Red Flags to Look For During a Routine Inspection

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As you know, many car owners have absolutely no idea how to inspect their vehicle on a regular basis. They just don’t know what to look for. So when you’ve got a vehicle in for a minor repair or routine maintenance, check the items listed below. You might catch a problem before is becomes a major headache for your customer. If you can do that, you’ll have a happy customer, and you’ll generate some revenue for your shop.


1. Check the Coolant for Contamination and Leakage

Pull off the radiator cap, and look for an oil sheen on top of the coolant. This would indicate a leaking head gasket. If it’s been leaking for a while, you might see a brown sludge. If you see a pinkish tint or foam, the transmission fluid might be leaking into the coolant.

2. Check the Oil Fill Cap

Look at the underside of the cap for a brown sludge, which would indicate a bad head gasket.

3. Check The Dipstick

Check the dipstick for oil level. Many car owners never check the oil level. If the oil level is too high, a bad head gasket might be letting coolant leak into the oil. Any sludge on the dipstick might also mean a bad head gasket.

4. Check the Transmission Fluid

Transmission fluid should be pinkish, even on higher mileage cars. If there is any foam, or the level is too high, suspect coolant contamination.

5. Torn CV Boots

Obviously, a torn CV boot will eventually cause the CV joint to fail.

6. Wheel Bearings

If you’ve got the car on a lift, check each wheel for wheel bearing issues.

7. Worn Brake Pads

When the brake pads are down to 1/8 to 3/16 of an inch, they need to be replaced. Some customers put off replacing pads because they don’t realize that they can completely destroy their rotors if they wait too long.

8. Worn Tires

Of course, most customers know about how worn their tires are. But you should still look for uneven wear, which might indicate an alignment problem. Cupping may indicate worn ball joints.

9. Water Pump Weep Hole

Any coolant leakage from the weep hole means that the water pump doesn’t have long to live.

10. Serpentine Belt

Check for slack tension and unusual wear.

11. Burnt Out Brake Lights or Turn Signal Lights

It’s easy for a car owner to overlook burnt out brake lights or turn signal lights on the back of their car. And, since it is critical to their safety, most car owners will appreciate that you checked.

12. Dirty Air Filter

If the air filter on a customer’s car is so dirty that you can’t see any light shine through it, they are probably way behind on other routine maintenance items.


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