Active Fuel Management from General Motors
Thank you for your interest in GM hydraulic lifter information. The GM LS engines all share the standard GM roller lifter. The lifter was developed in the GenII LT1 and Vortec Engines. This HL-2148 is what most people commonly refer to as the LS7 lifter.
In the engines equipped with AFM, the HL-7011 controls the de-activated cylinders. For instance, this HL-7011WT is known as the HL178 hydraulic lifter. Today’s GM engines are DFM Dynamic Fuel Management. The DFM is different from AFM.
Lifter failure is the fuse of your engine
The spring on the top of the lifter body is designed by General Motors as the fuse of the valvetrain. If the vehicle computer activates the VLOM at the wrong ignition valve timing, the spring is designed to collapse. This saves the rest of the engine from damage. As long as the tolerances of the valves, valve springs, pistons, rocker arms, pushrods are to the manufacturer’s original specifications. Here at Elgin Industries, we offer auto parts equivalent to OEM interchange.
Intermittent ground fault with your vehicle PCM is the most common cause for lifter failure. The collapsed spring is a mechanical fuse designed to compensate for electrical failure. To prevent the issue from reoccurring, you should further inspect the electrical system. This includes GenIII, GenIV, and GenV LS engines.
Replacement auto parts for the AFM LS engine
When replacing the lifters, be sure to change a few other parts too. Lifter guides can fail from polymer fatigue. The worn guides can allow the lifter to spin in the bore causing engine failure. Elgin Industries’ lifter guides are OE. They are the same as you would buy from the parts department at your new car & truck dealership.
Although we do not supply the VLOM, or the matching VLOM filter, these should also be replaced with the new lifters. A certified technician could also test your Variable Lift Oil Manifold. This applies to any AFM Chevrolet, GMC, Cadillac, or GM Product.
If the cam was damaged, you should be certain the new AFM camshaft is correct for the vehicle VIN. Some vehicle owners are choosing a complete AFM delete kit from reputable suppliers. We do not offer a complete kit, however, we do offer many parts. In addition we offer timing sets for one bolt and three bolt camshaft conversions. More of Elgin Industries LS engine parts are available in our online catalog.
Your resource for quality Engine & Chassis parts
In conclusion, the overall design of the pushrod V8 engine continues to prove reliable. After all, it’s compact size has found it’s way into a variety of light and medium duty truck platforms. Parcel package delivery transports, pump & power generation, and defense contract vehicles all share LS power. Elgin offers a full line of engine and chassis components. How can we help you?
Elgin Industries continues to supply engine & chassis parts for global and domestic markets. As a Tier One original equipment manufacturer, we also supply aftermarket auto parts. Similarly, you can find our parts from world wide wholesalers and regional distribution warehouses. In addition, we supply production engine remanufacturers, as well as machine shop engine rebuilders. Above all, we’d be happy to connect you with a distributor if you need help locating Elgin parts.
Please feel free to contact us today!
sales@elginind.com USA & Canada
worldtrade@elginind.com outside the USA