Bought a 2021 Silverado With 8-Speed Transmission and Told The Salesman That Gear Shifting Isn't Smooth, After 30 Days I Took It To Dealership Again

If you’ve been following the ups and downs of owning a Chevy Silverado, you know that stories about its 8-speed transmission can be polarizing. Some owners praise its capability, while others share tales of frustrating hiccups. If you want to know more about the importance of transmission maintenance for the Chevy Silverado, check out my earlier article: "45,000 Miles In, I Got a Transmission Flush Done on My 2021 Silverado at the Dealership, and After Spending $400, It's..."

Recently, Torque News reader Gerrit Vander-Kamp shared his personal experience with his 2021 Chevrolet Silverado’s 8-speed transmission, which sheds light on a crucial issue and how GM resolved it. His story is one that every truck owner—especially Silverado enthusiasts—should pay attention to.

Here’s what Gerrit wrote, with some minor edits for clarity:

I bought a used 2021 Silverado with the 8-speed transmission. Before purchasing, I took it out for a test drive. When I returned, I told the salesman that the gear shifting wasn’t smooth and that the truck shuddered. The vehicle had 68,000 miles on it and was certified used, with the powertrain warranty valid up to 100,000 miles.

After owning it for 30 days, I took it to the dealership’s service department and explained the issue. After about an hour and a half, the repairs were completed.

Here are the steps they performed:

1. Drained the transmission fluid.
2. Dropped the transmission pan and filter.
3. Inspected and cleaned exposed components.
4. Installed a new gasket and filter.
5. Refilled the transmission fluid and checked the fluid level after warming up the engine.

Note:
There is no transmission dipstick in this model; GM eliminated it. Instead, the transmission now has a fill/check plug located on the upper backside of the transmission. It’s hard to spot and even harder to access!

Before any of the above service work was performed, the starting battery was disconnected. According to GM, disconnecting the battery for a minimum of 30 minutes resets the Transmission Control Module (TCM).

You can’t make this stuff up!

By the way, after the service, my transmission now shifts perfectly, with no shuddering at all.

After owning the truck for 30 days, Gerrit took it back to the dealership for repairs. This scenario isn’t uncommon, as newer trucks—no matter how fresh they are—can sometimes face mechanical or reliability issues early on. Take this story, for instance, where a 2024 Silverado was sent back to the dealership after just 594 miles of use. It highlights how even minimal usage can sometimes bring hidden problems to light.

Gerrit’s story illustrates a common issue with GM’s 8-speed transmission, particularly the rough gear shifting some Silverado owners experience. It also highlights an important lesson: persistence pays off when dealing with manufacturer warranties.

Why This Story Matters for Silverado Owners

The Silverado is one of America’s best-selling trucks, and reliability is a big reason why people choose it. However, the 8-speed automatic transmission has faced scrutiny from owners who report anything from slight gear hesitation to severe jerking and clunking. While Gerrit’s experience turned out positive in the end, it’s a reminder that being proactive about maintenance and advocating for yourself with dealerships can save you from long-term headaches.

Tips for Maintaining Your Chevy Silverado’s Transmission

Whether you’re driving a 2021 Silverado or an earlier/later model, proper transmission care is key to maximizing performance and longevity. Here are some Silverado-specific tips to keep your transmission running smoothly:

1. Stick to GM-Recommended Transmission Fluid
   Chevrolet recommends using Dexron VI Automatic Transmission Fluid for optimal performance. Using other fluids could affect shifting and cause premature wear. Check out this guide on the best automatic transmission fluids for GM vehicles.
2. Don’t Skip the Fluid Change Intervals
   Chevrolet generally suggests a transmission fluid change around 45,000 to 60,000 miles, depending on your driving conditions. If you tow frequently or drive in stop-and-go traffic, stick to the lower range. Staying on top of fluid change intervals is non-negotiable for the longevity of your Silverado’s transmission. But while features like oil life monitors can help you track maintenance, it's important to understand their limitations and whether you can fully rely on them. For a deeper dive into how these systems work and if you can trust them, read this insightful article.
3. Pay Attention to Symptoms of Transmission Issues
   Jerking, clunking, or hesitation when shifting could indicate issues like a failing torque converter, improper fluid levels, or even software calibration problems. Don’t ignore these warning signs; get them checked as soon as possible.
4. Consider a Transmission Relearn Procedure
   If you experience minor shifting issues after maintenance, ask your dealership about a transmission control module (TCM) relearn procedure. This ensures the TCM adapts correctly to your driving style.
5. Use Tow/Haul Mode When Towing
   Silverado’s Tow/Haul mode isn’t just there for fun; it changes the transmission shift points and reduces stress on the system when pulling heavy loads. This simple step can significantly extend transmission life.
6. Ask About Software Updates
   Many Silverado transmission issues are software-related. When visiting the dealership, ask if there are updates for the transmission control module. These updates often address rough shifting and improve overall performance.

As Gerrit explained, even before purchasing the truck, he noticed that the gear shifting wasn’t smooth and that the vehicle shuddered. It reminded me of another Silverado owner’s story, where the small details revealed by the dealership—whether it’s transmission issues or something as trivial as waxing and buffing—can make all the difference in how you perceive your truck. If you haven’t read it yet, this article about a 2024 Silverado owner’s first-day experience is worth a look for more dealership surprises.

Gerrit’s experience is a testament to the fact that even trusted trucks like the Silverado can encounter challenges—but with persistence and the right dealership support, problems can often be resolved. Have you faced similar issues with your Silverado’s transmission? How did you address them? Share your stories in the comments below.

Your experiences could help other truck owners navigate their own transmission woes, and who knows—you might even inspire GM to address these issues more proactively. Let’s get the conversation started.

Armen Hareyan is the founder and the Editor in Chief of Torque News. He founded TorqueNews.com in 2010, which since then has been publishing expert news and analysis about the automotive industry. He can be reached at Torque News Twitter, Facebook, Linkedin, and Youtube. He has more than a decade of expertise in the automotive industry with a special interest in Tesla and electric vehicles.