Auto Q&A: Adjusting low-beam headlights
Can this be done at home?
Q: We have a 2017 Nissan Altima and are trying to figure out how to adjust the low beams. We replaced the entire headlight assembly on our 2007 Toyota Highlander and were able to adjust the beams without a special tool. However, all online searches for the Nissan indicate the car has to be taken to the dealership for adjustment. Can you help with instructions on how this could be done at home?
–Steve and Cindy
A: Adjusting your headlight housings for proper alignment is possible at home if you can find a long, truly level area with a vertical screen such as a garage door. (Note: Truly level pavement is hard to find!)
Here are Nissan’s recommendations before any inspection/adjustment is performed:
Remove any cargo; make sure spare tire and jack are properly stowed; fill the fuel tank; set tire pressure to the specified value; bounce the front and rear of the vehicle to settle it; set the front wheels straight; add a 150-lb. driver or equivalent.
Next, measure from the ground up to the center of each low beam headlight bulb and transpose this height to the screen using a horizontal stripe of masking tape. Add two additional horizontal tape lines at 1 inch and 2 inches below the headlight height.
A more generic method is to drive up as close as possible to the screen and mark a horizontal and vertical line with masking tape where the center of the low beam light strikes the screen (easier and possibly more accurate). The Altima is then backed up 33 feet from the screen (this distance varies between car makes). Block one headlight alternately with cardboard or a towel and observe where the remaining beam strikes the screen. The most intense projected spot should fall between the two lower marks (very slightly downward from level).
Vertical adjustment is possible via a screw down low on the back side of the housing, roughly centered between the two lamp sockets (screwdriver comes down vertically to meet the screw). Horizontal adjustment is not possible.
I should mention that states may have differing alignment specs, and some headlight housings contain a bubble level, which is typically centered as the car is parked on a level surface.
Q: I sometimes hear a roaring sound from my truck’s engine when climbing a long steep hill during warm weather. What is it?
–Colin
A: Most likely you are hearing your thermostatic fan clutch engage. Vehicles with longitudinal engines and a mechanical fan are typically equipped with a fan clutch, allowing the fan blades to lumber along at reduced rotational speed during normal driving. This reduces load on the engine and saves fuel (a large/aggressive fan can require as much as 30 horsepower to turn it at high speed when directly coupled).
When climbing or pulling hard, and the engine temperature rises to perhaps 220 F, the fan clutch engages, eliminating any fan blade slippage. The roar you hear is the fan really taking care of business! As temperature drops, the clutch will release and allow the fan to fall back to a normal pace.
At first sign of steering wheel wobble, fix the damper
By Bob Weber, Chicago Tribune
Q: I purchased a used 2019 Ford pickup with 11,000 miles on it. As I was driving on I-80 at 70 miles per hour, suddenly the front end started to vibrate. I was able to pull over. The next day while driving 55 miles per hour on a 2-lane highway, the truck started to vibrate so badly that the steering wheel pulled out of my hands. The next thing I knew I was in the other lane; fortunately, no one was coming. We still had 50 miles to get home, so I drove about 35 miles per hour.
I called the dealer and they said Ford knew about it but did not issue a recall. It’s the steering damper and they will not have a replacement part for about two to three months. The dealer had to put in an aftermarket part.
— R.Y., Varna, Ill.
A: Steering wobble goes back as far as 1965 when Ford introduced the twin I-beam front suspension and steering dampers (stabilizers) probably go back as far. Like a shock absorber, the damper can wear out or suffer damage. I have heard rumors of a class action suit for the wobble issue. I encourage readers to replace the steering damper at the first sign of wobble.
Q: I use a tool with a swivel on my car’s windshield to clean it. It really works, but I have yet to find a product that will remove the film on the inside of the windshield. Can you help? I have tried all the standard products.
— Addison, Ill.
A: That insidious film comes from outgassing. Much of it comes from the vinyl on the dash, but there are plenty of outside sources. The newer the car, the quicker the film returns. I prefer to use automotive glass cleaners such as Invisible Glass, Meguiar’s or others. After repairing a bulls-eye chip on my windshield, the Safelite tech gave me a can of the company’s cleaner, which also did a good job. Household cleaners don’t seem to work as well.
Tip: after cleaning the glass, polish it with a dry microfiber cloth or crumpled-up newspaper. Don’t try this with a digital newspaper, though.
Q: I own a 2018 Jaguar XF Sportbrake (wagon). At my last service in December 2019 with 20,538 miles on the odometer, the service manager recommended that I need rear brakes soon. I never owned a car that needed the brakes (rear or front) replaced until at least 50,000-plus miles. As a matter of fact, my wife’s Mercedes CLK 350 is running 70,000 miles and still has the original brakes.
The service manager said that it is very common for Jaguar vehicles to need new brakes between 20,000-25,000 miles. Is he just trying to make some quick money off me ($900 is the cost) or is there any truth to this, and why the rear brakes? I usually have had to replace the front brakes first.
— F.H., Allentown, Pa.
A: The front brakes do most of the braking, even more so on front-wheel-drive cars. So, you are right in suspecting something sounds fishy. Take your vehicle to another shop, perhaps an independent repair shop, and ask for an inspection. You may discover that it’s a little diagnostic money well spent.
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