Headlight question

[davidra]

I know absolutely nothing about headlights; recently purchased a used Denali; great car, but the headlights suck. All kinds of defects from the weird lamp arrangement, and very yellow. What do I need to do to switch to halogen? Or if I can't, a better bulb?

[iddibhai]

two things: see if they are aimed properly first of all. if under warranty, ask the dealer to look at it. then as far as headlamps go, you can drop in Sylvania XtraVision (pink and black packing, found nearly every place that has any auto parts).

http://www.danielsternlighting.com/tech/aim/aim.html

[davidra]

Thanks!

[Vortex]

Very yellow can mean two things, either the bulbs are really old or there is a significant voltage drop in your vehicles wiring. Here is what I would do, first go get some premium bulbs for your Denali. Install the new bulbs and check your owners manual and make sure the light are properly adjusted.
A cheap way to tell if your lights are miss aligned is to drive up to a wall or a building at night and check to make sure the brightest parts (hot spots) of your beams are level with one another and make sure that they converge at some where around 75 feet or so in front of the vehicle. It varies from vehicle to vehicle. See you owners manual and if there is nothing there check just use these guidlines "The U.S. vertical aiming standard is 2.1" of drop at 25ft, or 8.4" per 100ft" taken from here: http://faqlight.carpassion.info/hl-aiming.htm

If this does not help and your lights still seem yellowy, check the alternator to see if it is giving you a bit higer than 12V, for exmple my vehicle operates at around 13 to 13.8 V. If your alternator and Battery is healthy and the lamps still appear yellowy then there is probably a significant voltage drop in factory headlamp wiring. Even a drop in .5 to 1V will make a huge difference. If so You will have to add an aftermarket better performing Headlamp wiring harness upgrade. Find out what type of lamps your denali uses and go here: www.suvlights.com (the site is being revamped so it's down temporarily) They sell plug and play wiring harnesses that take the juice directly from your battery to your lights by using nice 12 ga, wiring a nice heavy duty relays. You can use this harness with higher wattage bulbs if you desire even more brightness [img]/ubbthreads/images/graemlins/wink.gif[/img] And if your Car uses 9005/9006 bulbs then you are in for a bonus because there is a little trick you can do with the 9005 to make it fit into a 9006 socket by simply filling down some plastic tabs. Doing this will give you at least a 70% increase in light. An average 9006 bulb puts out +/- 900 lumens at 51W where a 9005 does a whopping 1500-1600 lumens at 60W.

Good luck with your lighting needs [img]/ubbthreads/images/graemlins/smile.gif[/img]