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1959 Studebaker 4E7 Truck Brake Light Switch Guide

Get your classic Studebaker truck's brake lights working safely and reliably.

3 minutes to read 1959-1959 Studebaker 4E7
Difficulty
2/5
Est. Time
0.75 hrs
DIY Doable?
✅ Yes
Shop Labor
$50-$100
Used OEM Price
$5-$15
🚫 Do not drive — It is illegal and extremely dangerous to drive a vehicle without functioning brake lights.
Key Takeaways
  • A faulty brake light switch is a critical safety failure; do not drive if your brake lights are not working.
  • The 1959 Studebaker 4E7 likely uses a hydraulic pressure switch located on the master cylinder or brake lines, not at the pedal.
  • A new aftermarket switch from a brand like Standard Ignition is the most reliable and cost-effective replacement.
  • Replacement is a simple DIY task, but you must bleed the brakes afterward to ensure safety.
On your 1959 Studebaker 4E7 truck, the brake light switch is a critical safety part. Unlike many modern vehicles, these classic trucks often use a hydraulic pressure switch. This switch is screwed directly into the brake lines or master cylinder. When you press the brake pedal, the pressure of the brake fluid activates the switch. This completes an electrical circuit, sending power to the brake lights and telling drivers behind you that you are slowing down.

Symptoms of a Failing Brake Light Switch

A bad brake light switch on a vintage truck like the 4E7 has very clear symptoms. Because this part is essential for safety, you should address these issues immediately.

  • Brake Lights Do Not Work: This is the most common and dangerous symptom. The switch has failed and no longer completes the circuit when you press the brake pedal.
  • Brake Lights Stay On: The switch can get stuck in the 'on' position, leaving the brake lights illuminated even when the truck is parked. This will drain your battery and confuse other drivers.
  • Lights Only Work With Hard Braking: An aging hydraulic switch might require more fluid pressure than normal to activate. This means your lights might not turn on during gentle stops, creating a serious hazard.

Safety First

Before assuming the switch is bad, always check your brake light bulbs and the fuse first. These are simple and common failure points that are easy to fix.

Choosing the Right Aftermarket Switch

For a 1959 vehicle, finding new original equipment (OEM) parts is not a realistic option. Your choice is between a used original part, New Old Stock (NOS), or a new aftermarket part.

  • New Aftermarket (Recommended): A new switch from a reputable brand like Standard Ignition is the best choice. Modern manufacturing provides a reliable and affordable part that meets or exceeds original specifications. These switches are designed as direct replacements.
  • New Old Stock (NOS): These are original, unused parts. While authentic, they can be very expensive, and materials like rubber or plastic may have degraded over decades on a shelf.
  • Used OEM: A used switch from a salvage yard is the cheapest option but not recommended. For a low-cost, critical safety part, the risk of it failing shortly after installation is not worth the small savings.

Pro Tip: Some Studebaker owners convert their old hydraulic pressure switches to a more modern mechanical switch mounted at the brake pedal. This eliminates issues with fluid compatibility (like with silicone brake fluid) and potential leaks. However, for a direct and simple replacement, a new hydraulic switch is the easiest path.

Estimated Replacement Costs

Replacing the brake light switch on your Studebaker 4E7 is an inexpensive repair. The part itself is affordable, and labor is minimal.

Item Estimated Cost
New Aftermarket Switch $15 - $20
Shop Labor $50 - $100
Total Estimated Cost $65 - $120

Note: Costs are estimates and can vary based on your location and local labor rates. The job is simple enough for most DIY mechanics.

Frequently Asked Questions (FAQ)

Where is the brake light switch located on a 1959 Studebaker 4E7?

On most Studebakers of this era, the brake light switch is a hydraulic pressure switch. It is not located by the brake pedal inside the cab. You will typically find it screwed into the master cylinder or a brake line junction block in the engine bay or on the frame. It will have two wires connected to it.

Is replacing the brake light switch a difficult DIY job?

No, for someone with basic mechanical skills, it is a straightforward job. It involves disconnecting the wires, unscrewing the old switch, and quickly installing the new one to minimize brake fluid loss. However, it is critical to bleed the brakes after replacement to remove any air that may have entered the system.

How do I test the brake light switch?

A simple way to test if the switch is the problem is to locate the switch and unplug the two wires. Carefully use a small jumper wire to connect the two terminals on the wiring harness side. If the brake lights turn on, the switch is faulty. If they do not, the problem lies elsewhere in the wiring, fuse, or bulbs.

Are there any recalls for the brake light switch on my Studebaker truck?

There are no recorded safety recalls on file with the National Highway Traffic Safety Administration (NHTSA) for the 1959 Studebaker 4E7 concerning the brake light switch or related components.

Technical Specifications

OEM Part Numbers: 666858

Hydraulic Pressure Activated Switch, 2-Terminal, 1/8-27 NPT thread size.

Wrenchy
Article researched & written by
Go-Parts' AI research assistant. Every article is backed by live web research, verified OEM data, and real technician knowledge — so you get accurate, up-to-date information you can trust.
Meet Wrenchy → Updated Jul 21, 2026

The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.

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