There’s nothing quite like the dread of hearing a strange noise from your car or spotting a warning light on the dashboard. It’s a sinking feeling we all know too well. But did you know that many of these issues can be traced back to a handful of bad driving habits? That’s right—everyday mistakes that most of us are guilty of could be leading to catastrophic engine failure down the road.
Replacing an engine isn’t just costly—it’s one of the most stressful repairs you’ll face. That’s why we’re here to highlight five specific driving habits that are absolute engine killers. These aren’t vague tips; they’re backed by over 20 years of experience under the hood. Let’s dive in.
1. Constant Low RPM Driving
It’s easy to assume that keeping your RPMs low is good for fuel economy—and to an extent, that’s true. But if you’re constantly driving at very low RPMs (under 1,500), especially in modern engines, you could be doing serious damage.
This habit leads to a condition called glazing, where the cylinder walls become polished to a mirror-like finish. While that might sound ideal, it actually causes oil burn-off and carbon buildup. The carbon acts like a sponge, soaking up oil instead of letting it lubricate the engine properly. The result? Increased friction, hot spots, and premature engine wear.
The Fix: Let your engine stretch its legs. Vary your RPMs and allow your engine to operate at higher revs occasionally. This keeps oil circulating and combustion chambers clean.
2. Excessive Engine Braking
Using your engine to slow down—known as engine braking—can reduce brake wear, making it seem like a smart move. But overdoing it puts immense stress on components like transmission bearings, synchros, and mounts, which aren’t built for that kind of strain.
Over time, this added pressure leads to wear and tear on precision parts, causing slipping, clunking, and grinding in the transmission. Repairs for these issues can cost anywhere from $2,000 to $4,000—or more.
The Fix: Use engine braking sparingly. It’s helpful on steep hills, but rely on your actual brakes for regular deceleration.
3. Running on Low Fuel
We’ve all pushed the limits of our fuel gauge, but driving on an almost-empty tank can wreak havoc on your fuel system. Your fuel pump relies on gasoline for cooling and lubrication. When you run low, the pump starts sucking up sediment and debris from the bottom of the tank, which clogs filters and damages injectors.
This abuse can lead to a prematurely failed fuel pump and rough engine performance, costing hundreds or even thousands of dollars to fix.
The Fix: Keep your fuel tank reasonably topped up. It’s an easy way to extend the life of your fuel system and avoid costly repairs.
4. Rushing from Reverse to Drive
Switching from reverse to drive without coming to a full stop might seem like a time-saver, but it’s a surefire way to damage your transmission. Your car’s transmission is a finely tuned machine, not designed to handle abrupt shifts while the vehicle is still moving.
Repeatedly doing this can cause slipped gears, stripped clutch packs, and even sheared bolts. These repairs can easily cost over $3,000.
The Fix: Take an extra second to fully stop before shifting from reverse to drive. This simple step can add years to your transmission’s life.
5. Accelerating in High Gear
Modern transmissions with eight, nine, or even ten gears can make it tempting to accelerate in high gear. But stomping the gas pedal while in a high gear places immense stress on your engine’s components, like connecting rods and bearings.
Frequent high-gear acceleration can lead to catastrophic issues such as spun rods, destroyed crank bearings, and detonation damage. These problems often require a complete engine rebuild, costing thousands.
The Fix: Allow your engine’s RPMs to climb during hard acceleration before shifting gears. This reduces strain on internal components and prevents long-term damage.
Drive Smarter, Not Harder
Bad driving habits can be costly—but they’re also easy to fix once you know what to avoid. By addressing these five habits, you’ll not only save thousands in repair bills but also keep your car running smoothly for years to come.
