Also known as: ls2, ls3, ls4, ls7, ls9, l76, l77, l92, ly2, ly6, lz1, gen iv small block, 6.2 ls, afm engine, l98, l96
General Motors' fourth-generation small-block V8 — the LS2, LS3 and LS7 in the Corvette, Camaro, G8, Commodore and Caprice, and the truck engines LY2, LY6 and L76 across the GMT900 range. The 5.3 of that range — the LY5 and its LH6, LC9 and LMG siblings — has its own page. Its successor is the LT (Gen V small block) and its predecessor the LS (Gen III small block).
What separates it from the Gen III is cylinder deactivation, and that is where its faults live. Active Fuel Management shuts down four cylinders under light load using collapsible lifters, and those lifters fail — producing a persistent misfire on one cylinder and, if it is left alone, a wiped camshaft lobe beneath it. A load-dependent or wandering misfire on one of these is AFM until proven otherwise. The same system sprays oil at the cylinder walls, and a truck burning oil with no external leak is a pattern rather than a mystery.
The LS7 has a defect of its own and it is the serious one: valve guide wear. The guides wear, the valve stem then does not seat squarely, and a dropped valve destroys the engine. It is specific to that engine and worth a leak-down test on any car carrying one, regardless of how it is running.
And the LS4 is the odd one out — mounted transversely, driving the front wheels in the Impala SS, Monte Carlo SS, Grand Prix GXP and LaCrosse Super. Its accessory drive, exhaust and transmission share nothing with the rest of the family, so a procedure written for a rear-drive LS does not describe it.
L98 on a Holden is this engine; on a 1980s Corvette it is not. GM used the designation twice, twenty years apart — the earlier one is a first-generation 5.7 with tuned-port injection.
⚑ It is a family spanning 4.8 to 7.0 litres, and this catalogue carries it across twenty-one models at 4.8, 5.3, 6.0, 6.2 and 7.0. A figure quoted for the Gen IV LS names one member: the truck 4.8 and the LS7 share an architecture and almost no parts. Establish the displacement and the RPO code before ordering.
Cars fitted with this engine
26 generations, across 8 makes. From the authored catalogue — an absent car means the catalogue has not reached it, not that the engine was never fitted.
Cadillac
Chevrolet
- Monte Carlo Sixth generation 2000–2007
- TrailBlazer First generation (GMT360) 2002–2009
- SSR First generation 2003–2006
- Corvette C6 2005–2013
- Tahoe GMT900 2006–2014
- Suburban GMT900 2006–2014
- Impala Ninth generation (W-body) 2006–2016
- Silverado GMT900 2007–2014
- Avalanche Second generation 2007–2013
- Camaro Fifth generation 2009–2015
- Silverado K2XX 2014–2018
Holden
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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