What is the low beam headlight bulb size for a 1978 Mercedes-Benz 240D?

The 1978 Mercedes-Benz 240D uses a H6024 bulb for the low beam headlights. We recommend upgrading to LED for better visibility.

What is the high beam headlight bulb size for a 1978 Mercedes-Benz 240D?

The high beam bulb size for the 1978 Mercedes-Benz 240D is N/A.

Why are my 1978 Mercedes-Benz 240D headlights dim?

Dim headlights on a 1978 Mercedes-Benz 240D can be caused by aging halogen bulbs, which lose brightness over time, or oxidation (cloudiness) on the plastic headlight lenses. Upgrading to a H6024 LED conversion kit can provide a significantly brighter and whiter light output.

Which bulb fits the 1978 Mercedes-Benz 240D fog light?

The 1978 Mercedes-Benz 240D typically does not come with factory fog lights in all trim levels. If your vehicle is equipped with them, check the manual as sizes can vary by trim.

Is the 1978 Mercedes-Benz 240D single or dual beam?

The 1978 Mercedes-Benz 240D uses a dual bulb headlight system. This means you have separate bulbs for high and low beams.

Can I install LED bulbs on my 1978 Mercedes-Benz 240D?

Yes, the 1978 Mercedes-Benz 240D comes with standard halogen bulbs from the factory, but they can be upgraded to LED. You will need a H6024 LED conversion kit for the low beams.

Did the 1978 Mercedes-Benz 240D change headlight bulb sizes from the previous year?

No — the 1978 Mercedes-Benz 240D uses the same bulb sizes as the 1977 model. This configuration has been consistent across the 1977–1982 generation.

How do I change the headlight on a 1978 Mercedes-Benz 240D?

Turn off the vehicle and open the hood. Locate the headlight assembly from behind, remove the dust cover or retaining clip, disconnect the wiring harness, twist the old H6024 bulb counter-clockwise to remove it, then insert the new bulb and reassemble. Note: Mercedes-Benz vehicles use a CANbus system, so LED replacements may need an anti-flicker decoder. The whole process typically takes 10 to 30 minutes per side depending on accessibility.

Are LED headlights legal for a 1978 Mercedes-Benz 240D?

LED bulbs used off-road or in auxiliary lights are legal everywhere. For on-road headlight use, legality varies by state. Many states allow LED retrofits as long as the beam pattern meets DOT standards. For the best legal compliance, choose a DOT-approved H6024 LED kit that is designed as a direct replacement and produces a proper cutoff pattern without excessive glare.

How much does it cost to replace 1978 Mercedes-Benz 240D headlights?

A pair of halogen H6024 bulbs costs $15 to $40, while LED conversion kits run $25 to $60 per pair. If you have a shop do the work, expect an additional $20 to $50 in labor per bulb. Replacing them yourself at home saves the labor cost and usually takes under 30 minutes.

What is the difference between halogen and LED for a 1978 Mercedes-Benz 240D?

Halogen bulbs produce a warm yellow light (around 3200K), last 500 to 1000 hours, and draw more power. LED bulbs emit a brighter white light (5000-6000K), last 25,000+ hours, and use less energy. LED upgrades for the H6024 position are available as direct plug-and-play replacements. Since the Mercedes-Benz uses CANbus monitoring, choose a CANbus-compatible LED kit to avoid dashboard errors.

The 1978 Mercedes-Benz 240D shares its bulb sizes with the 1977–1982 generation.

Fitment Guaranteed for 1978 Mercedes-Benz 240D

What Size Bulbs Does a 1978 Mercedes-Benz 240D Use?

Correct headlight, fog light, and tail light bulb sizes. Sourced from OEM catalog data.

Installation Difficulty

Hard (Tight clearances)

Est. Replacement Cost

$15 - $40 (Halogen) / $30+ (LED)

What Lighting System Does the 1978 Mercedes-Benz 240D Have?

Owners of the 1978 Mercedes-Benz 240D will find a total of 4 lighting elements throughout the vehicle's exterior. It features a standard lighting system powered by a dual-bulb halogen configuration using separate H6024 low beam and high beam bulbs for precise light distribution. This model belongs to the mid years of the 240D's 1974-1982 production span. Note that Mercedes-Benz vehicles typically feature a CANbus electrical monitor that checks for specific bulb resistance.

LED Flicker Warning

This vehicle is known to use a CANbus system. Installing standard LEDs may cause flickering.

Use a CANbus decoder.

Can You Put LED Bulbs in a 1978 Mercedes-Benz 240D?

Upgrading to LED is one of the most effective ways to modernize your Mercedes-Benz's appearance and safety profile. We recommend starting your upgrade with the H6024 low beams, as they see the most use. Adding a matching LED kit later will complete the look and ensure consistent lighting performance. Because Mercedes-Benz utilizes a CANbus system, standard LED bulbs may cause "bulb out" errors on your dashboard. Always opt for "Error-Free" or CANbus-ready kits which include the necessary resistors.

1978 Mercedes-Benz 240D Bulb Size Chart

Position	Bulb Size	Shop
Low Beam	H6024	Buy H6024 →
Side Marker	7528	Buy 7528 →
Turn Signal Front	7528	Buy 7528 →
Parking Light	7528	Buy 7528 →

How do the 1978 Mercedes-Benz 240D's bulbs compare to other years?

The 1978 Mercedes-Benz 240D uses the same bulbs as the 1977 model.

The 1979 model continues with the same bulb sizes.

This bulb configuration covers the 1977–1982 model years. ← 1977 1979 →

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Other 240D Years

1982 1981 1980 1979 1977 1976 1975 1974

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