5 Car Accessories That Make Your Car Consume More Fuel

Kenyans love to personalize their cars. Whether it’s adding a bull bar for a tougher look, installing a powerful sound system, or getting bigger tyres “for stability,” many of these upgrades feel like small lifestyle improvements.

But what most drivers don’t realise is that some popular accessories come with a hidden cost: higher fuel consumption.

With fuel prices fluctuating and many households already stretched by daily commuting and school drop-offs, anything that makes your car burn extra fuel hits your budget hard. Below are the top five accessories that could be quietly increasing your fuel consumption.

Read more: 5 Car Accessories That Will Cause More Damage to Your Vehicle

1. Bull Bars

Bull bars, especially loved by Kenyans who own SUVs and double-cabins and make the car look rugged and give a sense of safety in case of minor collisions. 

But there’s the hidden downside as bull bars add significant weight and disrupt your car’s aerodynamics.

How they increase fuel consumption:

• A bull bar can add 20–40 kg of extra weight. More weight means the engine works harder, especially when accelerating.
• Bull bars change how air flows around the front of the car, increasing drag.

Combined, these two factors can increase your fuel consumption by 3 – 10%, depending on your car model. If you don’t genuinely need the bull bar (e.g., you mainly drive in Nairobi or other urban roads), consider removing it.

2. Roof Racks

Roof racks are useful for long-distance travel as thousands of Kenyan families load their cars with suitcases, bags that couldn’t fit in the boot. For that, roof racks are a lifesaver.

Roof racks drastically increase aerodynamic drag—even when they’re empty. Therefore, your car has to use more power to cut through the air, especially at higher speeds.

Studies show that roof racks can increase fuel consumption by 5% on city roads and up to 15% on the highway

It is advisable to remove the roof rack when you’re not using it and only reinstall it for road trips or heavy luggage days.

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3. Heavy Car Tyres and Rims

Bigger tyres and heavy rims make your car look stylish and often give better road grip. But the trade-off is significant.

Heavier tyres require more energy to rotate. They increase rolling resistance, meaning the engine must work harder. Oversized tyres also interfere with the car’s calibrated fuel efficiency system. They make acceleration slower and more costly.

A switch to heavier tyres can increase fuel usage by 3–8%, depending on the size difference.

Instead of installing heavy tyres, stick to the tyre size recommended by your manufacturer. If you want upgrades, choose lightweight alloy rims. Also, keep your tyres properly inflated—underinflated tyres also waste fuel.

4. Spoilers

Spoilers look sporty. Many Kenyan drivers install them, hoping to make their car look like it’s ready for a racing event. But on most standard cars, spoilers do the opposite of what you think.

Spoilers do not improve stability or efficiency as they increase total vehicle weight, air drag, depending on design and engine workload.

Poorly installed or purely decorative spoilers can raise fuel consumption by 2–5% and sometimes more if the spoiler disrupts airflow significantly. If you don’t need the spoiler for performance reasons (track driving, racing), consider removing it. You save fuel and reduce unnecessary strain on the car.

Read more: My Experience Driving the Classic 1988 Mercedes W124 That I Bought for Ksh700K 

5. Heavy Sound Systems

A good sound system adds weight. A full aftermarket sound system upgrade can add 10–60 kg to your car. This extra weight means your engine has to burn more fuel to keep the car moving efficiently.

Additionally, bigger amplifiers take more power from the alternator, and the alternator draws more power from the engine. This results in more fuel being burned.

Instead, choose lightweight speaker designs, avoid oversized subwoofer boxes. If you're fuel-conscious, stick to factory speakers or modest upgrades.