Grease vs Oil (Differences + How to Choose One)

You need a new lubricant for your car, but you’re not sure whether you should choose grease or oil.

What are the benefits of using grease vs oil?
What is each type used for?
What suits your car better?

In this article, we’ll help you clear up these questions and give some pointers on choosing the right lubricant for your vehicle parts.

This Article Contains:

Automotive Grease vs Oil: What’s the Difference?
Grease vs Oil: What They’re Used For
Grease vs Oil: Which One Is Better?
How to Choose the Right Lubricant

Let’s begin!

Automotive Grease vs Oil: What’s the Difference?

Automotive grease and engine oil (mineral oil) are both a type of automotive lubricant used for the lubrication of car engine parts.

Both lubricating grease and oil contain common ingredients, including a base oil and additives.

The primary difference between the two is that grease contains a thickening agent along with the base oil, affecting its consistency and viscosity. The thickener turns grease into a thickened oil, which is much stickier and solid (or semi-fluid).

Apart from lubrication, both grease and oil serve several purposes, including:

Controlling and maintaining the temperature of your engine
Keeping the engine clean and free of dust
Protecting the engine against moisture damage and corrosion
Preventing friction between metal parts and delaying engine wear

NOTE: As a point of interest, you might have heard of yellow grease or brown grease. These aren’t automotive greases but food production byproducts. Yellow grease is used as cooking oil, and brown grease is waste collected from a grease trap or grease interceptor.

Now, let’s get back to automotive grease and oil.
What are lubricating grease and oil used for?

Grease vs Oil: What They’re Used For

On a base level, both oil and grease perform similar functions. But certain applications do demand the special use of either grease vs oil.

Let’s see what each type of lubricant is better suited to:

A. Grease Lubrication

A grease lubricant has a higher viscosity than oil. Thanks to the addition of synthetic grease additives and a thickening agent, grease lubrication is ideal for the following applications:

Heavy-duty protection: Wheel bearing lubrication and other components that require a long-lasting and heavy-duty barrier against friction.

In hard-to-reach engine parts: For lubrication of engine components where you can’t install an oil circulation system.

Sealing engine parts exposed to contaminants: Lubricating grease is better at sealing parts from water and dust contaminants due to the thickener that gives it a sticky consistency.

Lubrication of sliding metal parts: Grease lubricant does not flow as fast as oil. Therefore it acts as a dry lube and better protects sliding parts against friction while ensuring smooth operation.

Specialty grease applications: Polyurea grease is ideal as a sealed-for-life lube; lithium grease is used for wheel bearing lubrication, whereas calcium grease works as lube for marine applications. These greases contain specific grease additives that make them favorable for certain jobs.

Lubrication of worn-out parts: The grease additives provide stronger protection for worn seals than lubricating oil. This is because worn seals and bearings retain a dry lube, like grease, better than oil.

Noise reduction: Grease lubricant better absorbs noise than oil due to its thick consistency.

B. Oil Lubrication

Certain applications will require lubricating oil rather than grease. The type of motor oil used could be mineral oil or synthetic oils, with the necessary additives.

Motor oil is best used for the following:

Oil lubrication of fast-moving parts: For lubrication of fast-moving engine parts that would be slowed by grease lubrication.

Cooling down engine parts: For cooling down engine components and heat transfer from oiled bearings.

Lubrication against extreme friction: For lubrication of parts that experience extreme friction, like oiled bearings.

As a high temperature lube: Grease suffers oil separation due to oxidation at a high temperature, making oil a better choice here.

So what are the benefits of these lubricants?

Grease vs Oil: Which One Is Better?

There is never a bad lubricant when it comes to grease and motor oil. Both have advantages that give them an edge over certain applications.

Let’s take a closer look at these advantages:

A. Advantages of Automotive Grease

Grease consistency is ideal for many applications. The thickening agent gives it the following advantages over engine oil:

Excellent start-stop performance since it’s a dry lube that doesn’t drain when the engine is turned off
Better control over leakage for worn seals and bearings due to grease consistency
Better at capturing contaminants and keeping the engine clean
Does not require a filter or pump to function, it works on its own
Long-lasting protection when it comes to water resistance
Less amount can go a long way without needing a refill

In contrast to grease, lubricating oil has the following advantages.

B. Advantages of Engine Oil

Engine oil is ideal for high-speed and fast-moving applications. It has many benefits (regardless of whether it’s mineral oil or synthetic oil), primarily:

Better at heat transfer and temperature control
Does not suffer from oil separation at high temperatures, unlike grease
Consumes lower amount of energy while operating
Doesn’t contain a thickener, so you don’t have to worry about incompatibility with other synthetic oils
Gives cleaner, mess-free handling
Easier to change and drain out
Better and more long-lasting for oiled bearings (roller and ball bearings)

Keeping these benefits in mind, how do you decide which lubricant is right for the job?

How to Choose the Right Lubricant

Whether you need oil or grease will depend on the nature of your task. Let’s look at some examples for a better picture.

Here’s when you’d use an oil lubricant:

Engine parts that frequently reach a high temperature require engine oil lubrication since oil can circulate the heat around, cooling down the engine. Gearboxes also require gear oil instead of grease for lubrication. Grease may easily bleed under high pressure. Gear oil, on the other hand, is perfect for such high-speed applications.

And here, grease works better:

Car equipment that frequently comes in contact with moisture is better suited for grease since oil lubricant can easily wash away when exposed to water. Specialty greases like lithium grease or polyureas grease will work better for heavy-duty and long-lasting applications.

Remember, using the wrong lubricant can lead to improper lubrication. For example, you don’t want to use synthetic oils for load-bearing lubrication since lithium grease or calcium grease would be a better fit here.

Your vehicle’s manual is also an excellent guide to help determine which lubricant to use for your car parts.

You may also choose specially formulated lubricants for specific applications. For example, oils like gear oil and gun oil are formulated with specific viscosity ranges to suit their job.

Closing Thoughts

Whether you use grease or an engine oil lubricant, the important thing to remember is to set a regular replacement routine. Most lubricants don’t last forever, and improper lubrication may cause engine failure and other serious problems.

Choose a lubricant that is best suited for the job. Both oil and grease have their advantages, and you should choose one with the right additives for maximum efficiency.

Fortunately, you can easily avoid improper lubrication and engine wear with routine car maintenance.

Why not reach out to AutoNation Mobile Service for this?
We are a mobile car repair and maintenance service that offers competent and upfront pricing along with experienced mechanics who’ll take care of all your car repair needs.