I created Piston Slap as a way to bring the diverse knowledge base of your favorite car forum to the autoblogosphere with easy to digest weekly posts. The only problem is when a mistake gets published, the thread never comes back to page one with its correction.
I screwed up, so here I’ll do my best to fix it: I was mistaken about aftermarket DOT/SAE approved lights being just as good or better than original-equipment factory parts. Some of the aftermarket parts are promoted as being “CAPA certified” (Certified Automotive Parts Association), but as we shall see, that doesn’t mean what it sounds like, and it doesn’t help with our reader’s query that started the conversation in the first place. As seen elsewhere, parts not up to spec can have tragic consequences with little recourse for victims.
So let’s hear it from The Man himself, Mr. Daniel Stern, who writes:
If at all possible, replacement headlamps really need to be genuine, original-equipment items — the automaker’s own brand or that of the original supplier to the automaker. All of the aftermarket off-brand items (TYC, Depo, Anzo, DJAuto, Eagle Eye, Helix, Sonar, etc) are junk, whether they’re OE-lookalikes or restyled with clear lenses, projectors, halos, etc. The low price is attractive, but their quality, performance, and durability are all substantially and often dangerously inferior to the genuine lamps.
There is little or no real optical engineering behind any of the aftermarket lamps — they are headlamp-shaped toys made from physical copies of the originals, which is not even close to adequate. One might as well try to cast new working contact lenses from a mould of your originals and expect to be able to see when you put ’em in your eyes. Even basic, low-tech headlamps are more akin to optical instruments than to the lamp on your bedside table.
The level of shape accuracy required to accurately focus a headlight beam can only be achieved with precise optical engineering from scratch, using correct materials with tightly controlled manufacturing and quality control. All of those things are missing from the knockoffs, which don’t even begin to get in the ballpark. Light distribution is not what it should be, and often the DOT certification marks are fraudulent.
“Perfect OE fit and performance” is often promised in the ads for the copycat lamps, and more recently they’ve been babbling about “CAPA certified” and “NSF certified” lamps, both of which are meaningless but sound impressive. (They’ve also been charging extra money for these bogus certs, and that’s not the only pricing game they’ve been caught playing.)
The thing about “OE fit and performance” is a big belly-laff; take a look at this large test by the US Department of Transportation of original equipment vs. TYC and Depo versions of simple, American-vehicle headlamps: damn things don’t even fit the car correctly, let alone come close to performing the way they’re supposed to. What is this CAPA? It’s the Certified Automotive Parts Association, an aftermarket-crash-parts lobbyist group that works hard to make sure your insurance company can stick you with inferior parts when they repair your car after a crash.
So exactly what is being “certified” then? CAPA’s criteria for lamp certification, called CAPA 301 QSM Section 12, concentrates heavily on the appearance of the lamp: it has to look substantially the same as the original lamp (minus trademarks belonging to the automaker, of course, because we’re talking about unauthorized parts here). CAPA’s criteria do not require that aftermarket lamps operate the same as the original lamp they’re replacing in terms of performance, durability, weather resistance, vibration resistance, or anything else. The only performance requirement is that the lamps must comply with Federal Motor Vehicle Safety Standard 108 (the US federal regulation for car lights) — which is not much of a requirement at all, given that a $4 sealed beam and the multi-thousand-dollar full-LED headlamp on a Cadillac Escalade Platinum both meet FMVSS 108. Wanna see what this kind of aftermarket “compliance” looks like in the real world? Take a look at Ryan Ridgley’s comparison of genuine and knockoff Volvo 240 headlamps.
Fine, so “CAPA certification” is a smokeshow, but doesn’t saying the lights are “DOT/SAE approved” count for anything? No. It sounds official but also means nothing; there is no such thing as “DOT approval” or “SAE approval.” SAE is not a regulatory body; their technical standards don’t have any force of law except to the degree that the U.S. government adopts them. FMVSS 108 contains bits and parts, often modified, from current and obsolete versions of various SAE standards, but that’s as far as SAE involvement goes. Neither DOT nor SAE approves vehicles or equipment.
The “DOT” marking on a headlamp does not mean the DOT or anyone else in any official capacity has scrutinized or tested the headlamp and judged it good. That’s not how it works in North America. Instead, we have a system called “self-certification.” The maker or importer of a vehicle or item of regulated vehicle equipment (such as a headlamp) proclaims an item meets all applicable standards. That’s it. The “DOT” mark on the lens just means the maker or importer says, “I promise it’s OK.” If reams of complaints, a pile of twisted metal, or maimed bodies accumulate to point in the direction of maybe a noncompliant headlamp, then the DOT might open an investigation. If they find the headlamps are noncompliant, they can try and force the maker or importer to recall them. But take a look at what happened to that importer-distributor of Chinese tires some years ago: they sold a mountain of fraudulently DOT-marked tires, a bunch of crashes happened, people died, DOT eventually levied fines and ordered a recall, the Chinese tire company weaselled out of any responsibility, and the American importer-distributor went bankrupt. So sorry, won’t be able to pay those fines or recall those tires, we’re bankrupt.
Back to headlamps: on an older-model vehicle for which genuine lamps cannot be bought any more, one has no choice but to hold the nose and try to buy the least-worst aftermarket lamps. It’s a crapshoot, and you’re not going to get a lamp as good as the originals, but this is one of the unfortunate consequences of the end of the sealed-beam era when all cars used standard-size headlamps: eventually all the original headlamps for a given model are used up, no more are available, and “better than nothing” is the best you can do. In that case, you pretty much have to pick by track record; Dorman has a pretty good reputation for standing behind its stuff. But if you can get original lamps, that’s definitely best; even for vehicles that have relatively low-performing original headlamps, the genuine lamp is almost always substantially better than the knockoff stuff.
Lamp aim is by far the main thing that determines how well we can (or can’t) see at night with any given set of lamps, so they’ll need to see to it that the lamps are aimed carefully and correctly, preferably with an optical aiming machine per the instructions here. Our reader’s lamps are the “mechanical aim” type.
As Sajeev mentioned, each headlamp takes a 9007 bulb. The best 9007 bulbs presently on the market are the GE Nighthawk Xenon (“Xenon” is probably the most-abused word in the vehicle lighting world) or the Philips Xtreme Vision. Skip the “extra white” bulbs (Silver Star, PIAA, and dozens of other brands); they’re a scam. And halogen lamps need to use halogen bulbs or they don’t work right; “HID kits” and “LED conversions” are unsafe, ineffective, and (therefore) illegal.
Even with new, legitimate headlamps and the best bulbs, it’s still gonna be hard to see well at night until they fix the severely underspecified headlamp wiring that starves whatever bulb is at the end of the wires. That can be done on a DIY basis or with a ready-built harness. It can also be done with a cheapy $40 “universal” harness consisting of thin wires and unreliable no-name relays. But if that’s the choice, it’s better to live with the limitations of the stock wiring — inadequate but basically safe — rather than running the real risk of sudden light failure when the cheesy harness gives it up the ghost in the night.
Send your queries to [email protected]