1989-1993 Dodge 5.9L Cummins Tools

Tools for the 1989-1993 RAM 5.9L Cummins

The first-gen 5.9L is about as hands-on as a diesel gets. It is an inline-six with two valves per cylinder and a solid-lifter camshaft, fed by a Bosch VE44 rotary pump that is gear-driven off the front gear train and fully mechanical. There is no engine computer and no OBD port to plug into, so the work owners do on these D250, D350, W250 and W350 trucks is wrench work: setting valve lash, servicing the front gear housing, pulling injectors and the injection pump, and bleeding the fuel system. Each of those jobs leans on a few Cummins-specific tools. For everything else on the engine, start at our Cummins parts hub.

The jobs and the tools they take

• Valve lash. Lash is set cold at 0.010 in intake and 0.020 in exhaust and checked every 24,000 miles. You need a barring tool to turn the engine (OTC 7471A or Cummins 3824591), a feeler gauge, and a torque wrench for the 18 ft-lb locknuts. In a pinch, the 22 mm alternator nut will bar the engine over without the tool.
• KDP tab. The killer dowel pin is the front gear housing alignment dowel that can back out on 1989-1998 12-valves. The tab install calls for 8, 10, 15 and 16 mm sockets, a 3/8 in square-drive bar for the belt tensioner, the barring tool, a brass punch, a feeler gauge, an OTC 4507 front-seal driver and a dead-blow hammer.
• Fuel system. Removing the injection pump takes a pump gear puller, the injectors come out with a 12-valve injector puller, and bleeding afterward means working the hand primer on the cam-driven transfer pump. A slotted jack handle over the primer saves your hand when it takes hundreds of strokes.

What goes wrong

The classic first-gen DIY mistake is a snapped timing pin. It happens when the engine gets rotated with the pin still engaged, and it shows up most during valve lash and KDP work, the two jobs where you bar the engine around again and again. Build one habit: check that the pin is out every time the barring tool goes on. The rest of the tools here are about doing a job cleanly. A gear puller draws the injection pump gear off evenly, a thread chaser cleans up existing threads rather than cutting new ones, and a valve spring compressor holds the spring so the keepers come out and go back in under control.

Factory tools vs. aftermarket

The OTC and Cummins service tools are the reference, and the part numbers above are the ones to look for. Aftermarket crankshaft barring tools are sold as substitutes for the OTC/Cummins tool and do the same job. For valve train work, a 12-valve spring compressor lets you remove and install valve springs on the cylinder head, and both XDP and Hamilton Cams build one for the 1989-1998 5.9L. For a home garage, the bench and the tray matter as much as any single tool. First-gen jobs spread a lot of small fasteners across the work surface, and a steel bench with a silicone tray keeps them where you left them.

What we carry

XDP covers the engine-specific pieces: the XD312 valve spring compressor for 12-valve engines, the XD134 injection pump gear puller listed for 1989-2018 5.9L and 6.7L Cummins, and thread cleaning chasers in M8x1.25, M12x1.5, M12x1.75 and M16x2.0. Hamilton Cams offers its own 12-valve spring compressor for 1989-1998 5.9L engines. For the bay, Wehrli Custom Fabrication builds modular steel work benches in 32 x 48, 32 x 72 and 32 x 90 inch sizes, and S&B makes a flexible silicone tool tray. Merchant Automotive supplies a right-angle grease gun adapter and a quick-disconnect tool kit, Air Lift sells an air line hose cutter, and Calibrated Power offers a Stealth Boost Tester inlet adapter for its HD regulator, sized for S300, S400, S400R and S500 turbo inlets.

Fitment notes

Most of what is here is general shop equipment that works on any bench. The engine-specific tools are where fitment matters. The valve spring compressors are built for the 12-valve head, so they suit 1989-1998 5.9L engines and not the 24-valve engines that followed. The XD134 gear puller is listed across 5.9L and 6.7L Cummins from 1989 through 2018. The Calibrated Power adapter is sized for S300 through S500 turbo inlets, so check which turbo is on your truck before you order it. Read the thread pitch on a chaser before you buy, because M12x1.5 and M12x1.75 look alike and do not swap. If you are not sure which engine is in the truck, verify by VIN.

Frequently asked questions

Do I need a barring tool to set valve lash on a first-gen Cummins?

It makes the job easier and more precise. The OTC 7471A or Cummins 3824591 barring tool lets you turn the engine in small steps, and aftermarket barring tools do the same job. Without one, the 22 mm alternator nut can bar the engine over. Either way, set lash cold at 0.010 in intake and 0.020 in exhaust and torque the locknuts to 18 ft-lb.

How do I keep from breaking the timing pin?

Never rotate the engine with the timing pin engaged. That is the classic first-gen DIY mistake, and it usually happens during lash or KDP work when you are barring the engine around repeatedly. Make checking the pin part of your routine every time the barring tool goes on.

Does the XDP injection pump gear puller fit a 1989-1993 truck?

The XD134 is listed for 1989-2018 5.9L and 6.7L Cummins, a range that includes the first-gen VE-pump trucks. Confirm against your truck with the fitment checker on the product page. Pulling the pump is only half the fuel job, so plan on a 12-valve injector puller and a way to work the hand primer afterward.

What tools does the KDP tab job take?

Plan on 8, 10, 15 and 16 mm sockets, a 3/8 in square-drive bar for the belt tensioner, a barring tool, a brass punch, a feeler gauge, an OTC 4507 front-seal driver and a dead-blow hammer. The dowel can back out on 1989-1998 12-valve engines, first-gens included. Mind the timing pin while you bar the engine around.

How do I bleed the fuel system after pump or injector work?

The first-gen feeds its VE pump with a cam-driven mechanical transfer pump that has a hand primer. Bleeding means working that primer, sometimes for hundreds of strokes. A slotted jack handle pushed over the primer saves your hand and your patience.

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.