Headlight aim drops after washboard road

[pluton]

Anyone ever had this headlight malady?
After driving maybe a few hours on rough(embedded rocks and washboard) roads, my 97's left headlight aim drops down from normal to where it's aimed at about 8 feet in front of the truck.
Never happens in normal street/highway driving.
If you have had this happen, did you fix it or replace the headlight unit?
The right headlight is unaffected.

 

[rallypoint_1]

Check if the clips holding the headlight are broken. It's a plastic piece where the adjuster is if I remember right. It's a plastic ring that holds it still.

 

[pluton]

It appears that a course-threaded metal screw that is threaded into brittle plastic (thanks, Toyota) works itself loose under "severe" vibration.
Here is 1)the location of the screw behind the left headlight, 2)the vibration backed-out screw. I screwed it back in with JB Weld glopped onto it, pending headlight replacement.

 

[Tyler James Inc]

Yep; same thing happens in my '97. Passenger side on mine.
I'm replacing the headlights soon, so haven't gone through the trouble of epoxying the stud back in.


Sent from my iPhone using Tapatalk

 

[StreetCreeper]

Well shit! For the last couple of weeks I've been looking at my driver-side headlight beam and thinking that it seems lower than it should be. Being lazy and usually not in my right mind, I've been telling myself it was just my imagination.

Then low an behold this thread...

I'll go check it tomorrow

 

[pluton]

It is extremely annoying to screw this thing back because of interfering protuberances from the headlight structure. I had to use a 1/16th inch thin Park Tool 10mm wrench originally sold for bicycle use.
I wonder if they changed this design/part on the later 99+ 'clear front' headlights?