CarTalk.com Best of Deals Car Reviews Repair Shops Cars A-Z Radio Show

Replacement headlight manufacturers

Sylvania claims “Brighter light is as easy as upgrading to SilverStar? bulbs . Up to 35% brighter, up to 30% more downroad visibility and up to 35% more sideroad visibility.” I can really use more side vivibility for making left turns at night in my '99 Suburu Forester. But Sylvania also says,“Claims based on measured comparisons between SilverStar and SilverStar Ultra product families at 100% light output and standard halogen bulbs at 80% light output. Actual performance may vary by product use, vehicle model and usage.” Do you think their new lights would help my '99 Forester in cornering visibility?

That bulb does appear to give an improved output compared to the standard bulbs of various brands. Of course cleaning the lenses is usually the best place to start when the headlights are not functioning up to expectations.

Keep in mind that light efficiency is related to lamp life.  It is not hard to get more light out of any tungsten type lamp, just by increasing the voltage.  However the price you pay will be shorter lamp life.  In many modern cars, you also risk heat damage due to the lamps.

It is well known, and is in fact, indicated on Sylvania’s website, that these lamps have a lesser lifespan.

Are the lens’ fogged up or yellowed. If so buy new ones off ebay. You loose a bunch of light when they are not clear.

I agree with replacing the headlight assemblies. Checked eBay, about $165 for the pair there. We own a 1999 Outback and the lenses are very yellowed.

You missed the fact that their up to 35% more light claim is their brand new same wattage bulb vs your old worn out bulb operating at 80% of its original light output.

New, regular type bulbs will provide just as much light in comparison to old, worn out bulbs.

BC.

“New, regular type bulbs will provide just as much light in comparison to old, worn out bulbs.”

I know that used to be true with sealed-beam headlamps. The tungsten would boil off the filament and slowly deposit itself on the glass, darkening the lamp on the inside.

But is it still true with halogen bulbs? The halogen gas prevents this from happening and very little if any of the filament material is deposited on the glass. Halogens typically look as bright as day one until they burn out in my experience.

Well, they’re comparing used bulbs at 80% output to new at 100%, so they’re guaranteed a 25% boost right there, just by replacing the bulb. They only have to get 10% more from the SilverStar over stock to meet their claim.

A lens cleaning kit will restore your yellowed and cloudy lenses to like new condition which will make a big difference…

There still are deposits from the filament on the glass over time.
The bulbs have to reach a certain temperature before the full recirculation takes place, and once the metal is mixed in the inert gas, that is what is deteriorating the actual amount of light, as it obstructs the light while in gaseous form.

A brand new bulb doesn’t have nearly as much material in gaseous form yet.

BC.

Even with recirculation (and uneven re-deposition) halogen lamp filaments get thin spots over time and the overall filament resistance increases, reducing light output slightly.

Both quartz-halogen and “old style” bulb create light by heating a tungsten filament until it glows. The difference is that quartz-halogen bulbs use a different inert gas that allows the filament to be heated to a higher temp without quickly failing. The fused quartz simply withstands the higher heat better than traditional glass bulbs. Both are primarily silicone dioxide, but fused quartz has far fewer impurities.

Outgassing and deposition adversely affects transmission characteristics of the bulbs, but the big culprit is the change in grain structure in the tungsten filament, and that affects all incandescent bulbs, of which a quartz halogen bulb is one.

In short, all filament bulbs lose light output with use. New bulbs of the same type will always put out more light than old, much-used bulbs.

Bulbs like “SilverStars” put out more light by heating the filament hotter, at teh expense of filament life. They work great, but need to be changed more often.