more conservative line for hard-used trucks and prefers CI-4+ oil at 4,000-4,500 miles. Pick the interval by how the truck is used, and pick the grade by the temperatures you see.

What the oil can tell you

Oil that keeps rising on the dipstick or looks thin is a warning, and it is not an oil problem. A leaking injector on this engine dilutes the oil with fuel, and the other signs are white smoke and a dead miss. Switching oil will not fix it, and a failed injector driven on can wash a cylinder. Get the injectors checked first.

Picking a grade from this page

For the factory grades, look at the 15W-40 and 5W-40 oils. In 15W-40 that means Hot Shot's Secret Green Diamond (semi-synthetic and full synthetic) and Black Diamond Outlaw, plus Lucas Oil 15W-40 CK-4, Lucas Synthetic 15W-40 CK-4 and Lucas Magnum High TBN 15W-40 CI-4. In 5W-40 it means the Hot Shot's Secret Green Diamond and Blue Diamond full synthetics. The 0W-20, 5W-20, 10W-30 and 20W-50 oils on this page, including those grades in the ADRENALINE R-Series racing line, are not grades the factory lists for this engine. Where a title lists the API category, it is CK-4 on most and CI-4 on the Lucas Magnum, so compare it with your owner's manual.

Additives

Additives are extras on top of the right grade, not a substitute for it. This page carries Hot Shot's Secret TBN Booster Fortified Oil Stabilizer, FR3 Friction Reducer and The Original Stiction Eliminator; Lucas Oil Heavy Duty Oil Stabilizer, Synthetic Heavy Duty Oil Stabilizer and TB Zinc Plus, which Lucas labels as an engine break-in additive; and the XDP XD275 X-Factor oil additive. Read each product page for its intended use and dose before adding it to a 12-quart fill.

What we carry

Oils and additives here come from Hot Shot's Secret, Lucas Oil and XDP. Most of the oils come in 1-gallon jugs, so plan on three gallons for a change at 12 quarts with the filter.

Fitment notes

Oil is not cut to one truck, so fitment here comes down to grade and capacity. The guidance on this page is for the 5.9L. The 2007 model year includes both 5.9L and 6.7L trucks, so confirm which engine you have before using this spec, and verify by VIN with us if you are not sure.

Frequently asked questions

What oil does a 2004.5-2007 5.9L Cummins take?

15W-40 when it stays above 0 F, or 5W-40 synthetic at any temperature. The system holds 12 quarts with the filter. Normal changes are every 15,000 miles or 12 months, and every 7,500 miles or 6 months for severe service.

How much oil do I need for a change?

Twelve quarts with the filter, which is three 1-gallon jugs. Get the filter at the same time; the factory filter is the Fleetguard LF16035, and the Filters page under Oil System carries replacements.

Can I run 10W-30 or a racing oil in my 5.9?

The factory grades for this engine are 15W-40 and 5W-40 synthetic. The 10W-30, 0W-20, 5W-20 and 20W-50 oils on this page are not on that list, so stick to the two factory grades for a truck that tows and works.

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.