General Motors has once more adjusted its oil recommendation for vehicles equipped with the 6.2-liter L87 V-8 engine, currently under federal investigation for potential catastrophic failure. The latest guidance, reported by GM Authority and confirmed by GM to Car and Driver, directs dealerships to use Mobil 1 FS 0W-40 instead of the previously recommended Mobil 1 Supercar 0W-40.
Recall History and Previous Fixes
This marks the second oil-related change since the engine’s recall was expanded in April 2025, impacting nearly 600,000 trucks and SUVs. The initial recall, triggered by a National Highway Traffic Safety Administration (NHTSA) investigation, initially proposed switching from the standard 0W-20 oil to the thicker Mobil 1 Supercar 0W-40 as a preventative measure against engine failure.
The repeated adjustments highlight the complexities of addressing a serious mechanical issue in mass-produced vehicles. Early solutions can be refined or altered as more data becomes available, or in this case, as practical constraints emerge.
The Reason for the Latest Change
According to a GM representative, the shift to Mobil 1 FS 0W-40 is driven by supply chain realities. The primary factors are cost and availability, with GM instructing dealerships to switch to the more accessible oil once existing Supercar inventory is depleted.
The move appears to be a pragmatic one, as both oils meet the necessary performance criteria for the recall remedy. The heavier weight of the 0W-40 formulation already addresses the original concerns regarding engine stress and potential failure.
What This Means for Owners
The new directive applies specifically to vehicles that have been inspected by dealers and determined not to require engine replacement. Owners should ensure their service technicians adhere to the latest guidance when performing oil changes.
This situation underscores the importance of staying informed about recalls and manufacturer updates, as recommendations can evolve over time, even after initial fixes are implemented.
The ongoing investigation and multiple adjustments to the oil recommendation raise questions about the long-term durability of the L87 engine and GM’s handling of the issue. The latest change is a cost-effective solution for GM, but doesn’t alter the core mechanical concerns that triggered the recall in the first place.
