The Truth About GM's AFM/DOD System on LS & Gen V LT Engines – And Why an AFM/DOD Conversion Kit is the Real Fix

When it comes to GM’s modern V8 lineup, enthusiasts and daily drivers alike know the LS and Gen V LT platforms are some of the most capable engines ever built. But ask any gearhead who’s torn one apart, and you’ll hear the same gripe: Active Fuel Management (AFM) and Displacement on Demand (DOD). GM’s attempt at squeezing extra MPG out of performance engines has turned into one of the most notorious weak spots in otherwise bulletproof builds.

At Michigan Motorsports, we’ve seen it firsthand. That’s why our AFM/DOD Converison Kits have become one of the most effective solutions for builders who want to get rid of the headaches, protect their investment, and unlock the full potential of their LS or LT.

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What is AFM/DOD?

AFM (Active Fuel Management), also called DOD (Displacement on Demand), is GM’s cylinder deactivation technology found in many 2005+ LS and Gen V LT V8 engines. The idea was simple: under light load, the system shuts down half the cylinders — essentially turning a V8 into a V4 — in order to boost fuel economy.

On paper, that sounds great. In the real world, it means GM’s performance engines are saddled with complex lifters, oil control valves, and additional hardware designed to deactivate cylinders on the fly. That complexity is exactly what leads to problems.

Why Did GM Use AFM/DOD?

The short answer: fuel efficiency standards. In the mid-2000s, automakers were under pressure to meet stricter emissions and MPG requirements. GM chose AFM/DOD as a way to improve fleet-wide fuel economy numbers without ditching the V8 entirely.

Unfortunately, what worked for the business clipboard hasn’t worked so well for car owners. Instead of lasting reliability, drivers are now faced with ticking lifters, oil consumption issues, and expensive repair bills.

Common Failures of AFM/DOD

Anyone who’s worked on an LS or Gen V LT with AFM/DOD knows the weak points:

• Collapsed Lifters – The most notorious failure. Once a lifter collapses, it often wipes out a camshaft lobe in the process.

• Oil Consumption – AFM lifters and pressure relief valves create oil control issues, leading to excessive oil burning.

• Top-End Noise – Many owners complain of ticking or knocking sounds that trace back to AFM lifters and hardware.

• Premature Wear – The added complexity of the system leads to long-term reliability problems compared to non-AFM engines.

The Michigan Motorsports Solution: AFM/DOD Conversion Kits

This is where Michigan Motorsports steps in. Our AFM/DOD Delete Kits are engineered to completely remove the failure-prone system, giving your engine the reliability and performance it is capable of. The foundation of our AFM/DOD Conversion kits start with replacing the failure prone AFM/DOD lifters with Delphi LS7 Lifters and all necessary components to eliminate the AFM/DOD system.

When you install one of our conversion kits, you’re not just preventing common failures — you’re building a stronger, more powerful engine. By removing the extra complexity and going back to a true V8 configuration, you restore oiling efficiency, eliminate lifter collapse issues, and create a stronger foundation for future upgrades like camshafts, cylinder heads, and forced induction.

Note: When installing a AFM/DOD delete kit, you will also need replace the standard AFM/DOD camshaft with a NON- AFM/DOD camshaft. Michigan Motorsports offers many cam replacement options from stock NON- AFM/DOD cams, truck cams, all the way up to full race camshaft options. Once the conversion is done you will also need to have the AFM/DOD system turned off in the vehicles ECU and have it tuned if switching to a non-stock camshaft.

Why Builders Choose Michigan Motorsports

• Proven Reliability – Our conversion kits are built using the same high-quality components trusted by performance shops nationwide.

• Performance Gains – Eliminate parasitic losses from AFM/DOD and free up horsepower that may be left on the table.

• Long-Term Confidence – No more lifter tick, no more oil consumption nightmares, and no more wondering when your AFM system will fail.

For anyone running an LS or Gen V LT with AFM/DOD, the smartest move isn’t waiting for failure — it’s deleting the system before it fails.

Ready to Delete AFM/DOD From Your LS or LT?

If you’re tired of the factories “MPG over horsepower” compromise, it’s time to fix it for good. At Michigan Motorsports, our AFM/DOD Conversion Kits give your engine the reliability, performance, and power it was meant to have.

Take back control of your LS or Gen V LT Engine – and built it the way you want!