Most Common GM LS2 Engine Problems

The GM LS engines are nearly synonymous with reliability, and the LS2 is no exception. However, all engines are prone to occasional problems. The 6.0L V8 LS2 is no exception there, either. Ultimately, it’s an incredibly reliable engine but it is not completely bulletproof. Some of the more common GM LS2 engine problems include oil starvation, rocker arm bearings, and the harmonic balancer.

LS2 6.0 V8 Issues

• Oil starvation
• Rocker arm bearings
• Harmonic balancer

To expand on the introduction, these are some of the most common issues. That doesn’t mean they’re truly common in that they affect a large percentage of LS2 engines. However, when problems do occur these are some of the most common areas.

In the next few sections, I will expand on the above faults and circle back to overall reliability at the end. Again, it’s important to note that the GM LS engines are incredibly reliable and nearly bulletproof engines. Due to their popularity, the few flaws are also well understood and effective, long-term solutions exist.

1) Oil Starvation

LS2 oil starvation isn’t an issue that should concern most. However, the engine uses wet sump rather than dry sump oiling. Wet sump oil systems are simple but they are not ideal for tracking or sustained high-G cornering. The LS2 oiling system also suffers some issues on high-revving builds as it tends to run into cavitation above 6,500rpm.

If you plan to track, do canyon drives with long, high-speed corners, or anything of the likes then it’s a good idea to add an extra 1L of oil to the engine. That’s the simple and cheap route to reduce the chance of oil starvation. It’s not a bulletproof solution, though. Even those who added extra oil have still run into serious engine problems or complete failure due to oil starvation.

Again, this isn’t really a true design flaw or issue with the engine. Wet sump oiling just isn’t an ideal setup for cars like the Corvette. It’s something to address if you plan on high-power builds, tracking, etc. Fortunately, there are plenty of solutions to improve the LS2 oiling system.

LS2 Oiling Upgrades

Discussing oiling upgrades for the 6.0L LS2 could be an entire article or two of its own, so this section is meant to be a basic starting point. Upgrading the oil pan is a simple option and a well-designed pan can help reduce oil starvation issues. It won’t completely eliminate the possibility, though.

Going a step further, an accusump is a great addition to the factory LS2 oiling. Accusumps are oil accumulators that store pressurized oil (much like dry sump systems) and release oil back into the engine as oil pressures drop. These accusumps also help with pre-oiling on start-ups which can already help extend engine life.

The most bulletproof option is fully converting to dry-sump oiling, but this can be very expensive. Parts alone will run in the $2,500-4,000 ballpark and labor will add quite a bit more if you aren’t DIY’ing the job. It’s overkill unless you’re doing a crazy power build or tracking the car aggressively with R-compound tires and power mods.

2) Rocker Arm Bearing Issues

Problems with LS2 rocker arm bearings is a little more technical. It’s an issue that became more and more prevalent as the LS engines aged. The OEM rockers have a weak trunion design that allows the needle bearings to escape into the oil galleys. The design also doesn’t allow the needle bearings to rotate around the pivot of the trunion. This can cause uneven wear of the bearings and potentially lead to failure.

Rocker arm bearing problems are common on higher mileage LS2 engines. However, it’s still not a truly common failure. That said, the weakness can be more serious with performance cams, stronger valve springs, and sustained high RPM driving. As such, if you’re in the cylinder head it’s a good idea to address the rocker arms.

Replacing the rocker arm trunion and bearings is inexpensive when it comes to parts costs. Even upgrading the rocker arms altogether is cheap if you’re in the cylinder head anyway. LS2 rocker arm upgrade kits are a great option to improve the reliability of the 6.0 V8.

3) LS2 Harmonic Balancer Problems

This list of LS2 engine problems is not in any specific order. If it were, harmonic balancer issues would likely take the #1 spot for the most common. The harmonic balancer – also known as a crankshaft damper – absorbs vibrations from the crankshaft. Very few engines, including a 90° V8, are harmonically balanced.

Vibrations would be too severe and lead to numerous other engine problems without the use of a harmonic balancer. Unfortunately, on the LS2 it’s known to begin wobbling and break down over time. In very extreme cases, it may actually warp the crankshaft and lead to complete engine failure or the need for an engine rebuild.

If your LS2 has excessive vibrations, rattling or knocking noises, or similar symptoms then its often the harmonic balancer beginning to fail. The good news is, issues with the balancer rarely cause any other failures as long as its caught in time. There are plenty of quality upgrades like this ATI Super Damper.

GM LS2 Reliability

As mentioned a few times throughout, the LS2 is a reliable engine. Oil starvation can be a serious problem, but it’s generally only a concern for those pushing the limits of the engine. If you’re tracking the LS, building a high-power or high-revving engine, or anything of the likes then oil starvation is something to consider.

Rocker arm bearings are another issue that isn’t overly common or concerning. However, upgraded cams and valve springs can put more stress on the weak rocker arm bearings and trunions. If you’re in the cylinder head for these upgrades then it’s best to address the rocker arms. It’s a cheap upgrade that improves upon the already reliable LS2.

Lastly, LS2 harmonic balancer problems are one of, if not, the most common problems. Plenty of upgrades and long-term solutions exist, so keep an eye on the harmonic balancer and upgrade when the time comes.

Ultimately, the LS2 offers excellent reliability but still has its share of shortcomings and design flaws. Keep up with maintenance, use quality oils, and fix issues in a timely manner if and when they occur. Do all this and the LS2 is an incredible engine that can live on for hundreds of thousands of miles.