9 Common Hidden Problems From a Rear-End Collision

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Rear-end collisions make up 29% of car accidents in the U.S. The reason for this high prevalence is that such accidents can occur without the knowledge of the driver. As a mechanic, it is your responsibility to ensure your client’s car is restored to its condition before the accident and that every bit of damage is addressed.

Sadly, not all cracks and dents are obvious after a collision. Without a proper and comprehensive diagnostic procedure, you may miss out on some hidden damages and hand your client a half-repaired car. Read on for some common problems that go unnoticed following a rear-end collision:

Transmission issues

Transmission issues are relatively difficult to detect since most of them happen gradually. Experienced repair experts such as Crash Champions always test for this after fixing the physical outer damage. Telltale signs of transmission damage include transmission fluid leakage, a slipping transmission, and difficulty shifting gears. Extra scrutiny is required if the vehicle is a rear-wheel or all-wheel drive.

Damage to electronic components

Newer vehicle models are equipped with plenty of electronic components, some of which are located on the vehicle’s rear side. Some of those components include electrical grounds, distance sensors, engine control CPUs, body modules for power windows and air conditioners, and sound system amplifiers. No matter the collision’s seriousness, always run tests on all electrical systems before deeming the repair project complete. Additionally, ask the client about any electrical modifications on the car for a clearer picture of what you are up against.

Car alignment problems

If hitting a pothole can knock a well-maintained vehicle out of alignment, imagine what impact from the rear can do. You can tell if a vehicle’s alignment has been compromised if it tends to pull to one side when you drive it. Strange vibrations and a steering wheel shimmy when traveling at certain speeds might also indicate your vehicle is misaligned.

Note that car alignment damage mostly gets worse over time, so there is a chance what seems negligible at the moment will balloon into a full-blown problem in the future. With that being said, you may be held liable for any accident involving the vehicle that is connected to alignment problems that you didn’t fix.

Damaged frame

Most of today’s vehicles are fitted with plastic bumpers. These are easily dented or cracked, and damage to them may well translate to damage on the frame. Before changing your client’s bumper, make sure to check if the damage went all the way in. The car’s frame may be bent or even cracked, and if it is not repaired immediately, the vehicle will be less safe to its users in future collisions. It will probably also affect the car’s aesthetic appeal and lower its resale value.

Trunk damage

The trunk is one of the biggest casualties of rear-end collisions. While damage to it is expected and easy to spot, a lack of detailed assessment and repair can leave the trunk’s seal and locking system damaged. This will lead to several long-term effects:

  • The car’s resale value will fall
  • Contents in the trunk might be left exposed to theft
  • The vehicle will be more vulnerable to snow and rain damage, which will accelerate the car’s deterioration and invite negative feedback from the owner

Engine problems

Today’s cars are equipped with highly delicate and complex engines that could pick up damage from far-fetched impacts, such as a rear-end collision. When a client brings a rear-ended car for repair, don’t just focus on the backside. Check under the hood and ensure everything is in place. Also, ensure the “check engine” warning isn’t on.

Sometimes, the impact from the rear side can cause damage to the car’s drivetrain. This may occur if the exhaust system is pushed forward, causing damage to the vehicle’s catalytic converter, muffler, exhaust manifold, and engine mounts.

Suspension issues

The role of the suspension system in ensuring the stability of the car is critical. A car’s suspension basically maximizes the tire’s grip on the road, facilitating smooth steering and handling of the vehicle. Unfortunately, the frame damage that is characteristic of rear-end collisions can increase pressure on the suspension and accelerate wear on the struts, shocks, and other components of the suspension system. The alignment problem mentioned earlier is also a common culprit behind damage to the suspension components.

Taillight issues

If the taillights are broken, it should be the first thing you see as the car is towed to your garage. Unfortunately, the damage isn’t always apparent. The light covers might be slightly jolted out of position, potentially compromising the visibility of the bulb beneath. What’s more, it would be difficult to perceive a tiny crack without proper, in-depth scrutiny of the cover. These cracks let in dust and moisture and gradually lower the light’s brightness or cause it to conk out abruptly mid-journey. Even if there is no direct damage on the tail light, check to ensure impact elsewhere didn’t cause small cracks or alignment problems.

Damage to the rear windshield

Damage to the rear windshield is almost always bound to happen following a rear-end collision. Minor collisions might spare the glass, but that shouldn’t stop you from examining it.

It is not uncommon for the front and rear windshields to sustain invisible cracks and chips along the edges due to the impact on the frames holding them. If there is a bend anywhere near the windshields, there is a good chance some of the impacts went to the glass. Take the time to examine it in case there are minor cracks that need to be sealed.

Some of the damage on the windshield might result from the repair works rather than the collision itself, so take extra caution when fixing damage near the glass to avoid aggravating it.


Rear-end collisions might not be as deadly as head-on collisions, but their impact on the car cannot be deemed insignificant. Make sure to include the above-hidden damages in your inspection checklist for a more fruitful repair project.

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