Anyone change a headlight on a 579?

I drive a 2020, maybe it has changed for a different year. I am not with the truck today so I can't tell you if it's the top or bottom for sure but I seem to remember it being the top where there is a thumb knob or screw in the center that you undo and the the bottom holds itself in with tabs.

Unscrew the knob and remove it so you can grab the top and pull it up to remove it.

 

Maybe this is the same (close to) set up.

 

Spray the thumbscrew with lubricant if you can .. as a Canadian ours rust in place if you don’t . Ps I’d often put the threads in excess grease from fifth wheel before reinstalling.

 

Model 579 Under the Hood & Bulb ReplacementYouTube · Peterbilt Motors Company1 minute, 18 secondsOct 15, 2020

 

Every time we pull those covers we lather up the thumb screws with anti-seize which definitely helps but sometimes they still get stuck and you end up stripping the plastic part off of the screw. Then it's time for the locking pliers, bad design if you ask me.

 

Those thumb screws are a regular maintenance item. I regularly dip mine in engine oil.

 

On my old truck I had to use channel locks to turn that thumb screw. They catch a lot of grit and don’t turn easily if you haven’t opened it for a while.