Jump to content

2016 silverado 5.3 v8


Recommended Posts

You shouldn't be hearing your lifters, they are hydraulic - if you are hearing your lifters, there is a problem. 

 

You could be hearing your injectors, they are much louder than what people are accustomed to in the sense that modern engines use direct injection. 

Link to comment
Share on other sites

This might be fun to read through:

 

How to Delete or Disable Active Fuel Management (AFM) on GM Engines

Posted by Brian Nutter on November 30, 2017 at 4:37 pm
LS-Engine-on-Stand-1024x760.jpg

(Image/Summit Racing)

Active Fuel Management (AFM) is a trademarked General Motors technology that improves gas mileage by shutting down half of the cylinders under light-load conditions to reduce fuel consumption. It is also known as Displacement on Demand (DoD) or cylinder deactivation.

How Does AFM Affect Performance?

AFM is good for gas mileage and can be 5-7 percent more fuel-efficient under certain conditions.

So Why Turn it Off?

There are a few reasons:

  1. Many people find the four-cylinder sound annoying if their vehicle is equipped with a louder aftermarket exhaust.
  2. Some drivers want V8 power under their foot at all times.
  3. AFM lifters have a history of failing and oil consumption can be a problem.

How to Delete or Disable AFM on GM/Chevy Engines

There are two ways to disable or delete Active Fuel Management on your GM or Chevy Gen IV LS or LS-based Vortec engine—one is to install an AFM Disabler, and the second is to install an AFM Delete Kit. Here’s what you need to know:

1. Install an AFM Delete Kit

An AFM Delete Kit is recommended when an AFM lifter fails or when doing performance upgrades. It replaces the AFM components with standard parts.

When installing an AFM delete kit:

  • You MUST upgrade to a non-AFM camshaft because the cam lobes in the four AFM cylinders are ground differently. The engine will have 25 less pounds of compression in those four cylinders which can result in a misfire code.
  • You will need to turn off the AFM system using a computer programmer or custom tuning.
  • It’s a little more work, but it’s recommended that you plug the pressure relief valve in the oil pan.
  • It is also recommended that you switch to a standard-volume oil pump.

2. Install an AFM Disabler

An AFM Disabler is an electronic device that plugs into the OBD-II port, under the dashboard. It prevents the computer from switching over to four-cylinder mode. It’s a simple and effective way to turn off the AFM system and provides the added bonus of improving exhaust sound.

NOTE: A disabler device should ONLY be used if the valvetrain is in good working order.

Engines with AFM use a high-volume oil pump. When you eliminate the AFM system, the extra oil is no longer needed. Excess oil will be pushed out of the pressure relief valve into the oil pan. This will spray oil on the bottom of the cylinder walls which can cause oil burning, especially in high-rpm engines.

Which Option is Best—a Disabler or Delete Kit?

As long as a lifter hasn’t started to fail, you can get by with a less-expensive disabler as preventative maintenance. If a lifter has already started to fail, an AFM delete kit and non-AFM components are the way to go.

NOTE: If you were in a situation where you’ve installed the AFM delete kit, but don’t have access to a programmera disabler can still be a viable option. To do this, you need to leave the AFM solenoid pack connected to ensure no codes are thrown. You can reuse the original valley cover OR use a non-AFM valley cover, leave the harness connected, and tuck the solenoid pack away.

GM/Chevy Engines Factory-Equipped with AFM

 

Engine Displacement RPO Code
5.3L LY5 LC9 LH6 LMG LS4
6.0L L76 L77 LFA LZ1  
6.2L L94 L99      

How to Identify AFM Engine Components

The AFM system can be identified by its components. Look for the following:

1. Valley Cover

The AFM cover is called the Lifter Oil Manifold Assembly (LOMA). It’s ribbed with solenoids on the underside. It also has an electrical connector on the back. (Non-AFM engines have a smooth cover.)

LS - Lifter Oil Manifold Assembly (LOMA)

2. Engine Block

All Gen IV engine blocks have AFM towers and oil passages cast in. However, they are only functional on engines that used AFM.

LS - AFM Towers

3. Lifters

AFM engines use special lifters for cylinders 1, 4, 6, and 7. They are taller and have special oil holes.

LS - AFM lifters labeled

Engines with AFM also use a special camshaft, a high-volume oil pump, and a pressure relief valve in the oil pan.

3. Oil Pressure Relief Valve

This valve is located on the oil pan rail and prevents excessive oil pressure from negatively impacting the AFM components. The original version sprayed oil on the cylinder walls and increased oil consumption. In 2010, GM added a deflector (p/n) NAL-12639759 to redirect in into the pan. This should be added to your earlier model if you experience oil consumption.

The valve itself is part number W0133-2574213. If you want to delete it entirely, it’s a M14 x 1.5 pipe plug or you could use the Improved Racing plug p/n IRP-814-M14-Kit.

How Active Fuel Management (AFM) Works

How Active Fuel Management (AFM) Works

(Image/GM Media)

When engine load is low:

  1. The computer sends a signal to the LOMA.
  2. The LOMA solenoids open.
  3. Oil flows to the special lifters through the AFM towers.
  4. The oil collapses the plunger inside the lifter.
  5. The collapsed lifters will not engage the pushrods and both valves remain closed.

Since no air can get in or out, four cylinders provide no power. The engine is running on only four cylinders.

The AFM cylinders are opposite of one another in the firing order. In four-cylinder mode, they act like air springs and allow for smooth operation.

As engine load increases:

  1. The computer sends a signal to the LOMA.
  2. The LOMA solenoids close.
  3. Oil bleeds off the lifters.
  4. The lifters return to normal operation.

All eight cylinders are now powering the engine.

NOTE: Some parts are not legal for use in California or other states with similar laws/regulations.

NOTE: You can find engine specs and detailed engine upgrade advice for every LS and LS-based Vortec truck engine in one place: The Definitive Guide to LS Engine Specs and LS Engine Upgrades.

 
 
 
Tags: Active Fuel Management, AFM, AFM delete kit, AFM disabler, cylinder deactivation, LS engines
 
 
Author: Brian NutterAfter a stint in the U.S. Air Force, Brian Nutter studied at the Houston, TX-based School of Automotive Machinists in 1997. The early part of his automotive career included working for engine builders Scott Shafiroff and C.J. Batten, followed by several years developing performance pistons at Wiseco Piston Co. Today, Brian develops performance parts for Summit Racing Equipment and is a regular OnAllCylinders contributor. For fun, he runs his 427-powered C5 Z06 in ECTA land-speed racing, at OPTIMA® street car events, and at a mix of autocross, drag racing, and track days.
 

 

  • Like 1
Link to comment
Share on other sites

  • 2 weeks later...
On 2/17/2021 at 9:22 PM, Frankielozano214 said:

I paid some youngster from Fort Worth that worked at the Chevy house, he charged me 500$ for labor plus the fluids (let’s say another 100$) he did it over the weekend at his house. I supplied all my parts, at the time I didn’t want to change the stall if I got a different cam, so I kept the cam close to oem/ factory specs without the afm/dod. Lifter 7# collapsed 2 months after putting 5000$ down on it so money was very tight at the time and didn’t have warranty on it 

I'm guessing you had to get it tuned after the cam install?

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Forum Statistics

    247.6k
    Total Topics
    2.6m
    Total Posts
  • Member Statistics

    336,418
    Total Members
    8,960
    Most Online
    DumbleJum
    Newest Member
    DumbleJum
    Joined
  • Who's Online   3 Members, 0 Anonymous, 450 Guests (See full list)



×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.