Piston Slap: On the Edge From Poor Headlight Aim?

Sajeev Mehta
by Sajeev Mehta

Chris writes:

Hi Sajeev,

Love the column, it’s one of the things that keeps me coming to TTAC daily. I recently purchased a 2017 Ford Edge SEL AWD with the 2.0-liter Ecoboost. I love it so far but there is one glaring issue. The projector beam halogen headlights are simply awful, I can’t believe they left the factory this way. What are my options? Brighter Halogen bulbs, LED Bulbs or an aftermarket HID kit?

Help! I’m almost totally in the dark here!

Sajeev rambles:

Almost totally in the dark with Ford headlights? I remember that feeling, thanks to the tiny low beams with peeling chrome projectors on my 1995 Lincoln Mark VIII: useless after five-plus years of heat cycling. Luckily there was a factory HID upgrade (which I sorta wrote the book on)…

…and luckily for you there’s a man named Daniel Stern.

Daniel Stern actually answers:

The problem isn’t just in your head; take a look at how the 2017 Edge did in the IIHS headlamp tests. Don’t just skim, really spend some time studying the results for the optional HID and standard halogen lamps. They both got a poor rating, but for different reasons: the halogens gave inadequate seeing distance (and created some glare), while the HIDs gave excellent seeing distance — much more than what is considered optimal — but created a lot of glare.

It’s a little counterintuitive, but lamp aim — not bulb type or lamp technology — is by far the main thing that determines how well you can (or can’t) see at night. One thing about those IIHS headlamp ratings is that they don’t check or adjust the aim before testing.

They reason that most vehicle buyers never have their headlamp aim checked, and that’s correct, but it means the IIHS headlamp grades are a composite of how good or bad the lamps are, and how good or bad the aim is on the particular vehicle they test. Take a look at this analysis by one of America’s top vehicle lighting researchers. It’s dense and science-y, but the takeaway is that fully half the headlamps that got a “Marginal” or “Poor” grade would have got “Acceptable” or “Good” if they were aimed correctly.

So first, go find a dealer or shop that has and properly uses an optical headlamp aiming machine and see to it (babysit them as necessary) that the lamps are aimed carefully and correctly. Shining the lights on a wall is a very distant second preference; it really can’t get them closer than maybe the same state where the ballpark is located. Worse, many shops, and even dealers, just randomly crank the lamps up if the complaint is “I can’t see” or down if it’s “I get flashed.”

Read up on this here and see this informative VW bulletin on how to aim headlamps correctly. There are different brands of optical aiming machine, but they all work very similarly, and the same process is used on Fords, VWs, and every other brand of car; no other method is good enough. Most Fords have the VOR type of headlamp, though some have VOL, so whoever is doing the aim job needs to carefully check the headlamp lens markings and set the aiming machine accordingly.

After that’s done, think about the bulbs themselves. Two ideas (“LED bulbs” and “HID kits”) have to be taken out behind the barn and shot right offhand, because halogen lamps need to use halogen bulbs or they don’t, can’t, won’t work effectively, safely, or legally and can do extensive (and expensive) damage to the vehicle. See here for a lengthy dissertation on the how and why. The particulars are different for LED vs. HID, but the principles and problems are the same overall.

However, all halogen bulbs are not equal. Automakers put in long-life bulbs as original equipment, because Americans have this weird thing where they think the car’s a piece of junk if a consumable part needs to be replaced and the maker doesn’t give them a new one under warranty. (Amen to that. – SM)

But long-life bulbs put out dimmer, browner light and give poorer beam focus — that’s the tradeoff for the longer life. You can easily and inexpensively replace the long-life/low-luminance bulbs with high-luminance bulbs of the correct type to get brighter light and longer, wider beam coverage without endangering your car, your safety, or your warranty, but you have to shop carefully because the market’s full of bulbs claiming to be an upgrade when they’re actually a downgrade. A bulb promoted primarily with claims of producing “whiter” light, with blue tint on the whole surface of the glass, is a red flag; the blue-tinted glass blocks a significant amount of light that would reach the road without the tint. One major maker-marketer of that kind of bulb got swatted pretty hard some years ago for it, but there’s still a bunch of these blue-glass “whiter light” bulbs on the market.

