Thicker Viscosity oil for GM ENGINES ???

A dealer bulletin obtained by GM-Trucks forum users, all affected units (MY2021-2024) are currently up for recall, including those in the inventory units. While the dealer bulletin only contains instructions for the dealers that will work on the trucks, GM has confirmed in a statement that it will be issuing a voluntary recall "to address this matter as quickly as possible."

There's A Remedy For Those That Pass Dealer Inspections

For the uninitiated, the L87 V8's woes lie in the connecting rod and/or crankshaft components in affected vehicles having unspecified manufacturing defects. When these components fail, it could lead to loss of propulsion or complete engine failure, which can be hazardous or even life-threatening if they occur while in transit. We've found several cases of this issue before, with some instances happening while on the highway, while others reportedly bombing as early as 4 miles.

2:GM has provided a remedy for the problem, although it's incomplete for now. The recalled vehicles will be checked by the dealers for diagnostic trouble code P0016. If it's not set, the vehicle in question passes the inspection but will have its oil replaced by 0W-40 high viscosity oil (replacing the former 0W-20). It will also be given a new oil filter and oil fill cap that reflects the change, as well as a section in the owner's manual for the new oil type. According to the documents shared, the thicker oil "offers an increased further level of protection."

Engine Replacements Could Happen, But...

On the other hand, those vehicles that will not pass the inspection will be "quarantined" and should not be sold/delivered to the customer. It's unclear what will happen to these vehicles, with the documents only stating that "Additional information will be provided by General Motors in the near future."

Edited by steve(ill) - 28 Apr 2025 at 4:31pm

V8's woes lie in the connecting rod and/or crankshaft components in affected vehicles having unspecified manufacturing defects

Seems recall is on the 6.2 Gas V8 engines , not the 6.0 or other engines , 
to meet millage specs the light weight oil was the new grade to reduce friction , 
The old idea of heavy oil for longer life has changed in new engines .
10/30 for many years and now 0/20 seems to be the grade called for 

THICKER oil is a good thing... but thats NOT what the complain says...

I heard they tend to break a rod and depending on position of things can lock engine. Happened to me 47 yrs ago when a 327 broke a rod bolt and came apart. Instant lock at 110 and the torque converter takes a while to decouple so rear tires sliding. Glad it was daylight and sober.