Known Issues Preview
⚠️ High RiskEngine
AFM Lifter Failure
GM's Active Fuel Management system deactivates 4 of 8 cylinders at highway speeds to save fuel. The collapsible lifters that enable this feature fail at alarming rates, sending metal debris through the entire engine and often destroying the camshaft. Failures have been documented as early as 6,500 miles on brand new trucks. The 2018 5.3L V8 is among the most affected engines. Once a lifter fails the damage is typically catastrophic and many owners disable AFM after repair to prevent recurrence.
Estimated Repair Cost
$2,000 to $7,000
1,800+
owner complaints
⚠️ Medium RiskDrivetrain
8 Speed Transmission Shudder
The 8 speed automatic transmission in the 2018 Silverado is known for shuddering and vibrating at highway speeds, hesitating between gears, and torque converter failures after 80,000 to 100,000 miles. GM issued multiple Technical Service Bulletins acknowledging the issue. Many owners describe a persistent vibration felt through the entire vehicle especially between 40 and 70 mph.
Estimated Repair Cost
$2,500 to $4,500
900+
owner complaints
Recall Alert
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AFM Lifter Technical Service Bulletins Issued by GM
Check NHTSA for open recalls on your specific VIN
GM has issued multiple Technical Service Bulletins related to AFM lifter failures on 2014 through 2021 Silverados and Sierras. The 2018 Silverado shares the same platform and engines as the 2018 GMC Sierra meaning both trucks carry identical risks. Always check for open recalls on the specific VIN using the NHTSA recall database before purchasing.
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