The low beams on your car take an H11 bulb, and right now the best-performing H11 is this one from GE. Disregard the not-really-fraudulent-but-not-really-what-it-sounds-like use of the word “Xenon”; that’s a minor sin worth putting up with for this bulb’s better performance. It’s a certified, type-approved H11, so it’s legal and safe to use — nice to know in general, and it also means you can’t (by law!) be denied warranty coverage because of nonstandard bulbs. But do note the lifespan will be considerably shorter; you might have to change them in a year or even less, which is considered normal in Europe and Asia but can be a bit of a shock to Americans.

So try that first: a careful aim job and the best available bulbs. If the headlamps still aren’t good enough for your needs and wants, the only legitimate next step up is a big but costly one: swap in a set of the factory-optional HID headlamp assemblies. They look very similar to your present lamps, but despite common misunderstanding, the projectors they contain have completely different optics versus your halogen projectors; it’s NOT just a different bulb holder. Think of it like two pairs of the same kind of eyeglasses: they look alike, but yours have to have different lenses than mine if we’re both to be able to see.

The HID headlamps give a much wider, longer-reaching beam. They’ll be expensive from a dealership, but if you want to leave not even a tiny thread for future warranty claim denials to tug at, taking the car to the dealership and saying, “Install the factory optional HID headlamps” will achieve that.

The other option is to find a like-new perfect set of used ones via www.hollanderparts.com or www.car-part.com . Still genuine factory parts, much less expensive, and with friendly smiles from you and your dealer service writer you might still get ’em installed by a Ford technician. Note that the vehicle’s body computer may have to be flashed to recognize and correctly operate the HID lamps, and they’ll have to be aimed carefully as described above.

[Image: Ford]

Send your queries to sajeev@thetruthaboutcars.com. Spare no details and ask for a speedy resolution if you’re in a hurry…but be realistic, and use your make/model specific forums instead of TTAC for more timely advice.

Sajeev Mehta
Sajeev Mehta

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  • Chris Chris on Jan 30, 2018

    OP Here! Thanks for the excellent info Sajeev and thanks everyone else for the thoughtful discussion. I'm going to start by asking the dealer to check the aim when I'm next in for service. If that doesn't help I'll be ordering a set of GE Nighthawks. Looks like a pretty simple job to change the bulbs.

  • 28-Cars-Later 28-Cars-Later on Jan 30, 2018

    Excellent piece Mr. Stern. I do wonder though, how difficult is it to service the light bulbs on this model?

  • Lorenzo Subaru had the ideal wagon - in 1995. The Legacy Outback was a straight two-box design with rear quarter and back windows you could see out of, and was available in brown with a 5-speed manual, as God and TTAC commenters intended. It's nice they're not raising prices, but when you've lost the plot, does it matter?
  • Bkojote Remember a month a go when Cleveland wanted to create a more walkable Cleveland and TTAC's 'BIG GOVERNMENT IS THE PROBLEM' dumbest and dullest all collectively crapped their diapers? Here's the thing- look on any American highway and it's littered with people who don't /want/ to be driving or shouldn't be. Look at every Becky on her phone during the morning commute in her Tucson, look at every Brad aggro driving his 84 month loan GMC. Hell look how many drivers nowadays can't even operate a headlight switch. You expect these people to understand a stoplight? In my neighborhood alone 4 people have been rear ended at lights from someone on their phone. Distracted driving over the past 10 years has spiked, and it's only going to get worse unless Becky has an alternative, because no judge is going to pull her license when 'she needs it to get to work!' but heaven forbid she not check fb/tiktok for 40 minutes a day.
  • Scott Shouldn't the The Italian Minister for Business be criticizing The Milano for being too ugly to be Italian?Better use of resources doing that....
  • Steve Biro Frankly, while I can do without Eyesight and automatic start-stop, there is generally less B-S with Subarus in terms of design, utility and off-road chops than with many other brands. I just hope that when they adopt Toyota’s hybrid system, they’ll also use Toyota’s eCVT.
  • The Oracle These are all over the roads in droves here in WNC. Rarely see one on the side of the road, they are wildly popular, capable, and reliable. There is a market for utilitarian vehicles.