Ford Bronco II Third Brake Light Upgrade & Installation Guide
This guide documents how to add a third brake light (center high mount stop lamp) to a Ford Bronco II using a factory-style light from a 1995–2005 Chevy Astro Van or Chevy S-10 Blazer. The installation covers wiring the third brake light into the factory brake light circuit, routing wiring through the A-pillar and headliner, mounting the light to the rear hatch, and sealing it properly to prevent leaks.
This modification improves rear visibility and braking safety while maintaining a clean, OEM-style appearance. The article includes step-by-step photos, wiring details, mounting tips, before-and-after images, and updated modern replacement options using LED third brake lights that are readily available today.
Topics covered: Ford Bronco II third brake light installation, brake light wiring, center high mount stop lamp (CHMSL), Chevy Astro third brake light swap, S-10 Blazer brake light, rear hatch mounting, LED brake light upgrade.
Introduction
When the third brake lights started showing up in the 1980’s, I thought they were pretty dumb looking. But since they have been around a while I find they do make it easier to tell if the car in front is stopping.
I wanted to update the Bronco II, so I started looking for a 3rd brake light assembly to install on it. I liked the shape of the light on my Astro Van, so I went to the wrecking yard and got this 3rd brake light from a 1995-2005 Chevy Astro Van:
The Chevy S-10 Blazer used a similar style 3rd brake light.
First step was to pull the trim off above the door, back window and hatch. I also took the trim off the A-Pillar.

I ran a wire from the green wire on the brake light switch up the A-pillar and back to the rear dome light. There is a wire bundle that runs the whole length that goes to the electric hatch lock and dome light. I used wire ties to secure the wire to that bundle.

This was the hardest part since the headliner backing is very brittle and would break if bent very much.
Next, I marked and drilled the holes for the tabs on the bottom of the light, and for the wires to run through.

I stayed close to the hatch so that the screws and wires would end up in the metal brace that runs across the hatch. I ran a ground to the dome light ground and put it all back together. The light had a foam gasket on it, but I still ran a bead of clear RTV around the holes and mount screws to make sure it didn’t leak.
Before

After


Update
This is an old submission, but the idea is still a good one, but you don’t necessarily have to go hunting in a salvage yard to find a 20-year old light assembly from a Chevy Astro Van or S-10 Blazer. I found these replacement lights doing a search on Amazon.
ZULOW 3rd Third Brake Light (Smoked)
ZULOW 3rd Third Brake Light Smoked Led High Mount 3rd Brake Stop Light Cargo Lamp For Astro 1995-2005:
DOTCOM LED 3rd Brake Light (Clear)
DOTCOM LED 3rd Brake Light, Compatible with 1992-2004 Chevy, clear lens with black housing.
Tresound 3rd Third Brake Light (Smoked)
Tresound 3rd Third Brake Light for 1994-2005 Blazer, 1996-2001 Bravada, LED High Mount Lamp Stop Light (Smoked)
Last Updated:
About The Author
Jim Oaks is a longtime Ford truck and SUV enthusiast and the founder of The Ranger Station and Bronco II Corral. With decades of hands-on experience, he writes both technical and non-technical articles covering the Ford Bronco II, including mechanical systems, factory engineering, common upgrades, and detailed feature vehicle write-ups.
In addition to technical content, Jim documents Bronco II history, rare factory and aftermarket models, production details, and original Ford marketing materials. His work is based on firsthand experience, original documentation, and long-term involvement in the Ford enthusiast community.
Through his sites, Jim has built comprehensive reference libraries that serve owners, builders, restorers, collectors, and historians, helping preserve the Bronco II’s technical knowledge and historical significance.










