2021-2024 RAM 6.7L Cummins Engine Problems: Grid Heater Bolt Failure

Class Action Investigation

Updated on January 28th, 2026 Author: Sergei Lemberg

Lemberg Law is conducting a class action investigation into engine failures in Ram 2500 and 3500 trucks equipped with the Cummins 6.7-liter diesel engine after a growing number of owners reported sudden, catastrophic engine damage traced back to a failed grid heater bolt entering the intake and destroying internal engine components.

I’m Sergei Lemberg, and for more than two decades my work has focused on identifying patterns in consumer defect complaints before manufacturers publicly acknowledge systemic problems. Individual engine failures can occur in any vehicle line. But when the same small component fails in the same way, across multiple model years and mileage ranges, and leads to the same kind of severe damage, that repetition becomes evidence worth examining.

That is exactly what brought my team to the Cummins 6.7L grid heater system.

Let’s dive in.

What’s the Problem with 6.7L Cummins Engine?

At the center of these reports is the intake grid heater assembly used on Ram trucks with the 6.7L Cummins diesel engine, spanning roughly the 2007 through 2024 model years, including newer trucks. The grid heater helps warm incoming air during cold starts, but it relies on a small bolt to secure its electrical connection.

According to owners and mechanics, that bolt can degrade over time due to extreme heat, constant vibration, and, in some cases, corrosion caused by moisture or condensation. When it fails, the consequences can be immediate and severe.

Owners who later experienced engine damage often reported one or more of the following beforehand:

• Sudden rattling, knocking, or grinding noises from the engine
• Check engine lights appearing without clear drivability issues at first
• Diagnostic trouble codes such as P2609 or P0542
• Loss of power or rough engine operation shortly after a warning light
• Engine seizure or failure shortly after unusual noises begin
• Complete engine shutdown requiring towing

What are Owners Experiencing?

Here are three representative complaint excerpts from owners experiencing thrust bearing-related failures:

“My 2023, Ram 2500 truck with a Cummins 6.7L diesel engine has a known defect with the grid heater bolt. This bolt can loosen or break off, falling into the engine and causing catastrophic engine failure. This creates a sudden loss of power, especially dangerous when towing heavy loads at highway speeds. Numerous owners have reported this issue, yet no recall has been issued. I request investigation and action to protect driver safety.” [Source]

“Grid heater nut/bolt has been reported to deteriorate enough to allow the nut to drop into the intake manifold and get sucked into the engine causing catastrophic engine failure. This information comes from shops that have replaced the engines that have had this failure occur”

“Issue is that the on the Diesel intake heater core has a bolt that comes loose from inside the manifold and can fall down into the cylinder and can cause catastrophic failure.”

Is There a Recall?

To date, there has been no recall or formal remedy specifically addressing grid heater bolt failure.

What Can You Do If You Own One of These Trucks?

If you own or are considering buying a Ram 2500 or 3500 with the 6.7L Cummins diesel, there are practical steps you can take:

1. Pay attention to new engine noises, especially rattling or metallic sounds.
2. Scan for diagnostic codes if a check engine light appears.
3. Document all maintenance and repairs, including dealer visits and diagnostic reports.
4. Ask specifically about the grid heater assembly if engine issues arise.
5. Keep records of any warranty denials or repair estimates you receive.
6. Do not delay inspection if symptoms appear—continued operation may worsen damage.

Understanding Your Legal Rights

Depending on your state, repeated engine failure, extended repair delays, or complete engine replacement can implicate:

• Warranty protections
• Lemon law rights
• State consumer protection statutes
• Class action litigation

Each case depends on facts, timing, and repair history. No outcome is guaranteed. But owners are not without options.

Get a Free Case Evaluation

If your Ram truck suffered engine damage that you were told resulted from a grid heater bolt or intake-related failure, you may want to learn more about your options. Lemberg Law is currently reviewing these cases as part of an ongoing class action investigation, while also evaluating individual claims where appropriate.

There is no cost to speak with us. We handle these matters on a contingency-fee basis, which means you do not pay legal fees unless there is a recovery.

If you would like to share your experience, you can contact us to begin that conversation.

About the Author:

Sergei Lemberg is an attorney focusing on consumer law, class actions related to automotive issues, and personal injury litigation. With nearly two decades of experience, his areas of practice include Lemon Law (vehicle defects), Debt Collection Harassment, TCPA (illegal robocalls and texts), Fair Credit Reporting Act, Overtime claims, Personal Injury cases, and Class Actions. He has consistently been recognized as the nation's "most active consumer attorney." In 2020, Mr. Lemberg represented Noah Duguid before the United States Supreme Court in the landmark case Duguid v. Facebook. He is also the author of "Defanging Debt Collectors," a guide that empowers consumers to fight back against debt collectors and prevail, as well as "Lemon Law 101: The Laws That Lemon Dealers Don't Want You to Know."

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