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7/29/22: Today I took my truck to it’s mandatory NY State inspection, and get my headlights adjusted. It’s about a 15 miles each way, so she gets a little work out. Just after the owner finished the inspection (passed with no issues), he handed me the bill. I said that I also needed the headlights aligned. He told me he hasn’t performed an alignment since NY dropped the requirement and he no longer had the equipment. I know that in the past, I would just pulled the vehicle in front of a wall and was able to do a semi-quasi job. I checked the Shop Manual and the instructions said to park the truck 25’ away from the wall and with high beams on, center should be 3” lower than the center of the light itself. That is a problem for me, as I don’t have a flat spot anywhere in my driveway so I needed a different strategy.

My iPhone has an inclinometer built into it, so I thought I may be able to use that. I removed the headlight bulbs so I could span the bulb holder. The phone is not large enough to span the distance so I taped the phone to a combo square. I initially placed the square (with phone attached) on the floor as my floor is slanted toward the garage doors. Adding 90 degrees to that would theoretically give me perfectly parallel aim. Since the light beam needs to be 3” lower over 25’, I needed to figure out in degrees how much a 3” drop over 25’ was. Using an online calculator, it worked out to be .6 of a degree. Adjusting the light to show approximately 1/2 of a degree should get me in the ball park.

Adjusting side to side was even easier. I placed about a 6’ 2x4 across from one light to the other and again using my iPhone with a compass app, showed it as 136 degrees. All I had to do was adjust the individual lights to 136 degrees and they should be perfect (in theory anyway). Being that the adjustment screws are working off of three points, I needed to readjust a couple of times. Depending on how accurate the inclinometer is in the iPhone, will determine the results. I’m going to a local cruise-in tomorrow evening, so I’ll let you know the results!