All About the 5.3 Vortec Engine Oil Pump

5.3 Vortec Engine Oil Pump: Why It Fails and How To Replace It?

If you’re looking for the correct oil pump for your 5.3L Vortec Engine, you’re at the right place.

Every car needs an oil pump specifically designed to meet its requirements. If you drive a Chevy Silverado and GMC Sierra, that’s a 5.3L Vortec engine oil pump as it’s custom-made for your car.

Read on to learn more about the 5.3 Vortec engine oil pump, its problems, and how you can solve them. 

Engine Oil Pump 101

What exactly is an engine oil pump?

The engine oil pump is a device that circulates oil in your car’s engine. Put simply, it forces oil to pass through the engine to provide your engine with lubrication and remove dirt and contaminants. 

In other words, an engine oil pump helps facilitate the movement of the engine’s moving parts and does the janitor duty.

However, an engine oil pump only works well if it is compatible with the engine. 

For instance, the 5.3L Vortec engine oil pump fits well in Buick Rainier, Cadillac Escalade, Envoy, Savana, Yukon, GMC Sierra, Trailblazer, Express, Camaro, Avalanche, Tahoe, Suburban, and Chevrolet Silverado (specifically in the models from 1999 to 2020). 

Engine Oil Pump: Parts

  • The double gearwheel
  • Sliding-vane
  • Rotary-plunger
  • Eccentric rotor
  • Rotor
  • Gear

Engine Oil Pump: Functions

  • Keeping the circulation of oil within engine constants.
  • Returning the hot oil to the coolant oil inside the reservoir.
  • Using galleries to provide direction to oil movement.
  • Making engine lubricant movement easier around the engine.
  • Circulating oil to the essential parts of the engine. 

Engine Oil Pump: Working Principle

Let’s discuss the working principle of engine oil. 

An oil pump is gear-driven and powered through a crankshaft. Oil flows into the oil pump from a filter. After this, it flows across a heat exchanger and is cooled. It uses the galleries to move towards the engine’s moving parts and finally return to the sump.

Types of Oil Pumps

Following are the various types of oil pumps:

Rotor Oil Pump

Also known as the gerotor pump, the rotor oil pump consists of an inner gear that rotates within the outer rotor. Oil is pulled from the inlet port due to a pumping motion and then pushed towards the outlet port. It is mounted within the crankcase.

Twin Gear Pump

This pump is also referred to as the external pump. Mounted on the engine’s bottom within the oil pan, the twin gear pump uses intermeshing gears for pumping oil. The first gear is driven by the shaft and this, in turn, drives the second gear. 

Front Cover Oil Pump

Also known as the internal or external pump, the front cover oil pump is usually mounted before the engine cover. Its operation is similar to the rotor pump, except that the inner drive has been mounted onto the crankshaft directly. 

Why Does an Engine Oil Pump Fail?

Following are some of the causes of oil pump failure:

Wear and Tear

Over time, the oil pump is subjected to continuous wear and tear that causes it to develop issues. Your oil pump might not totally fail, but it might lose efficiency.

Low Oil

If you don’t have enough oil inside the engine, the lack of lubrication will cause extra friction. That can lead to mechanical problems leading to oil pump failure.

Oil Contamination

If there isn’t enough maintenance, the oil might get contaminated with other liquids. This can be quite harmful to your oil pump.

Improper Installation

Finally, improper installation of the oil pump is another major factor that may lead to early oil pump failure. This could also be due to loose nuts or other similar mistakes. 

What Are Common Signs of Engine Oil Pump Failure?

Some of the symptoms of a failing oil pump include:


You might notice that the hydraulic lifter is making weird noises. This may be due to poor lubrication (or a failing engine oil pump). 

Higher Engine Working Temperatures

The oil pump helps reduce friction within the engine by keeping it lubricated. This helps keep the temperatures within range. 

But a failing oil pump will have a reduced flow of oil that could lead to a rise in temperatures within the engine.

Low Oil Pressure

If the oil pump is faulty, it won’t be able to maintain pressure within the engine, resulting in a pressure drop. This can be very damaging to the engine. 

Best Engine Oil Pumps for 5.3L Vortec Engines

Let’s now talk about the best engine oil pumps for 5.3L Vortec Engines.

Melling’s Shark Tooth Pump 

Manufactured by Melling Performance, Shark Tooth pumps are specially designed for the small block Chevy market. 

It features helical cut gears and reduced intermediate shaft wear. The helical cut gears help reduce pressure pulsing and ensure less cavitation, better flow, and a smoother output.

Schumann’s New Oil Pumps 

This Schumann Sales & Service’s oil pump uses recycling to help prevent waste of oil and energy. This pump also helps solve the issues of oil flow reversion and oil aeration.

Oil Pump Replacement in 5.3L Vortec Engines

To replace an oil pump in 5.3L Vortec engines, you’ll need the following tools:

  • Oil pump
  • Jack and jack stands
  • High temp sealant
  • Oil pan gasket
  • Brake cleaner
  • Ratchet and socket set
  • Extension and swivel
  • Engine oil
  • Gloves
  • Safety glasses
  • Repair manual

Once you’ve collected all the tools, follow the steps below to replace the oil pump:

  1. Disconnect the negative side of the battery terminal. Lift the vehicle using jack stands after the parking brake has been set.
  2. Remove the serpentine belt while draining the engine oil.
  3. Bring the engine and the crankshaft to the right position using the repair manual.
  4. Remove all the oil pan bolts.
  5. Use a flat blade screwdriver to pry off the oil pan.
  6. Remove the bolts that are holding the engine crankcase and oil pump together.
  7. Hold the oil pump in place and apply pressure on the tensioner. This helps free the pump.
  8. Properly clean all the surfaces.
  9. Use the repair manual to set the new oil pump in place.
  10. Apply the right amount of sealant.
  11. Put back all the bolts in their places and tighten them.
  12. Let the sealant dry and lower your vehicle back to its position. 

Final Thoughts: 5.3 Vortec Engine Oil Pump

The correct oil pump is crucial for the health and efficiency of your engine. We hope this guide helped you learn about oil pumps and which ones work best with 5.3L Vortec engines. 

Let’s get to work and install the oil pump yourself. In contrast, if you’re getting the help of a mechanic, make sure you get the right engine oil pump for your car. 

Let us know if you’ve any queries for us by commenting below. We’re always here to help.