This is an engine specification guide for General Motors’ fifth-generation L84 engine that launched in 2018 for use in the Chevrolet Silverado 1500 and GMC Sierra 1500. It is commonly referred to as an EcoTec3 5.3L engine and replaces the L83.
Compared to its predecessor the L83, the L84 has a different valley cover, centered water pump location, and exhaust system. By centering the water pump, it allows Gen. 4 high-mount air-conditioning and power steering pumps to be added when the engine is swapped into older vehicles. With changes to the Brake Controller, the vacuum pump and lines are no longer required
It continues to incorporate Variable Valve Timing (VVT). The engine also uses direct injection, which shoots fuel directly into the combustion chamber instead of the intake runner.
As before, it has flex fuel capability. It’s also a mild-hybrid with start/stop technology.
Versus the previous L83 or the current L82, the L84 (new for 2019) replaces AFM with the more advanced Dynamic Fuel Management (DFM) system. DFM has cylinder deactivation lifters on all eight cylinders rather than just four. DFM has 17 modes of operation and can run on as little as one cylinder at a time. Because the system is torque based, it uses just the right amount of cylinders to meet demand with seamless transitions.
The information listed here is for a stock engine.
(Summit Racing’s Brian Nutter and Paul Spurlock contributed to this article.)
Chevy L84 Engine Specs
L84 Performance Specifications
| Engine Ratings | |
|---|---|
| Compression Ratio | 11:1 |
| Horsepower Rating | 355 hp @ 5,600 rpm |
| Torque Rating | 383 ft.-lbs. @ 4,100 rpm |
L84 Application Information
| Year | Make | Model |
|---|---|---|
| 2019-present | Chevrolet | Silverado |
| 2019-present | GMC | Sierra |
L84 Engine Block Specs
| L84 Block Specs | |
|---|---|
| Part Number | 12620290 |
| Material | 319-T7 Aluminum |
| Displacement | 5.3L / 325 c.i.d. |
| Bore Dia. | 3.780 in. |
| Stroke | 3.622 in. |
| Deck Height | 9.240 in. |
| Bore Spacing | 4.400 in. |
| Thrust Bearing Location | #3 Main, 1/2 thrust |
| Main Cap Style | 6-Bolt |
| Main Housing Bore Dia. | 2.751 in. |
| Cam Housing Bore Dia. | Bore 1/5 = 2.346 in. Bore 2/4 = 2.326 in. Bore 3 = 2.307 in. |
| Cam-to-Crank Centerline | 4.914 in. |
L84 Rotating Assembly
| L84 Rotating Assembly Specs | |
|---|---|
| Piston Material | Hypereutectic Cast Aluminum Alloy |
| Piston Style | Domed (with reliefs for the exhaust valve and direct injector) |
| Piston Volume | 0cc (net) |
| Wrist Pin Dia. | 0.9431 in. (full floating) |
| Connecting Rod Material | Powdered Metal |
| Connecting Rod Style | I-Beam |
| Connecting Rod Length | 6.098 in. |
| Connecting Rod Housing Bore | 2.225 in. |
| Connecting Rod Bolts | M9 x 1 x 43 |
| Connecting Rod Part Number | 12607475 |
| Crankshaft Material | Cast Iron |
| Crankshaft Part Number (Wet Sump) | 12619781 |
| Crankshaft Main Journal Dia. | 2.559 in. |
| Crankshaft Rod Journal Dia. | 2.100 in. |
| Reluctor Wheel | 58X |
| Harmonic Balancer | Iron |
L84 Cylinder Heads
| L84 Cylinder Head Specs | |
|---|---|
| Casting Number | 12620214 |
| Material | 319-T7 Aluminum |
| Combustion Chamber Volume | 57.6cc |
| Intake Port Shape | Rectangle |
| Intake Runner Volume | 248cc |
| Exhaust Port Shape | Flat Oval |
| Exhaust Runner Volume | 102cc |
| Cylinder Head Bolt Style | Torque to Yield (TTY) |
| Cylinder Head Bolt Size | (10) M12 x 1.75, M8 corner bolts |
L84 Camshafts
| L84 Cam Specs | |
|---|---|
| Part Number | 12619823 |
| Duration @ .050 in. (int./exh.)* | -- |
| Valve Lift (int./exh.)* | -- |
| Lobe Separation Angle* | -- |
| Cam Gear Attachment | 1-Bolt |
