Brake Light Switch Guide for the 1938 Studebaker State Commander
Understanding the crucial hydraulic brake light switch in your classic 1938 Studebaker State Commander.
- The 1938 State Commander uses a hydraulic pressure switch, not a mechanical one by the pedal.
- Replacement requires bleeding the brakes to remove air from the lines.
- Standard Ignition is the primary aftermarket brand available for this classic vehicle.
- Driving with a faulty brake light switch is illegal and extremely dangerous; do not operate the vehicle until it is fixed.
Is Your Studebaker's Brake Light Switch Failing?
The brake light switch is a critical safety component on your 1938 State Commander. Unlike modern cars that use a switch at the pedal, your Studebaker uses a hydraulic switch that activates with brake fluid pressure. Over many decades, the internal parts of this switch, like the diaphragm and electrical contacts, can wear out or fail. This can lead to dangerous situations where your brake lights don't work at all or stay on constantly.
A Note on Aftermarket Switch Quality
Owners of various classic cars report that the quality of modern reproduction hydraulic brake light switches can be inconsistent. Some may fail prematurely or require much harder brake pedal pressure to activate than expected. While a new switch is the correct replacement, it's a known issue in the classic car community that their service life can sometimes be short. Some restorers even convert to more reliable, modern mechanical switches, but this requires custom fabrication.
Choosing the Right Aftermarket Switch
Finding a "New Old Stock" (NOS) original Studebaker switch is nearly impossible. For most owners, a new aftermarket replacement is the only practical choice. The most common brand available that fits the 1938 State Commander is Standard Ignition (also sold as Standard Motor Products or SMP). Standard is a well-known manufacturer that produces reliable parts for many classic vehicles. Given the scarcity of original parts, a new switch from a reputable brand like Standard is the recommended solution.
Brake Light Switch Cost for 1938 Studebaker State Commander
| Part Type | Estimated Cost |
|---|---|
| New OEM (NOS) | $75 - $200+ (if found) |
| New Aftermarket | $38.97 |
| Shop Labor | $50 - $100 |
Installation Tip
The brake light switch is typically screwed into the master cylinder or a brake line junction block. Because it is part of the hydraulic system, you must bleed the brakes after replacing the switch to remove any air that entered the lines. Failure to do so will result in a soft or non-functional brake pedal. Applying thread sealant to the new switch's threads is also recommended to prevent leaks.
Frequently Asked Questions (FAQ)
Where is the brake light switch located on my 1938 State Commander?
The switch is not inside the car. Look for a small, button-like sensor with two wire terminals screwed directly into the brake master cylinder, which is located in the engine bay on the firewall.
Do I have to bleed the brakes after replacing this switch?
Yes. Because the switch is threaded into the hydraulic brake lines, removing it introduces air into the system. You must bleed the brakes to ensure they function safely and effectively after the replacement is complete.
Why choose a new aftermarket switch over a New Old Stock (NOS) part?
While NOS parts are original, they are also over 80 years old. Rubber and plastic components can become brittle and fail quickly. A new aftermarket switch from a brand like Standard Ignition is made with modern materials and is generally more reliable and readily available than a rare and expensive NOS part.
My new switch only works when I press the brake pedal very hard. Is it faulty?
This is a common complaint with some reproduction hydraulic switches. They can require higher pressure to activate than original switches did. If your lights only come on during hard stops, the switch is the likely cause and you may want to try a replacement from a different source or a low-pressure switch designed for motorcycles, which some classic car owners use.
Technical Specifications
OEM Part Numbers: 193032 666858 191078
Type: Hydraulic Pressure Activated, Thread: 1/8-27 NPT
We Have This Part in Stock
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.