Jeep Cherokee Forum

Jeep Cherokee and Jeep Grand Cherokee 1984-2004: Why is My Jeep Leaking Oil?

Is your Jeep leaking oil? Learn how to diagnose and resolve the problem with the help of this article.

By Jerry Perez - September 15, 2015

This article applies to the Jeep Cherokee and Jeep Grand Cherokee (1984-2004).

Oil to your car is the same as blood to a human body, and just like we couldn't function right if were constantly bleeding, the engine in your Jeep can't perform as it should if it's leaking oil; also, it could face catastrophic failure. Pesky oil leaks can range from just a drop here and there, to full steams of oil escaping your engine; therefore, diagnosing and repairing oil leaks is extremely important. Follow this guide to learn the most common causes for oil leaks and how to repair them.

Materials Needed

  • 15mm, 17mm socket and ratchet wrench
  • Oil filter removal tool (optional)
  • Cleaning rags

Step 1 – Check drain plug

It could be damaged.

Some of the oil in your engine is spread all over vital components to protect it from friction, but while your engine is not running, most of the oil is housed in the oil pan. The oil pan has one dedicated drain plug, which is a large screw that is removed to drain the oil during routine oil changes. If this drain plug has weakened or is damaged, it could leak vital engine oil. Follow these steps:

  • Jack up car and secure on jack stands.
  • Locate drain plug on the oil pan.
  • Use socket or open wrench to remove drain plug and inspect its seal (possibly O-ring) as well as its overall condition.
  • Replace if needed.
Figure 1. Check drain plug condition.

Pro Tip

Some drain plugs may have a rubber O-ring around them, so inspect and replace O-ring if needed.

If that is not the reason for the oil leak, move on to this next step.

Step 2 – Check gaskets

They could be worn out.

Your Jeep's engine has many areas where two parts come together, and in between those two parts there is always a gasket. There is a main head gasket and an oil pan head gasket that have been reported to leak by Cherokee owners in various forums. You can follow these steps to inspect the gaskets.

  • Open the hood.
  • Locate the engine block, where the top end and bottom end meet.
  • Inspect its perimeter looking for any signs of oil leakage.
  • There should be no oil in the outside of the block, so if there is, visit the dealership or repair shop to replace gasket.
  • Repeat same steps for the oil pan gasket.
Figure 2. Excessive grime on any surface is a sign of an oil leak.

If the result of that does not turn up the source for the oil leak, move to this next step.

Step 3 – Check oil filter

It could be damaged.

In most vehicles, and specially Jeeps which may sometimes perform off-road duties, oil filters can easily be damaged by debris and cause leaks. The oil filter sits connected to the engine and is exposed to the elements.

  • When the engine is cool, jack up the vehicle and support on jack stands.
  • Locate oil filter, which is large cylinder attached to the side of the engine near the oil pan.
  • Inspect oil filter for damage, but do not twist off cylinder unless the oil pan has been emptied.
  • Inspect around oil filter for signs of oil leaks.
  • On the 4.0L engine, the oil filter housing adapter is a common source for leaks.
  • Replace filter if needed.
Figure 3. Oil leak by oil filter.

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