LMG 5.3L engine: specs, donor vehicles & swap notes
The LMG is a 5.3 L iron-block Generation IV engine built 2007–2014, rated 315–320 hp (Unconfirmed). It came in 7 vehicle applications, including Chevrolet Avalanche, Chevrolet Silverado 1500. Things to know: it has AFM, so an aftermarket cam means a full AFM delete.
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| Spec | Value |
|---|---|
| RPO | LMG |
| Family | Generation IV |
| Years | 2007–2014 |
| Displacement | 5.3 L / 325 ci |
| Horsepower | 315–320 hp (Unconfirmed) |
| Torque | 335–340 lb-ft (Unconfirmed) |
| Bore × stroke | 3.78 × 3.622 in |
| Compression | 9.95:1 |
| Block | iron |
| AFM/DOD | Yes |
| VIN 8th digit | 0 |
| Reluctor | 58x |
| Stock cam | 2007-2009: part 12593207, 193°/193° at 0.050, 0.482/0.482 in lift, 116° LSA, 1-bolt 4x gear (Unconfirmed). AFM Yes. 2010-2014: part 12625436, 196°/201° at 0.050, 0.481/0.481 in lift, 116°+2 LSA, 1-bolt 4x gear (Unconfirmed). AFM Yes. VVT is Unconfirmed. Service-table cam lobe lift is 7.2 mm (0.283 in) intake and exhaust on non-AFM cylinders and 7.33 mm (0.289 in) on AFM cylinders. Valve lift is 12.24 mm intake and exhaust on non-AFM cylinders and 12.46 mm (0.491 in) on AFM cylinders. The AFM lobes are taller, so the lifters have to match the cam. |
| Firing order | 1-8-7-2-6-5-4-3 |
| Oil capacity | 6.0 qt |
| Oil filter | 89017524 / PF48 |
| Spark plug | 12571164 / 41-985 (2007 Tahoe/Suburban; 2008 Silverado 5.3L); 12609877 / 41-985 (2009 Tahoe/Suburban); 12621258 / 41-110 (2010 Silverado, Sierra, and Tahoe/Suburban; 2011 Sierra; 2012 Silverado and Tahoe/Suburban; 2013 Sierra and Yukon/Yukon XL) |
| Plug gap | 0.040 in |
| Head casting | 799, 243 (Unconfirmed) |
- AFM lifter failure (ticking, misfire, cam damage). Fix: Permanently disable AFM using a tuner.
- Excessive oil consumption. Fix: Pro tip: Check oil level every 1,000 miles. Many 5.3 engines consume oil faster than expected.
- Composite intake manifold cracking. Fix: Replace intake manifold and gasket; do not overtighten bolts.
Iron/Alum. heads, AFM, VVT is Unconfirmed, E85-capable
How the LMG differs from the other 5.3 L Gen IV engines
The LMG is one of the eight 5.3 L Gen IV engines we list: LC9, LH6, LH8, LH9, LMF, LMG, LS4, LY5. From our engine table:
- Iron block. Among the 5.3 L Gen IV engines, the LMG shares it with the LMF, LY5; the LC9, LH6, LH8, LH9, LS4 are aluminum.
- AFM (cylinder deactivation): yes. Same as the LC9, LH6, LS4, LY5; the LH8, LH9, LMF don't.
- Compression 9.95:1. The pistons and chamber are matched to this ratio, so check a replacement piston or head before you mix it in.
- Rated 315–320 hp and 335–340 lb-ft (Unconfirmed). Identify the engine from the RPO sticker and the VIN digit, not from this power number.
- VVT is Unconfirmed. Check the timing cover (a VVT cover carries the phaser solenoid) before you order cam parts.
- Built flex-fuel from the factory, iron block, VIN 0. Swapping an LMG onto E85 means a flex-fuel tune. Whether that truck has a hard ethanol sensor is Unconfirmed.
- Built 2007–2014.
Swapping the LMG: what to plan for
- Flex fuel. The LMG is the iron AFM 5.3, VIN 0, and the trucks checked list it as flexible fuel. Confirm the RPO, then set the tune for that truck's fuel calibration. A hard ethanol sensor is Unconfirmed. Look at the truck before you add a sensor or leave one out. More: LC9 flex-fuel years.
