Sealed Beam Headlights

If you’ve landed on this page, you could say you’re one of the lucky ones that doesn’t have yellowed headlights. That’s the good news. The bad news? Your lights still likely suffer from reduced output, and they’re designs that haven’t changed in 30 years or more.

There is some good news however. There are LED replacement assemblies available for most of them, from either Truck-Lite or JW Speaker. There’s lots of other stuff out there, but in terms of meeting Federal Motor Vehicle Safety Standards, performing reliably, and not causing unacceptable glare for other drivers, these are the only two brands to consider at this point. Both make all of their LED headlamp replacements in the United States.

Back to bad news for a minute. They’re not cheap. The Speaker lights tend to be significantly more expensive than the Truck-Lite lights, but are a significantly better light. They are also visually aim-able, which means you don’t need any special aiming tools when you install them.

In some cases, particularly with the 2D1 (7″ round) format, some trimming of the headlight bucket will be necessary. The standard, despite its age, still lacks a key interchange dimension.

Generally steer clear of kits to adapt a sealed beam system to replaceable bulbs. Most of these kits are cheaply made, and will not be a significant improvement. Steer clear of advertisements with “DOT approved” or “for off-road/show use only” language–DOT doesn’t approve anything, and the off-road disclaimer is essentially an announcement that sales of the product is illegal in the US.

A few notes on nomemclature:

First digit (e.g. the 2 in 2D1) in the identifier on the headlight lens indicates the number of filaments in the bulb–2 indicates 2 filaments, providing low and high beam, 1 indicates a single high-beam filament only. If you have 4 headlights, you should have 2 dual-filament lights and 2 single-filament lights.
The trade number is the part number you’d find on the box at the auto parts store. A leading H indicates a halogen capsule. If you have any bulbs without the H, or if you can look into the light and see a filament not inside a small capsule, replace those ASAP! Those are ancient, and will be significantly outperformed by the $10 light at the local parts house.
If the trade number has a line through it below, that’s a reduced output bulb. Even an upgrade to the newer halogen replacement will be an improvement.