Brake / Tail Light LED Upgrade
Replace dim 1157 brake bulbs with LED 1157 from Philips, Diode Dynamics, or Sylvania Zevo. Brighter, faster turn-on (~50ms faster than incandescent = bigger safety margin).
Stock 1157 brake bulbs are double-filament incandescent — dim, slow to come up, and short-lived. LED 1157 replacements turn on roughly 50ms faster (a car length at 60 mph), draw less current, and last the life of the truck.
Key considerations:
- Get a 1157 with the proper offset pins (some clones get this wrong). Bay15d base.
- Resistor or load-equalizer may be needed for hyperflash (turn signal blinking fast because the BCM detects 'bulb out' from low LED current). On pre-97 XJ no BCM exists — straight relays — so usually no hyperflash. On 97-01 it can happen; add a 6 ohm 25W ceramic resistor across each turn signal LED if it hyperflashes.
- Brake-only LEDs are most straightforward; the third brake light (CHMSL) is also 1157 on most XJs.
Good options: Diode Dynamics XP80 1157 ($25 each), Philips Ultinon LED 1157 ($20 each), Sylvania ZEVO LED 1157 ($25 each). Whole-truck refresh runs ~$80-120 for tail, brake, CHMSL, and turn signals.
For an extra safety improvement, install a brake-light flasher module (Pulse Modulator) that flashes the brake light 3-4 times briefly when you press the pedal — significantly reduces rear-end collisions.
Why it works
- faster turn-on = safer
- less draw
- longer life
Trade-offs
- hyperflash on 97-01 sometimes
- cheap clones fit poorly
Tools required
- screwdriver
Parts
| Part | Vendor | Est. price |
|---|---|---|
| Diode Dynamics XP80 1157 (pair) | Diode Dynamics | ~$50 |
| Philips Ultinon Pro6000 1157 | Philips | ~$35 |
| Pulse brake flasher module | Pulse Brake Light | ~$30 |
Sources
Related
Written and maintained by an AZ wheeler and driveway wrencher. How we source guides. Always cross-reference your factory service manual — modifications affect vehicle safety and warranty. Work at your own risk.