The rear axle ratio can be confusing as it doesn’t say much about the numbers. But, many major and minor aspects depend on these numbers.
While choosing the perfect fit for you, there are many things to consider, including the rear axle ratio. So, what would be the best choice between 3.42 vs 3.73?
The 3.42 is best suited for end cruising speed, whereas the 3.73 focuses on better acceleration. The 3.73 rear axle ratio has the better towing capacity, but 3.42 is for occasional towing. But the 3.42 offers better fuel economy and mileage and is suitable for flat ground. On the other hand, 3.73 is more suitable for off-road driving.
That’s not everything! We’ll get to know more in the following sections! Tag along to learn more!
Table of Contents
3.42 vs 3.73: Quick Summary
A quick overview of the entire post can quickly give you a glimpse of what you want to know. Of course, we’ll discuss those factors in detail in the next section.
Aspects | 3.42 | 3.73 |
Cruising Speed | Better | Moderate |
Towing | Occasional | Regular |
Fuel Economy | Better | Moderate |
Ground | Flat | Off-road |
Torque | More | Less |
Acceleration | Moderate | Better |
3.42 vs 3.73: Head-to-Head Comparision

When you have two rear axle ratios to choose from, you need a better understanding of all the crucial aspects.
In this part, I’ll discuss those aspects in detail and describe how important they are in comparison. Let’s get started.
The Core Ratio Difference
As the numbers suggest, the ratio is different. But the main focus is how important they are. Now, as we know, there is a ring gear and a pinion in vehicle gear.
Now, there are teeth on those. When you divide the ring’s teeth count by the pinion’s teeth count, that’s the ratio.
We can go more into technical detail, but the bottom line is ratio describes two things; one is torque, and another one is acceleration.
In this case, the 3.73 ratio is higher than 3.42. That means the acceleration in 3.42 is lower than in 3.73.
In other words, 3.73 has a better acceleration, which means it has more torque and HP (Horsepower). In terms of speed, 3.42 is much slower, which means it takes less time for 3.73 to reach a certain speed than 3.42.
But, unfortunately, it also means that if your vehicle has 3.42, it has a better top speed. For example, if the 3.73 has around 250 speed, the 3.42 will have more than that.
But there is more!
Speed
The rear axle ratio is a crucial factor for speed. As discussed in the previous section, a higher axle ratio gives better acceleration than a lower ratio.
As the acceleration is directly connected with the speed, the higher the axle ratio, the better the acceleration. And, for that, 3.73 has the better acceleration. Thus, it means it has a better starting speed than 3.42.
On the other hand, the ratio also affects the end or cruising speed too. The higher the ratio is, the lower the cruising speed. And, for that, 3.42 has a better cruising speed than 3.73.
Towing
Towing is also another factor to consider, and it affects a lot. Whether you’re towing a camper with your Suburban, or any other truck, axle ratio is crucial.
If you have a higher axle ratio, that means you have better-towing capacity. Besides, as a higher axle ratio gives a better ratio, it also gives your truck a better hauling capacity to pull heavy stuff.
So, in this case, as the 3.73 is the higher ratio, it also has better-towing capability. Besides, better acceleration helps in the process a lot too. On the other hand, the 3.42 ratio is for regular medium towing and heavy towing occasionally.
Mileage And Fuel Economy
The mileage and fuel economy are also gets affected by the axle ratio. As we know, acceleration requires more fuel economy. It means that when you have a higher acceleration, it will cost you more fuel.
And as a result, the higher the acceleration, the lower the mileage on the vehicle. In this case, 3.42 has a lower acceleration rate than the 3.73 axle ratio.
As a result, the 3.42 axle has better mileage and fuel economy than the 3.73 axle ratio.
Ground
When your vehicle is primarily run on flat ground, such as highway roads, or mainly in the city, you don’t need higher acceleration but better speed and torque as low as possible.
And in this case, the 3.42 rear axle is the best option for you.
On the other hand, if your truck is used for towing or heavy hauling and your work requires going off-road when you need more torque and better acceleration, then 3.73 will be the suitable option.
Final Verdict
Considering everything, the bottom line is, depending on your requirement, such as what you want to do with your vehicle, is the primary objective here because the ratio exists and is best suited for different occasions and contexts.
The 3.42 rear axle ratio is a better option If you’re using the truck for;
- Driving the vehicle on a regular for running errands.
- Regular highway driving and long roads.
- Medium to heavy weight or towing now and then, but not regularly.
- You need better cruising speed.
- And better mileage and fuel economy.
- Better for ground or steady road.
- Less torque.
Then, it’s suited for you.
On the other hand, 3.73 is best suited for;
- Heavy towing regularly.
- Better towing capacity.
- Fuel economy is not the priority.
- You need faster acceleration.
- Uphill or offroad.
- More torque.
Then, it will serve you better.
What Is The Best Rear-End Ratio For Towing?
The 3.55 is the best rear-end ratio for towing. When choosing the best rear-end ratio, there are many things to consider, such as acceleration, cruising speed, towing capacity, fuel economy, etc.
Besides, the size of your vehicle’s engine also plays an essential part, as well as the tire size and ground clearance.
Considering all these, the best option is the 3.55 axle ratio. The 3.55 rear-end ratio is perfect for towing and fuel economy. It has optimal acceleration, comparatively better cruising speed, and is ideal for hauling all sizes of weights.
If you need a balanced and well-served rear-end ratio, the 3.55 is the best fit for you.
But if you’re willing to compromise everything for acceleration and towing and nothing else, then 4.10 is the perfect option.
Frequently Asked Questions (FAQs)
Is 3.42 A Good Gear Ratio?
Yes, 3.42 is a good gear ratio if you use the vehicle for regular or highway roads, need better cruising speed, and have less torque. Besides, it will give you better fuel economy, but they are only suitable for heavy towing occasionally.
What Is A 3.73 Gear Ratio Good For?
A 3.73 gear ratio is suitable for heavy and better-towing capacity. Besides, it will give you more torque and faster and better acceleration which will help run the vehicle on the off roads. But it will hurt your fuel economy.
What Axle Ratio Gets Better Mileage?
The 3.31 axle ratio gets better mileage if you willingly sacrifice all the other aspects. Besides, you might also need to offer better acceleration and face more torque. But, positively, you will have better-towing capacity and cruising speed.
>>Read more: 4.10 vs. 3.73-Which Gear Ratio Is the Best.
Last Words
Now you know everything regarding the 3.42 vs 3.73 rear axle ratio. They both have their own and better offerings in the market with different purposes.
I hope you can now choose which will suit you better. If you have any queries, let us know in the comment section.
Until then, happy driving!