I am going to go through a series of examples of why it is beneficial to use an OEM (Original Equipment Manufacturer) auto part rather then an aftermarket one.
Here is and exapmle of GM parts.
Reaon 1. The design of the OEM part is far more advanced.The GM energy absorber has thicker cell walls in the main crush zone than the non-OEM part. Crush zones help absorb the impact of the crash thereby reducing damage to the vehicle.
The non-OEM rear beam is missing the reinforcement channel, which is designed as a stiffener and helps keep the part from unnecessary flexing in a crash.
Reason 2. The OEM auto part is made of quality material.The GM beam is formed from a single piece of metal while the non-OEM beam is made from two overlapping, spot-welded pieces. This design allows the GM beam to better distribute energy in a crash.
The walls of the energy absorber are up to 2.3 mm thicker on certain areas of the GM part. Wall thickness helps dictate how the impact of the crash is distributed throughout the part and to the vehicle.
Reason 3. OEM auto parts have better weldsThe GM beam has six significantly larger welds while the non-OEM beam has ten smaller welds. GM engineers specifically locate welds in certain areas so they will
help to absorb and distribute the energy from an impact.
Reason 4. The fit of an aftermarket auto part is rarely right on.Before assembly, the rear fascias look similar, however, after installation there is a noticeable difference in the trunk lid and fascia fit. The poor fit requires additional labor to position the part and may affect your vehicle’s resale value.
Reason 5. The OEM auto parts are much more durable.Replicating the Insurance Institute for Highway Safety’s 5 mph rear-into-pole test caused a large dent on the decklid and trunk floor panel of the vehicle using non-OEM parts. The non-OEM parts were significantly deformed after the test, causing an incorrect fit.
Reason 6. Non-OEM auto parts create more damage in an accident.Engineers found that the differences in bumper components greatly affected part performance. The use of non-OEM parts resulted in more damage to the vehicle, increased costs $1,500, and extended repair time.
The Facts about these auto parts.Genuine GM Parts ❑ Proper fit and same materials as original parts
❑ Larger welds
❑ Efficient repairs
Genuine GM parts provide the opportunity to return your GM vehicle to pre-accident condition.
Non-OEM Parts ❑ Missing features
❑ Greater potential impact damage
❑ Different design and materials
❑ Damage exceeds vehicle equipped with genuine GM parts by approximately $1,500.
Clearly not “functionally equivalent” to genuine GM parts.
This information is from a GM Goodwrench
Impacting Collision Repair Consumer Brochure.GM Goodwrench Web Site