Aiming Headlights Procedure?

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NCBurb

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Howdy. 87 Suburban with all stock lights as far as I can tell. Got home from work a few days ago and noticed one of my headlights was looking down at the ground at an ugly angle. I pulled the cover trim and found one of the adjuster screws just dangling, looks like the dinky plastic clips that hold them in place had disintegrated. I ordered a set of 8 figured I might as well replace all of them at once instead of one at a time.
I was wondering if someone can point me to guidelines for properly aiming the headlights once all the adjusters are replaced. I have done this on other vehicles and it's always something like park 20 feet in front of a wall, aim for a line 3' up or something like that. If anyone can share those exact specs with me I would appreciate it.
Thanks,
 

SirRobyn0

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Howdy. 87 Suburban with all stock lights as far as I can tell. Got home from work a few days ago and noticed one of my headlights was looking down at the ground at an ugly angle. I pulled the cover trim and found one of the adjuster screws just dangling, looks like the dinky plastic clips that hold them in place had disintegrated. I ordered a set of 8 figured I might as well replace all of them at once instead of one at a time.
I was wondering if someone can point me to guidelines for properly aiming the headlights once all the adjusters are replaced. I have done this on other vehicles and it's always something like park 20 feet in front of a wall, aim for a line 3' up or something like that. If anyone can share those exact specs with me I would appreciate it.
Thanks,
You have the basic idea right. But on flat ground in front of a wall. This is how we do it at the shop, and we use the garage door. Pull as close to the wall as humanly possible without touching and leaving you enough room to reach in front of the lights. Turn the lights on and mark where the beam hits the wall. Back the vehicle up 25' in a straight line, the top of the main part of the beam of light should be at or slightly (1 inch or so below) the mark you made, and they shouldn't be shooting off to the side. Alternatively you can measure to the middle of the headlight and then measure that height on the door, but you will have no accurate way to do right and left alignment then.

It seems no matter how careful you are that will give a close but not perfect alignment and you might feel the need to pull up on a quiet road at night, especially if it has lines on it, to even out the height and side to side a bit.

Back in the day there were tools made, called headlight alignment tools or machine that would dial them into perfection, but for the most part those tools are gone and what is left is either broken down or ridiculously expensive.

Just realize that no wall alignment method is perfect and be prepared to tweak it a little afterwards.
 

shiftpro

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I like a lonely road at night. A piece of cardboard I hang with tape over one light at a time. Drivers i like to aim at the center line or just inside. Passenger further up and on the white line.
 

TotalyHucked

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You have the basic idea right. But on flat ground in front of a wall. This is how we do it at the shop, and we use the garage door. Pull as close to the wall as humanly possible without touching and leaving you enough room to reach in front of the lights. Turn the lights on and mark where the beam hits the wall. Back the vehicle up 25' in a straight line, the top of the main part of the beam of light should be at or slightly (1 inch or so below) the mark you made, and they shouldn't be shooting off to the side. Alternatively you can measure to the middle of the headlight and then measure that height on the door, but you will have no accurate way to do right and left alignment then.

It seems no matter how careful you are that will give a close but not perfect alignment and you might feel the need to pull up on a quiet road at night, especially if it has lines on it, to even out the height and side to side a bit.

Back in the day there were tools made, called headlight alignment tools or machine that would dial them into perfection, but for the most part those tools are gone and what is left is either broken down or ridiculously expensive.

Just realize that no wall alignment method is perfect and be prepared to tweak it a little afterwards.
This is exactly how I do it on everything, modern or classic. This will get you very close. Depending on the lights (like the junk OE's I still have in my square), I'll adjust them slightly higher to get a little more throw. I might do that a couple times till I'm happy with it running down back roads and if I start getting flashed, I'll bump them down just a smidge. It's not really an accurate process, just a game ya gotta play till you find that happy medium.
 

Matt69olds

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Find a wall with at least 25 feet of level ground. Put the truck with the bumper basically touching the wall, turn on the light. Put a mark in the center of each headlight circle. Back up 25 feet, aim both headlights so the center is one foot down, and aim the drivers in 1 foot to the pass side. The idea is to set the drivers headlight towards the pass side so you don’t blind the oncoming traffic
 

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