- Computer: the LMG has a 58x crank. An E38 or E67 matches it; a 0411/P59 also needs a 58x-to-24x converter box and its own sensor and knock-sensor wiring. Throttle and wiring have to suit the computer too. More: how to wire your LS (the full checklist for your engine and computer).
- AFM: a stock-cam LMG can have AFM turned off in the tune; an aftermarket cam means a full AFM delete (non-AFM lifters and trays, a non-AFM valley cover, the tune). More: LS cam swap guide.
- VVT is Unconfirmed. Check the timing cover for a phaser solenoid before you order a cam or a water pump. A VVT cover needs a pump that clears it. More: accessory drives.
- From a truck or SUV (Chevrolet Avalanche, Chevrolet Silverado 1500, Chevrolet Suburban 1500, Chevrolet Tahoe and 3 more): truck accessory drive spacing (the farthest forward of the three), and the factory truck oil pan hangs low; most car swaps need a swap pan. More: accessory drive spacing · oil pans.
Refresh parts for the LMG
From our Gen IV refresh list, the parts that are specific to the LMG. Seals, gaskets and the upgrades worth doing on any Gen IV with the engine out are in the full refresh list, next to every torque spec.
| Part | GM part # | Why for this engine |
|---|---|---|
| LSXceleration Gen IV LS knock sensor 28-23730 | 28-23730 | The LMG has its knock sensors on the side of the block. |
| GM Gen IV camshaft position sensor 12591720 (58x engines) | 12591720 | 58x LMG: the cam sensor lives in the front cover. |
| Chevrolet Performance 58x crankshaft position sensor 12703627 | 12703627 | 58x LMG: the crank sensor is behind the starter. |
| GM oil pressure screen/filter 12585328 (AFM valley cover) | 12585328 | On 2007-and-later AFM V8s: Clogged screen starves the sender and causes false low-pressure codes on AFM engines. |
| Genuine GM 12610141 valley cover gasket (LS2/LS3, no AFM/DOD) | 12610141 | Needed if you delete AFM on the LMG with a non-AFM valley cover. |
What real 5.3 L Gen IV truck tunes run
What these settings look like in the 192 naturally aspirated pump-gas tunes for 5.3 L engines on an E38 computer in our tune library (as of 2026-10-15). These files do not record which 5.3 L it was (LC9, LMG, LY5 or another) or which vehicle, so this is the 5.3 L Gen IV (E38) naturally aspirated pool, not one RPO. Most files have no stock or aftermarket cam label, so stock and aftermarket stay in one table. The ranges are wide because every cam and build in that pool is included. Use them to spot a value that is far outside what works, not as your numbers.
| Setting | Range | Median | Tunes |
|---|---|---|---|
| Hot idle target | 525 rpm to 800 rpm | 535 rpm | 192 (middle 80%) |
| Warm idle airflow, in gear | 6.0 g/s to 10.5 g/s | 6.8 g/s | 192 (middle 80%) |
| Idle spark (around 800 rpm) | 16° to 20° | 18° | 191 (middle 80%) |
| Power enrichment (PE) lambda | 0.76 to 0.85 | 0.78 | 184 (middle 80%) |
| WOT spark at 5,000 rpm, about 0.9 g/cyl | 13.0° to 22.5° | 14.5° | 192 (middle 80%) |
For starting values matched to your LMG's cam, injectors and fuel, use the turn-on tune builder. Always finish on a dyno, and read our safe tuning limits before any wide-open pass.
Donor vehicles with the LMG
Where to find an LMG at the junkyard: 7 vehicle applications below. Confirm it from the RPO sticker in the glovebox or the 8th VIN digit (for the LMG: 0).
| Vehicle | Years |
|---|---|
| Chevrolet Avalanche | 2007–2013 |
| Chevrolet Silverado 1500 | 2007–2013 |
| Chevrolet Suburban 1500 | 2007–2014 |
| Chevrolet Tahoe | 2007–2014 |
| GMC Sierra 1500 | 2007–2013 |
| GMC Yukon | 2007–2014 |
| GMC Yukon XL 1500 | 2007–2014 |
Buying a used LMG
A used LMG has no single part number, so this page does not link a search. Confirm the engine from the RPO sticker or the 8th VIN digit (for the LMG: 0) before you buy.