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1958 Studebaker 3E5 Brake Light Switch Guide

Keep your classic Studebaker truck safe and its brake lights working with the right replacement switch.

3 minutes to read 1958-1958 Studebaker 3E5
Difficulty
2/5
Est. Time
0.75 hrs
DIY Doable?
✅ Yes
Shop Labor
$50-$100
Used OEM Price
$10-$25
🚫 Do not drive — Driving without functional brake lights is illegal and extremely dangerous to you and other motorists.
Key Takeaways
  • A faulty brake light switch is a critical safety failure; do not drive if your brake lights are not working.
  • For a 1958 Studebaker 3E5, a new aftermarket switch from a brand like Standard Ignition is the most reliable and practical option.
  • The most common symptoms are brake lights that don't turn on or stay on constantly.
  • Replacement is a simple DIY job, but if it is a hydraulic switch, you must bleed the brakes afterward for safety.
The brake light switch on your 1958 Studebaker 3E5 is a critical safety part. On many classic trucks from this era, the switch is activated by hydraulic pressure from the brake fluid itself. When you press the brake pedal, the building pressure activates the switch, which completes an electrical circuit to turn on the brake lights. This tells drivers behind you that you are slowing down or stopping. Because of its design, it is a common wear item that fails over time.

Is Your Studebaker's Brake Light Switch Failing?

On a classic truck like the 1958 Studebaker 3E5, you won't get a warning light on your dashboard for a failing brake light switch. A visual check is the only way to know if it's working. The symptoms are usually straightforward and present a major safety risk if ignored.

Critical Safety Warning

Do not drive your vehicle if the brake lights are not working. It is illegal and extremely dangerous for you and other drivers on the road. A faulty brake light switch requires immediate attention.

Choosing the Right Aftermarket Switch

For a vehicle built in 1958, finding new original equipment (OEM) parts from Studebaker is not a realistic option. Your choices are typically limited to New Old Stock (NOS), used original parts, or new aftermarket parts.

  • New Old Stock (NOS): These are original parts that were never installed. They can be very expensive and difficult to find. Rubber and plastic components may have degraded over decades of storage.
  • Used OEM: Pulled from a salvaged vehicle, these parts are inexpensive but their remaining lifespan is unknown.
  • New Aftermarket: This is the most practical and reliable choice. A new switch from a reputable brand like Standard Ignition is made with modern materials and often exceeds the quality of the original 1950s part. Standard Ignition is a well-regarded manufacturer of automotive electrical components.

Pro Tip: Before you replace the switch, always check the simple things first. Make sure the brake light bulbs haven't burned out and that the fuse for the circuit is good. Also, inspect the wiring to the switch for any obvious damage.

Potential Replacement Costs for Your Studebaker 3E5

The cost to replace the brake light switch is very reasonable, especially if you do the work yourself. The only brand readily available in the new aftermarket is Standard Ignition.

Part Type Estimated Cost
New Aftermarket (Standard Ignition) $15.52
New Old Stock (NOS) $30 - $75+ (If found)
Used OEM $10 - $25
Shop Labor $50 - $100

Frequently Asked Questions (FAQ)

Where is the brake light switch located?

On many Studebakers of this era, the brake light switch is a hydraulic pressure switch. It is not located by the brake pedal inside the cab. Instead, it is screwed directly 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.

How do I test my brake light switch?

After confirming the bulbs and fuse are good, locate the switch. Unplug the two wires and use a small jumper wire to connect them together. If the brake lights turn on, the switch is bad and needs to be replaced. If they do not light up, you have a problem elsewhere in the wiring.

Can a bad brake light switch drain my battery?

Yes. If the switch fails in the "on" or closed position, it will keep the brake lights illuminated even when the truck is off. This will drain your battery.

Is this a difficult part to replace myself?

For a DIY mechanic, this is a relatively easy job. It involves unplugging the wires and unscrewing the switch. However, if it is a hydraulic switch, you must be prepared to quickly install the new one to minimize brake fluid loss. It is highly recommended to bleed the brakes after replacement to ensure no air has entered the system, which is critical for safety.

Are there any recalls for the 1958 Studebaker 3E5 brake light switch?

No active recalls or Technical Service Bulletins (TSBs) from the National Highway Traffic Safety Administration (NHTSA) were found for the brake light switch on this specific vehicle, which is normal for a truck of this age.

Technical Specifications

OEM Part Numbers: 666858

Hydraulic pressure-activated switch, typically with a 1/8-inch NPT thread and a 2-terminal electrical connection.

Wrenchy
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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.

Year Coverage
This article covers the Brake Light Switch for:
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