• 2022

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Oil Pump Replacement for a 2016 Dodge Caravan 3.6L Pentastar

Most oil pumps are a single-stage design. In other words, the displacement of the pump body is fixed and the volume of oil pumped is based on the rotational speed of the pump. As the pump rotates faster, the volume of oil pumped increases. The oil pump used in the Pentastar (3.6L V6) engine is a two-stage design (the volume of oil pumped is not based on pump speed). The displacement of the pump is not fixed; rather, it has a variable displacement capability.

The pump is equipped with a slide mechanism that, when it moves, changes the displacement of the pump. In addition, it uses an on-off solenoid for two-stage pressure regulation. The pump and solenoid are not to be disassembled. Both of these components are non-serviceable items and are to be replaced as a complete assembly. Figure 1 shows the back side of the Pentastar oil pump.

FIGURE 1 | OIL PUMP

FIGURE 1 | OIL PUMP

Low pressure mode regulation (solenoid on) is approximately 200 kPa (29 psi) and high-pressure mode regulation (solenoid off) is approximately 450 kPa (65 psi). The Powertrain Control Module (PCM) switches the pump between stages based on engine operating conditions, oil and coolant temperatures, speed and load. Under most typical conditions, the pump will run in low mode from idle up to around 3,000 RPM, and switch from low to high mode between 3,000 and 4,000 RPM.

The oil pump is mounted to the bottom of the cylinder block and chain driven by the crankshaft sprocket at a 1:1 drive ratio. The oil pump pick-up tube is attached to the oil pump and supported at the windage tray. There is a pressure relief valve in the oil pump that is only activated on a cold start or for emergency relief since the oil pump output is self-regulating.

Oil Pump Diagnostics

As a rule, single-stage oil pumps rarely fail. Dual-stage oil pumps are much more complex and can encounter operational issues, although such issues are not common. The most likely condition your customer will see is low oil pressure. When this occurs, the oil pressure lamp on the instrument panel will illuminate. Low oil pressure does not indicate that there is a problem with the oil pump. Other conditions can exist. These include a low oil level in the crankcase, the wrong viscosity oil being used and a build-up of sludge in the oil pan and pick-up tube. Before prematurely assuming that the oil pump is bad, verify that the aforementioned conditions do not exist. After completing this task, you can further explore the reason for the low oil pressure problem.

If there is a specific problem with the oil pump, a Diagnostic Trouble Code (DTC) will be set and stored in the PCM. One of three codes can be set: P06DA, P06DE, and P06DD.

It is important to note that the Stuck On and Stuck Off diagnostic calibrations are reversed from the fault code descriptions. Reading what the diagnostic is checking for as a failure mode will appear to be opposite of what the fault description is calling out. This means that the Stuck Off diagnostic test is actually checking for a Stuck On condition, and the Stuck On diagnostic test is actually checking for a Stuck Off condition. This IS NOT incorrect.

Since the oil pump operates in high mode when the solenoid is not energized (off), it is more likely for a P06DE-Engine Oil Pressure Control Circuit Stuck On fault to set due to a wiring or connector issue on this system. The P06DE fault detects a pump stuck in high mode failure. On the other hand, the P06DD fault detects a pump stuck in low mode failure, the more likely case. If it is determined, after following the prescribed steps in the diagnostic manual, that there is a problem with the oil pump, it must be replaced as the pump and solenoid are not serviceable items.

Replacing the Oil Pump

Replacing the oil pump begins with draining the oil and removing the belly pan (see Figure 2). This will allow access to all the components that must be removed to access the oil pump (refer to the specific procedures in the appropriate service manual). After the upper oil pan has been removed, remove the oil pick-up, then disconnect the engine wire harness from the oil pump solenoid electrical connector. Depress the connector retention lock tab to disengage the oil pump solenoid electrical connector from the engine block.

FIGURE 2 | BELLY PAN

FIGURE 2 | BELLY PAN

Remove the timing gear splash shield. Push the oil pump solenoid connector into the engine block, rotate it slightly clockwise, push it past the primary chain tensioner mounting bolt and into the engine.

Refer to Figure 3. Push back the oil pump chain tensioner and insert a suitable retaining pin such as a 3mm Allen wrench ①. Mark the direction of rotation on the oil pump chain ③ and sprocket ④ using a paint pen. There are no timing marks on the oil chain and sprocket. Timing of the oil pump is not required. Remove the oil pump sprocket T45 retaining bolt ② from the oil pump sprocket ④. Then, remove the retaining pin ① and disengage the oil pump chain tensioner spring ⑥ from the dowel pin ⑤.

FIGURE 3 | OIL PUMP CHAIN & SPROCKET

FIGURE 3 | OIL PUMP CHAIN & SPROCKET

Remove the oil pump chain tensioner from the oil pump. Remove the four oil pump mounting bolts, then remove the oil pump. Clean the oil pan and engine gasket surfaces before installing the new oil pump. Use only isopropyl (rubbing) alcohol, along with plastic or wooden scrapers. Improper gasket surface preparation may result in engine fluid leakage.

To install the new oil pump, follow the removal procedures in the reverse order. Keep in mind these tips: First, always reinstall the timing and sprocket to maintain the same direction of rotation. Inverting a used chain on a used sprocket will result in excessive wear to both the chain and sprocket. Second, after removing the retaining pin, verify that the oil pump chain is centered on the tensioner and crankshaft sprocket.

Next, position the oil pump solenoid connector into the engine block. Rotate the connector so that it can be pushed past the primary chain tensioner mounting bolt. Rotate the connector slightly counterclockwise and push it into the engine block until it locks in place.

Finally, when installing the oil pans, use Mopar® Threebond Engine RTV Sealant or equivalent to the gasket surfaces. The components must be assembled within 10 minutes and the attaching fasteners must be tightened to specification within 45 minutes. Prolonged exposure to the air prior to assembly may result in engine fluid leakage.

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