Gear diff vs Ball diff

Gear diff vs ball diff

Except for drag cars, every RC and the four-wheeled car has two or three differentials. Every car uses at least one differential if not two or three. Ball differential and gear differential are the most common types of differentials. Do you understand the difference between ball differential and gear differential? Gear diff vs ball diff: Which is the best? If you are struggling with these questions, don’t worry because I will discuss “Gear diff vs. ball diff” in this article.

Many people are fond of RC cars, but most don’t understand the difference between ball differential and gear differential, even though these differentials are vital for a car’s control. As a result, they face vibration, terrible sounds while running the car. Moreover, a fault differential can imbalance the car while taking turns.

Therefore, I will discuss “Gear diff vs. ball diff” in this article. Besides, you will get answers to some FAQs. So, let’s start.

What is a differential?

When a car runs in a linear direction, the car’s wheels move at the same speed. But what happens when you are taking turns? Generally, the outer wheels spin further and faster while inner wheels spin slowly to make a balance. If both wheels spin simultaneously, then you would have a greater risk of an accident.

A differential is a simple device that provides equal power to the wheels when you start the engine. At the same time, it makes sure that the outer wheels are faster than the inner wheels. From this differentiation of speed of the wheels, it has got the name “differential.” However, differentials allow the wheels to maintain the average speed/ RPM of the differential all the time.

For instance, if the differential moves at 200 rpm, it will provide both wheels with 200 rpm. But when you corner the car, it will reduce the speed of the inner wheels to 150 rpm and provide the extra 50 rpm of the inner wheels to the outer wheels. So, the speed of the outer wheels would be 250.

There are various types of differentials available in the market. But the most common types of differentials may include a gear differential and a ball differential.

What is a Gear Differential (Gear Diff)

Gear differential comprises several gears that provide power to the wheels but ensure that the outer wheels get faster than the inner ones while taking turns. The plus points of gear differentials are that it is convenient to maintain since the gear diff case holds all the lubricant. So, there is less chance for the lubricant to come off the gears.

Moreover, gear differentials are cheap and durable. Besides these advantages, there are some negative sides as well. You cannot fix gear differentials externally. You have to detach the differential from the car and fill the differential with lighter or thick fluid to adjust the gear differential.

What is a ball differential (Ball Diff)?

The ball differential also serves the same purpose as a gear differential but they are composed of several small steel ball bearings instead of gears to offer the performance of a differential. The ball bearings are located between two metal rings. A screw on one side checks the tension between the two metal rings. It also controls the turning capacity of the outside wheel.

Unlike gear differentials, it is easy to adjust the ball differentials. You can externally adjust them. One has to secure the differential tightly to make it take more pressure to slip. In contrast, one has to loosen the differential to get more traction.

The negative sides of ball differentials are that you have to check the differentials every day, and they are difficult to maintain.

Gear differential vs. ball differential

The main difference between gear differential and ball differential is that the first one uses several gears to provide the service of a differential, while the second one uses small steel ball bearings instead of gears. Other differences may include:

Smoothness: ball differentials transfer powers to the wheels more evenly than a gear differential. This smoothness ultimately helps the wheels take turns easily, even when taking a hard turn.

Durability & maintenance: Gear differentials are the winner in this regard. They need almost no maintenance and have longevity. In contrast, ball differential requires maintenance.

Adjustability: A ball differential is easy to adjust. One can externally adjust them. But one cannot adjust gear differentials externally.

Weight: ball differentials are lighter than gear differentials. It is one of the many reasons why ball differentials are more popular for racing.


Gear differential vs. ball differential: which is better?

It depends on one’s preference. If you need a high resistance differential action, it is better to choose a gear differential. In contrast, if you are looking for a differential that would be best for racing competition, a ball differential would serve you the best. Because the ball differential provides greater smoothness that is convenient even for hard turning.

Why is a ball differential better?

There are various reasons why a ball differential is better than a gear differential. The ball differential comprises steel balls that move on metal rings to offer differential tasks without any backlash. But gear differentials need some play to function.

Moreover, ball differentials are externally adjustable, which is not found in gear differentials. They are also lighter than gear differentials. 


There is no doubt that differentials are vital components for RC cars. They are responsible for providing power to the wheels and ensuring a balance between them when taking turns. But most people don’t understand the difference between ball differentials and gear differentials. 

Therefore, they choose the wrong differential and ruin their excitement. In this article, I have explained “Gear differential vs. ball differential” in the most comprehensive way. So that people can choose differentials for their car as per their requirements. I hope you have found the article practical.

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