I had a low beam headlight go out last year so I replaced both with sylvania silverstar ultra H11's.
Good on replacing the complete pair, rather than just doing one at a time. Not so good on the bulb selection, unfortunately. Sadly, marketing is so much more effective than their bulbs.
They didn't last long so I replaced them again with the same thing, went out again and then read on the back of the package they were only rated for 150 hours.
They're rated for such a short life because the filament changes required to make such a blue-tinted bulb still produce the legally-required amount of light will severely shorten the bulb life.
I'm looking at Phillips H11 X-treme vision. They have 300 hrs run time.
Philips X-Treme Vision doesn't play the "let's tint the whole bulb" game, and therefore has a filament that may be shorter-lived than a
standard bulb, but will greatly outperform it *and* outperform the SilverStar Ultra.
It might be time for new factory headlamps-- the 10-to-11 year old lamps you have may have outlived their usefulness. You might also need to do a voltage drop test (see
here) because the wiring may also have degraded. Whether you get new lamps or not, be sure to
aim them correctly.
Led upgrade that isn't too expensive?
Unless the '07 LaCrosse (or a sister car) had an LED option (in which you could just buy that model headlamps and install them), no. There are no LED "upgrades" for headlamps short of taking a different
complete LED headlamp unit and attaching it to the car, or removing the composite headlamps and attaching the likes of JW Speaker or Truck-Lite "sealed beam"-shaped LED replacement lamps (which could make the car look rather goofy, but would be safe if you attached them securely enough and aimed them properly).
(In your previous post, I had to edit a bunch of color tagging and "viglink" tokenized URLs. If you copied this post from a post you'd made on another message board, be advised many of those 'other' boards will take keywords and make links out of them to try go get hits from unaware people.)