As people keep their cars longer, oxidation of commonly used plastic headlight lenses is an increasing problem for drivers, warns Consumer Reports.
Oxidation creates a haze that’s not only unsightly but that can significantly reduce headlight illumination, creating a safety hazard. And because hazing occurs over time, drivers might not notice the creeping danger. Hazing can also be more prevalent on vehicles with higher levels of UV exposure.
Replacing the lenses or having them professionally cleaned are options, but that can cost up to $200. For a fraction of that, you can use a headlight lens cleaning kit.
CR sampled four kits, all costing $21 or less, on several older cars. All the kits remove the cloudy surface of plastic lenses by using abrasives. Three then polish the lenses back to a smoother finish, while a fourth skips directly to the sealant stage to finish the lens. Two other kits also use a sealant. All can be purchased either online or at auto parts and department stores.
CR evaluated each kit for effectiveness and ease of use. Testers used a light meter to measure output from the headlights before and after using each of the products. Then they retested light output from the headlights eight weeks later to see how well the cleanings held up over time.
Testers also noted the difficulty, number of steps and time required to use each product. The results varied, but testers found that even the poorest performer in the group can dramatically improve light output on badly weathered lenses. You have to do a thorough job, though, for the best results.
A small percentage of lenses have a hard protective coating that must be sanded off before refinishing takes place. One kit, by Sylvania, was able to remove the hard coating with the supplied materials, but the others required buying 400-grit emery paper.
CR’s findings include (listed in performance order):
Sylvania Headlight Restoration Kit ($21). Six steps. Most improvement with no degradation over three months.
3M Headlight Lens Restoration System 39008 ($15). Four steps. Great improvement with no degradation. Requires an electric drill.
Turtle Wax Headlight Lens Restorer ($9). Six steps. Great improvement, but sealant wore away within two months.
Fast Brite Auto Headlight Restorer Kit ($17). Two steps. Easiest to use, least improvement. Sealant wore off within two months.
Bottom line: The Sylvania Headlight Restoration Kit provided the best and longest-lasting results. The 3M kit, though trickier to use, provides similar performance at a lower price. The Turtle Wax kit costs less than half the cost of the top-performing Sylvania. But neither the Turtle Wax nor the Fast Brite, a kit marketed through infomercials, held up as well as the other two.
Detergent doses: “ultra” confusing
Although today’s washers have made doing laundry easier than ever, concentrated laundry detergents have not. Some claims are puzzling, measuring cap sizes are all over the place and if manufacturers really wanted to lighten your load, they’d make it crystal clear how much detergent is needed to get the job done.
Concentrated detergents -- 2x, 3x and even 8x -- have less water (and other nonessential ingredients) than conventional products, and packaging is smaller, so less plastic and cardboard are used and transport is more efficient. The x’s don’t have a standard definition, according to Procter and Gamble, Tide’s maker, but they’re usually linked to a previous formula, so 2x would give equal performance for half the dose.
But the benefits go down the drain if you use too much detergent. That’s easy to do. Some of the caps’ fill lines are hard to decipher, and the line for the largest load may be only halfway up the cap.
Bottom line: Until caps are crystal clear, CR recommends following label directions. Use a marker to highlight fill lines, and measure, don’t just pour.