They are as clear as can be. I have no way of knowing for certain that they are O.E. Chrysler parts, but they sure look exactly the same as every other truck out there from that generation.
The lens markings will tell you right away if they're not genuine parts (brand names like TYC, Spyder, Spec-D, or DEPO); or possibly they're counterfeit lamps but that isn't extremely likely.
It's purely subjective, but lacking any actual equipment to be scientific
Yes, it's subjective. And particularly with headlamps, subjective opinions differ greatly from objective fact.
The driver's side was clearer and brighter. Years down the road now, I think that may not have been due to the new bulbs being any better, but simply comparing a new bulb to a many years old one.
Bulbs degrade with age, both in lumen maintenance and in beam focus. If you look closely at a well-used but still functional bulb, the filament will have both pitting and dendritic growth, from bits of filament flying off and reattaching from the halogen cycle.
I'm starting to wonder if I had replaced one bulb with a new O.E. bulb, if it would not have also seemed to be brighter.
It would have been both more intense and had better beam focus.
I've been beginning to wonder if headlights maybe shouldn't be graded pass/fail, but perhaps weaken with age.
They do get worse with age. The lens itself degrades such that while it may be barely perceptible to the eye, it blocks a large portion of light, and alters the beam focus, as well as increasing glare for other drivers because light starts lighting up the lens rather than passing through it. (Picture driving into the sun with a dirty windshield vs. a very clean one. With the dirty windshield, more of it becomes unbearable to look at than with the really clean one wherein the sun itself is in sharper focus. Also, don't look directly at the sun!
) On top of the lens degradation, the reflector surface
also degrades. This combination of degraded reflector and degraded lens means your headlamps are seriously less effective after ten years than they were when new. At 15 years, they are all-but-done.
Since then, with other vehicles, I have replaced single bulbs without making any effort to find an "improved performance" replacement, and it has seemed as though the new bulb is brighter than the other one.
Another reason to replace bulbs in pairs. The obvious reason is that the other one in the pair is also not long for this world, but you also match the beam focus and lumen maintenance between lamps when done in pairs. It is interesting to see the difference, so I can see doing it out of curiousity, or doing just the one because it's raining and you're trying to get home, but doing them in pairs right away is the best method. The same for tail/stop/turn lamps-- those particularly keep burning long after they're useful, and turn the inside of the envelope into what looks like black pearl. I'd almost go as far as doing the sidemarker lamps the same way, especially if your front sidemarkers flash with your turn signals.
I typically pursue solutions in order of ascending cost. Headlight aiming being a zero cost solution it was among the first things I looked into. They were aimed a little high, which gave the low beams a little extra reach, but made the high beams useless as they hit more sky than road. This was corrected in the first month I owned the vehicle. This yielded some improvement, but not yet enough. Presently I'm using the fog lights to compensate for this deficiency, but I would like to end this as soon as I can. It irritates me to burn four bulbs where two should be getting the job done.
Fog lamps aren't auxiliary low beams; at speeds higher than fog lamps are useful, they just create more foreground light-- which also tricks you into thinking you're seeing better.
Are
these the same as the ones you suggested? One says 9008/H13. The other just says 9008. Once is cheaper than the other, is there any other difference?
9008 is a trade number (probably foisted upon us by Ford), not the official designation.