Studebaker President Brake Light Switch Guide: 1948-1952
Having trouble with your brake lights? The original hydraulic switch is a common point of failure, but reliable solutions are available.
- No major aftermarket brands offer a direct-fit part, but reproduction hydraulic switches are available from Studebaker specialists.
- Before buying a hydraulic switch, check if your car uses screw-on or push-on wire terminals.
- Original-style hydraulic switches are unreliable and often fail when used with modern DOT 5 silicone brake fluid.
- Upgrading to a universal mechanical switch is a popular, inexpensive, and more reliable long-term solution.
Understanding the Original 1948-1952 Brake Light Switch
The original brake light switch on these Studebakers is a hydraulic design. This means it relies on pressure from the brake fluid to work. While simple, these switches are a known weak point, especially after 70+ years. They are prone to failure and can be unreliable. A common issue is the switch requiring very high pedal pressure to activate the lights, which is a significant safety hazard. They can also fail in the 'on' position, leaving your brake lights stuck on and draining the battery.
Silicone Brake Fluid Warning
Many classic car owners switch to DOT 5 silicone brake fluid. However, original-style hydraulic brake light switches are known to fail quickly when used with silicone fluid. If you use or plan to use silicone fluid, a mechanical switch upgrade is the most reliable option.
Choosing the Right Replacement Part
While you won't find brands like Duralast or ACDelco listing a direct-fit part for this vehicle, solutions are readily available from Studebaker specialists and universal parts suppliers. You have two main options: a reproduction hydraulic switch or upgrading to a modern mechanical switch.
Option 1: Direct Replacement (Reproduction Hydraulic Switch)
This is the easiest and most original-looking repair. Several Studebaker parts specialists sell new reproduction hydraulic switches. Before ordering, you must check which type of electrical connection your car has.
- Push-Type Terminals: Part number 666858 is a common reproduction for 1942-66 Studebakers and features push-on spade terminals.
- Screw-Type Terminals: Part number 191078 was used on models up to 1950 and uses screw-on terminals for the wires.
Pro Tip: Always check your existing switch's terminals before ordering a replacement to ensure you get the correct part.
Option 2: Mechanical Switch Upgrade (Most Reliable)
For a permanent, more reliable solution, many owners convert to a universal mechanical brake light switch. This type of switch is activated by the physical movement of the brake pedal arm, not by fluid pressure. This makes it more responsive and reliable.
Benefits of a Mechanical Switch:
- Not affected by the type of brake fluid used (DOT 3, 4, or 5).
- Activates instantly with the slightest pedal movement.
- Removes a potential brake fluid leak point from the system.
- Inexpensive and widely available from parts stores like NAPA (Echlin SL128 is a part number some owners have used).
Installation requires fabricating a small bracket to mount the switch so the brake pedal arm makes contact with its plunger or lever. The wiring is then re-routed from the old hydraulic switch location to the new switch under the dash. While more involved than a direct swap, it is a common and highly recommended upgrade for safety and reliability.
| Part Type | Estimated Cost | Notes |
|---|---|---|
| New Reproduction (Hydraulic) | $15 - $35 | Available from Studebaker specialists. Check terminal type. |
| New Universal (Mechanical) | $10 - $25 | Requires custom installation. A popular, reliable upgrade. |
| New Old Stock (NOS) OEM | $40+ (Variable) | Very rare. May have aged seals. Not recommended over new reproductions. |
| Used OEM | $10 - $30 (Variable) | Not recommended due to age and high failure rate. |
| Shop Labor | $50 - $150 | Higher end of range reflects labor for a mechanical switch conversion. |
Frequently Asked Questions (FAQ)
Why did my brake lights stop working?
The most common cause is a failed hydraulic brake light switch. It can get stuck internally, preventing it from completing the circuit. Before replacing the switch, always check the fuse and the bulbs first.
Why are my brake lights stuck on?
This is also a symptom of a failed brake light switch. The switch can fail in the 'closed' or 'on' position, continuously sending power to the lights and draining your battery.
Where is the brake light switch located?
It is not on the brake pedal. Look for a small, brass-colored switch with two wires attached, screwed into the master cylinder or a nearby brake line junction block under the car.
Is it hard to replace the brake light switch?
Replacing the original hydraulic switch with another is easy. You disconnect the wires, unscrew the old switch, and screw in the new one. You may need to bleed the brakes afterward to remove any air that entered the system. Converting to a mechanical switch is more difficult as it requires making a bracket and running new wires.
Are there any recalls for the brake light switch?
There are no specific NHTSA recalls found for the brake light switch on the 1948-1952 Studebaker President. Recalls for this part on modern cars often relate to poor internal connections causing the lights to fail or stay on.
Technical Specifications
OEM Part Numbers: 666858 191078
Hydraulic pressure activated switch with a 1/8-inch NPT thread. Available with either screw-type or push-type (spade) electrical terminals.
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.