4L80 vs 6L80: Which Transmission is Better?

When it comes to heavy-duty truck transmissions, there are few that can compare to the 4L80 and 6L80.

These transmissions are built for durability and performance, and they have a long history of being used in some of the most powerful trucks on the road.

So, which one is better? Let’s take a closer look at both transmissions to find out.

4L80 Transmission

The 4L80 transmission was introduced by GM in 1991 as a heavy-duty alternative to the lighter-duty 4L60 transmission.

The 4L80 transmission is a four-speed automatic transmission that is available with either two or four wheel drive.

The 4L80 transmission is also capable of being equipped with a manual shift mode.

6L80 Transmission

The 6L80 transmission is an evolution of the 4L80 transmission. The 6L80 transmission was introduced by GM in 2006 and is available with either two or four-wheel drive.

Like the 4L80 transmission, the 6L80 transmission is also capable of being equipped with a manual shift mode.

4L80 vs 6L80: Key Differences

The biggest difference between the two transmissions is that the 6L80 features six forward gears instead of four.

The main difference between the 4L80 and the 6L80 is their respective gear ratios. The 4L80 has a first gear ratio of 3.06:1, while the 6L80 has a first gear ratio of 2.97:1. The 4L80 also has a higher overdrive gear ratio of 0.75:1, while the 6l80 has a slightly lower overdrive gear ratio of 0.70:1.

Another key difference between these two transmissions is their respective clutches. The 4l80 has an 11-inch clutch, while the 6l80 has a 10.5-inch clutch. The size of the clutch can impact the overall strength and durability of the transmission.

Related:   Toyota Tundra 4.6 L vs 5.7 L | What's the Difference?

The last major difference between these two transmissions is their price. The 4l80 is typically more expensive than the 6l80. This is due in part to the fact that the 4l80 is a heavier duty transmission that is designed for use in larger vehicles such as trucks and SUVs.

Can You Swap a 4L80 for a 6L80?

In short, yes. The 4l60e to 6l90 swap is a popular upgrade because it allows drivers to take advantage of the six forward gears offered by the 6l90 while still using their existing 4l60e bellhousing, torque converter, driveshaft, etc.

The only downside to this swap is that it requires some custom wiring in order to make it work properly.


So, which transmission is better? That really depends on your specific needs and driving habits. If you’re looking for more power and performance, then the 6l90 is the way to go.

However, if you’re looking for a more budget-friendly option, then the 4l60e will be just fine.

Whichever transmission you choose, you can rest assured knowing that you’re getting one of the most durable and reliable transmissions on the market today.

Read More:
275/70R17 vs 285/70R17 Tire Comparison
265 65R18 vs 275 65R18 Tire Size – Deep Comparison!
Are Costco Interstate Battery Good? Explained
285 65R18 vs 275 70R18 Tire Size: Detail Comparison
Can I Use 5w20 Instead Of 5w30? Explained

Rate this post

Brian Polk

Brian is an automotive expert who has 12 years of experience in the industry. He has worked on a variety of cars, from high-end luxury vehicles to budget-friendly options, and has a wealth of knowledge on the subject. He is passionate about automobile and enjoys sharing his knowledge with others, whether they are looking to purchase a new motorized vehicle or simply learn more about the inner workings of these machines. In his free time, Brian enjoys working in his automobile workshop and spending time at the track.

Recent Posts