Left to right headlight adjustment

For a while my headlights have been aimed slightly too high and finally got around to lowering them today. The vertical adjustment went fine, parked on a flat surface ~20 feet back from a wall, marked the center of my beam, lowered them etc.

While doing that I noticed my drivers side headlight is aimed slightly left of where it should. Based on previous TW threads I found the left/right adjustment knob (above the black rubber boot that covers the bulb) and gave it a couple half turns with no noticeable change. Then I threw caution to the wind, and gave it several full turns and still did not see any change. No amount of turning seemed to adjust my lights left/right.

Has anyone else ran into this problem? Or is there something I’m missing?

Appreciate any insight on this. Cheers

 

Jimbo, did you intend to add a link to that? Not sure what you mean by post "here".

Is there somewhere else I should've posted this question? New member.

Thanks

 

https://www.tacomaworld.com/threads/the-ultimate-headlight-upgrade-h4-not-led-or-hid.398066/unread

Pretty sure he goes over adjustments at the beginning of the thread. Also pretty sure he recommends not adjusting for left and right.

 

Roger that - will have a read through. Thanks

 

I've tried to adjust the right/left on an old set I had on the truck with no luck. The OEM set I currently have is okay but would be better with an adjustment, so I'm here for the learning. I didn't touch the right/left adjustment on these.

 

The Left/Right adjustment is very difficult to perceive because there isn't a cut off like the low beam vertical adjustment. You are trying to judge an intensity shift within a highly lit area, something human eyes are going to be very poor at doing. So a few degrees of change isn't noticeable to your eyes on a static wall, but at distance it will significantly throw off your headlight aim. By the time you've adjusted the lights enough horizontally to visually notice, you've really fubared your headlight aim, bad. What's worse, it is extremely difficult to recenter. The reason the horizontal aim screws are covered by Toyota is that they should not be needed assuming your frame is square.

Should you have made the mistake of adjusting the horizontal aim, the best way I have found to fix it is pull the truck 90 degrees square to a wall with a large perfectly flat area. Pull the truck up so the wall so it is inches from the wall with the lights on. Mark the hot spots with tape on the wall. Then back the truck up slowly perfectly perpendicular to the wall with the lights on. If your lights are square as they should be the taped hot spots will continue to stay directly on the tape spots, indicating proper aim. If they are misaligned horizontally, the hot spots will drift to the sides indicating bad horizontal aim. If so, correct the horizontal aim accordingly and retest.

 

Brought mine in to a shop to do an alignment on the new headlights after install...$49.99

I tried to set them up myself, but just couldn't get them right.

 

Thanks Crash! I appreciate the in-depth response.

I recently installed LEDs in the OEM reflectors so the low beam is very concentrated, which would have made any change even less noticeable. Now that I know about your ultimate headlight upgrade I'm going to go that route instead and will have to do my best to readjust horizontally.

 

scarfhater....I was not commenting on where you posted. I commented because I too have had the same problem and wanted to create a post for two reasons. 1. to follow this conversation. 2. to empathize with your situation. In my case, I have yet to bottom out the horizonal adjustment, but I know they are not perfect. Next time I am near a big wall at night, I plan on messing with it a bit more.

 

After tinting my headlights, the stock bulbs were not throwing light very well. I didn't do all of the wiring that the ultimate headlight upgrade suggested, but I did put in the higher wattage bulbs and there was a considerable difference. My understanding is that the stock headlight wiring can easily handle the increased wattage. And, the difference when decreasing the wire gauge would be barely noticeable if at all. So, I opt'd for the easy route. Just switch out my bulbs. Although, my passenger side clip came off while doing the switchout and I found there's a whole other thread about that too. I love this place.

 

I wish I had listened to that advice.

 

The halogen upgrade is definitely the way to go. Despite aftermarket companies pushing pnp LEDs, they are not optically compatible and performance will be poor, typically with more foreground light, less distance light and more glare.