| Cam Gear Poles | 4X |
| Active Fuel Management (AFM) | Yes |
| Variable Valve Timing (VVT) | Yes |
| *Specifications currently unavailable. | |
L84 Valvetrain
| L84 Valvetrain Specs | |
|---|---|
| Lifter Style | Hydraulic Roller |
| Lifter Link Style | Plastic Lifter Tray |
| Lifter Body Diameter | 0.842 in. |
| Pushrod Dimensions | 7.85 in. (long) x 0.342 (dia.) |
| Rocker Arm Mounting Style | Pedestal |
| Rocker Arm Style | Die-Cast, Roller Fulcrum |
| Rocker Ratio | 1.8 |
| Rocker Offset | None |
| Valve Spring Style | Beehive |
| Valve Spring Color | Natural |
| Intake Valve Angle | 12.5° / Splayed 2.61° |
| Exhaust Valve Angle | 12.0° / Splayed 2.38° |
| Intake Valve Material | Steel, Solid Stem |
| Intake Valve Dia. | 1.928 in. |
| Exhaust Valve Material | Steel, Sold Stem |
| Exhaust Valve Dia. | 1.556 in. |
| Timing Chain Guide Style | Spring-Loaded Tensioner |
L84 Specs
| L84 Intake, Throttle Body, Fuel Injector Specs & More | |
|---|---|
| Intake Manifold | Truck Style |
| Throttle Body | 80mm, 4-Bolt |
| Throttle Control | Electronic (Drive-by-Wire) |
| Fuel Injector P/N* | -- |
| Fuel Injector Flow* | -- |
| Flex Fuel Capable (E-85) | Yes |
| Computer* | -- |
| Crankshaft Reluctor Ring | 58x |
| Camshaft Sensor Location | Timing Cover |
| Oil Pan | Varies by Application |
| Oil Pump | Variable Displacement |
| *Specifications currently unavailable. | |
This new engine is sweet, especially the quiet cast factory headers.
I work with a guy that has a 2015 and the lifters froze up and ruined the motor. I hope they have fixed this issue. Not a fan of AFM. Doesn’t get any better fuel mileage. To bad the 5.3 is a good engine and they ruin it with this. Nothing but problems. And very expensive to fix.
How can i get a standalone wireing harness for my L84 LT 5.3 so i can put it in a 1980 Camaro
Thanks ray m
I get substantially better highway mileage with my 2018 silverado with the 5.3L AFM engine. Even with my 4WD system i can routinely obtain 22-23MPG so i have no idea where you are coming from. That said if you are so heavy footed that the 4CYL mode never turns on you will get regular mileage, maybe 20MPG highway. This system does nothing really for city driving.
It says AFM = Yes when it should say DFM right? Totally different system than AFM. If I’m not mistaken, AFM simply changes from 8 to 4 and vice versa. DFM has 17 different modes cycled in 125 millisecond increments. Both systems are crap, but there is a distinction and specific to the L84 from the L82/L83.
my 2021 gmc sierra 1500 does NOT have the variable vane oil pump wiring harness on the front timing cover. It is the L84 engine / flex fuel . I can text you a pic…if you would like. It is considered a “work truck” by GMC. My question then is …….. would it have a conventional oil pump then ? Maybe I will check with GM parts and,using my vin number….compare it to a KNOWN variable vane vin number..
2018 Silverado LTZ Z71 1500, Bought & Financed through Carvana delivered to home Kemah Texas on 2/10/24 w/ $6K cash down and payments, 66,422 Miles. Drove TEN Days 400 miles total back n forth to work, 2/20/24 leaving work Check engine light came on-Vibrations shut it down called warranty towed to shop. As of Today 4/3/24 the truck has been in the shop for 42 Days… Warranty chose to have shop replace motor vs tear down motor for cost. Installing 2020 re-man. What the heck is wrong with these chevy motors / issues now that I’m looking into this since it’s happened to me?? Chevy Man but WTF… Bryan, Kemah Texas
i hated that 4 cylinder mode. i bought a plug in bypass to eliminate it. now i have v8 all the time. best 100 bucks i ever spent.