Here, part by part, are specific examples of the quality issues in materials, design and manufacturing as well as the probable problems that would result.

-Selected from Cummins website

Part	Issue	Damage/Performance Impact
Pistons	Shallow ring grooves out-of-spec bowl demensions	Ring breakage, high oil consumption, blowby, scuffing
Piston rings	Out-of-spec ring angles	Insufficient sealing, excess fuel usage, decreased performance
Piston pins	Out-of-spec outer diameters	Incorrect fit issues, repair delays
Cylinder Liners	oversize outer/inner diameters, Insufficient metal strength	Metal fatigue, coolant leaks, pitting, mission-disabling failure
Valve Springs	Below spec for Hardness, Insufficient Height Load	Degraded performance over time, Combustion Leaks & premature wear-out of valve seat inserts
Valve seat inserts	Runout does not meet specifications, can’t square to seat	Increased Wear, Combustion Leakage, potential valve failure
Connecting rod bearings	Tangs too narrow, Metals not cast, Excess lead pooling	Interference issues, Lower corrosion resistance, Fatigue cracking
Connecting rod bushings	Excess Lead in Lining Layer	Delamination and cracking