1994-1998 Dodge 5.9L Cummins Air Intake Parts

Air intake on the 1994-1998 Ram 5.9L Cummins

Second-gen trucks wore Dodge badges in these years. The 12-valve 5.9L Cummins breathes through a simple path. Air enters a sealed factory airbox with a panel filter (Fleetguard AF25541 or WIX 46272), goes through the Holset HX35 compressor, then forward to the air-to-air intercooler in front of the radiator. It comes back through the charge pipe and rubber boots, into the cast intake air horn, across the electric grid heater and into the intake manifold cast into the head. Every 1994-1998 truck got the intercooler from the factory. The grid heater handles cold starts, because this engine has no glow plugs.

There is no mass-airflow sensor, no MAP sensor used for fueling and no throttle body. The Bosch P7100 inline injection pump is fully mechanical. So intake parts on this truck do two jobs: get more air in and keep it cooler. They do not change fueling.

What fails and why

Charge-air boots. Boots slipping or splitting under the clamps is the number-one intake-side problem on these trucks, and it happens at any age. You get low power, smoke and sometimes a whistle under boost. Owners often chase the fuel system before they find a boot that walked off the intercooler pipe. Check the boots and clamps before you start on fuel.

Grid heater circuit. The heater sits between the air horn and the manifold and cycles pre-heat and post-heat below about 59 degrees F. Parts vendors who specialize in these trucks report the relays and the heater element as age-related wear items. A relay that sticks on can drain the batteries. A dead circuit means hard, slow cold starts with white smoke. That pattern comes from vendor experience, not a factory bulletin.

The factory horn. On a stock engine it does its job. Once airflow goes up on a modified truck, the single-inlet horn and the grid-heater plate become the limiting pieces. The signs are boost drop across the horn and higher intake temperatures.

Stock replacement vs. upgrade

If the truck is stock and running right, the job is maintenance: a clean filter, tight boots and a working grid heater. Genuine and OEM-grade parts make the most sense on the heater grid, gaskets and sensors, where exact fit matters more than flow.

Upgrades make sense when the stock pieces have become the restriction. Air-to-air intercooling is treated as mandatory on any street 12-valve, and replacement cores plus silicone boot and clamp kits are the fixes for slipped boots and heat soak. On the filter side, cold-air intakes such as the Banks Ram-Air fit these years. Past the intercooler, Banks' Twin-Ram dual-inlet manifold roughly doubles inlet area over the factory horn. All of these are airflow parts. They do not add fuel by themselves.

What we carry

• Intakes and filters: the S&B 75-5090 cold-air intake, S&B KF-1000 and KF-1035 replacement filters, the S&B 88-0008 Precision II cleaning and oil kit, and the Banks Power 42225 Ram-Air cold-air intake with the 42650 pre-filter wrap for Ram-Air filters.
• Intercoolers and piping: the Mishimoto intercooler, intercooler and pipe kit, and factory-fit boot kit, plus the XDP XD479 Xtra Cool direct-fit intercooler.
• Boots, couplers and clamps: the BD Diesel 1045210 intake hose and clamp kit and high-torque hose clamps, an S&B 4-inch silicone coupler with clamps, and a PPE 3-inch silicone hump coupler.
• Horn, manifold and grid heater: the Banks Power 42710 intake manifold system, a genuine Cummins 3929108 air intake heater grid, the Alliant Power AP0058 grid heater gasket set, Mahle G32749 heater grid and MS12435 intake manifold gaskets, and XDP's heavy-duty grid heater relay fusible link wire.
• Sensors: a genuine Cummins 3932272 intake air temperature sensor and the XDP XD1002 throttle position sensor.

Shopping for a different truck? See all intakes.

Fitment notes

The parts here are listed by engine and model year, not by cab, bed or drivetrain. Whether you have a regular cab, a Club Cab, a 1998 Quad Cab or a dually 3500, the engine and year are what you match.

1998 is the year to watch. Dodge switched from the 12-valve to the 24-valve ISB with the VP44 pump partway through the model year, and 12-valve and 24-valve horns, grid-heater plates and manifolds are different. Identify a 1998 by the engine, not the title: a 12-valve has the P7100 inline pump with a mechanical shutoff solenoid on top, and a 24-valve has the VP44 rotary pump with a wiring harness. The intercoolers, boot kits and cold-air intakes here are listed 1994-2002, which spans both engines. The Cummins IAT sensor is listed for 1998 only and the XDP TPS for 1995-1998, so 1994 owners should check those listings first. When in doubt, verify by VIN.

Frequently asked questions

Why does my 12-valve smoke and feel flat under boost?

Check the charge-air boots first. Boots slipping or splitting under the clamps is the most common intake-side problem on 1994-1998 trucks, and it often gets blamed on fuel. A whistle under boost is another clue. Boot kits, silicone couplers and clamps from Mishimoto, BD Diesel and S&B are all on this page.

Does the 1994-1998 5.9L Cummins use glow plugs?

No. It uses an electric intake grid heater between the air horn and the intake manifold. The heater cycles before and after start-up when it is below about 59 degrees F. Hard, slow cold starts with white smoke can point to the grid heater circuit.

Will a cold-air intake fix a slow truck?

Not if the problem is a split boot or a weak grid heater circuit. Intake parts on this engine change airflow and charge temperature only; there is no mass-airflow sensor or throttle body for them to talk to. Fix the leaks first, then decide whether the truck needs more flow.

Which intake parts fit a 1998?

It depends on the engine under the hood. Trucks built after the mid-year change got the 24-valve ISB, and its horn, grid-heater plate and manifold differ from the 12-valve parts. Look for the P7100 pump with the shutoff solenoid on top before you order engine-side parts.

Is an aftermarket intercooler worth it?

Every 1994-1998 truck already has an air-to-air intercooler, and intercooling is treated as mandatory on any street 12-valve. A replacement core, paired with silicone boots and clamps, is the fix for heat soak and boots that keep slipping. The Mishimoto and XDP Xtra Cool cores here are both listed for 1994-2002.

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 at our shop in Wildwood, FL.