2008 A6/ 3.2 L

Since I have the bumper pulled to replace the radiator, perfect time to explore upgrading headlights.

As I understand it the basic headlight replacement would be an H7 bulb, is there an upgraded direct replacement/(LED, etc..) that anyone would recommend for enhanced lighting/visabliity?

It would be interesting to know if there is option to update the entire lighting assembly to the next generation or current style that have LED running lights, etc.... Could this option be installed without a complete rewire???

As always I appreciate your time and thoughts:-))

 

Does the 2008 A6 have an option for non-HID lights? I have never seen one that wasn't HID with a D2S bulb.
If yours are just halogen with H7, that is way easier to deal with - first question is what condition your lenses are in as this is the primary source of reduced light output, sanding them and re-coating with Spraymax 2-in-1 headlight clear or similar will solve that issue. Then, as long as your reflectors look good, I'm a big fan of the Osram Nightbreaker bulbs. LED retrofit bulbs are a meme, I haven't seen a single one that wasn't chinese trash (this is why most of them come with "lifetime warranty") and I am not aware of any DOT certified solution to put LED bulbs in halogen reflectors - you just can't put LED bulbs in a halogen reflector with good results. Sure, it "looks" brighter when you are close to the car casts more light around both sides of your view from the windshield, but if you compare the actual amount of light cast vs. distance on the road you are driving on (i.e. in front of the car), I don't see how any LED could ever win over a good halogen bulb in a halogen-designed reflector. Plus, that extra perceived "brightness" will just blind all the oncoming drivers until a competent cop pulls you over for "driving around with your brights on" and makes you put the correct bulbs back in the housing.

 

Appreciate the quick reply!

One of the lens is in bad shape. There are numerous solutions out there from baking soda/lemon juice to off the shelf kits. I believe your options is the best by sanding and reciting with clear coat. Could you please share the process...what grit(s) paper/assume wet sanding...then the clear coat, if I use a rattle can clear coat will that work or do I need specific Spraymax?

I believe mine are standard Halogen's....so will look for your recommendation: Nightbreaker bulbs

Forgot to inquire re: fog light bulbs......do I assume to follow and replace with Halogens too.......I ran across these Sylvania's as an option.

Thanks for your follow up!!!

 

Attachment didn't work, trying again re; Fog Lights/Sylvania LED's


Here are the flog light replacements I was considering

 

I did not realize a major brand like Sylvania was making H7 LED replacements now. They certainly would have gone through the DOT certification process and verified performance, that is very interesting.

In regards to the headlight refinishing - For these larger C6 lenses, my preference is a random orbital palm sander, not a drill. The smaller drill sanding pads are expensive anyway. I buy the assortment of 4(4.5?) inch sanding pads off of amazon. For really bad lenses, like crusty yellow from the bottom of a 30 year old ashtray yellow, I might start with 220 grit but usually I start with 400 grit. Break through the yellowing, you will see the color change quite quickly. If there is any original clear coat remaining on the lens, you will also see that, it actually stays "more clear" than the surrounding bare plastic until you get through it. Then I work my way up, 600/800/1000/1200/1500/2000, finishing with 2500 or 3000 (whatever I find is still available in the sandpaper drawer, I think 2500 might be sufficient for most older lenses). Then I finish with some polishing compound and one of those cheap foam polishing pads which also velcros to my palm sander (can also get them for drill, like what comes with the 3M headlight polishing kits). I usually make 2 polishing passes.

For all of this, I am wet sanding, but I don't dip the paper in water because the palm sander is, uhh, AC powered. What I do is sit on a short stool with a towel across my legs. Next to me is a clean bucket (no dirt around the edges) of clean water. I drape a washcloth over the edge of the bucket. I lay the headlight lengthwise sorta halfway between and halfway on my legs, on the towel, and at the beginning I wipe down the surface of the light (which should already be clean, no dirt) and also wipe the surface of the sandpaper or at least smack it with the cloth to get some water on it.
When I am sanding the lens I am making long passes forward and back, with my Bosch sander it seems to make good contact with about 2" of headlight surface (I don't press down very hard at all, more just gravity plus a little down force from my hand). Let's say "one pass" is enough trips down and up the headlight to cover the whole surface. So for every one pass, I pause, get the cloth wet, maybe squeeze it out a little if I don't want my legs soaked, and wipe the surface clean (which leaves some water). At the end, I might follow this process and do the final polishing, but then wipe it really clean, and then do the polishing again out of OCD.

After sanding and polishing, I clean with SEM 38353 plastic and leather prep. I am not sure if this is necessary. I just have it on the shelf, so I use it. Probably could just use pure (99.x%) iso alcohol. In fact maybe that's all that is in the can, lol.

Next, I use Spraymax 2K 2-in-1 clear. Make sure to download the PDF instructions, have to let it flash in between coats. I usually do 2 coats, recently I was near the end of the can and I wanted to use it up and I went with 3 rather thick coats... This seemed to result in some cloudiness, kind of hard to see but definitely not as clear as they normally come out. So just make sure you are coating in the right temperature range, and letting it flash long enough between coats.

Now, after your last coat, it isn't gonna look that great, it might look like it is covered in sparse rain mist, it might look foggy, no worries. Time to cure. For curing, you can use an oven with a temperature sensor in it (I use a thermocouple meter) but you won't be able to get the right temperature without propping the door open. If you close the door most ovens lowest settings will still be too hot, curing this stuff too fast is not necessarily good also you don't want to overheat your headlight housing. Also your wife might shoot you because of the smell. The alternative is an IR heat source like a reptile lamp, I just use two of the heat lamps that I also use for keeping baby chicks warm. You need something to check the surface temperature of the light while curing, I recommend a cheap-o laser IR thermometer, they are cheap on ebay and even the cheapest one should be fine. Check the temperature with the laser pointing at the black edge of the headlight housing right below the lens, you will get an incorrect reading on the surface of the lens because clear plastic is way less emissive than black plastic.

Once they are cured and cooled down, expect to see orange peel on the surface, this is pretty normal. Wet sand by hand with 3000-4000 grit sand paper, doesn't take much effort, fold the paper up, dip it in water and just start sanding like it's a piece of grainless wood. Usually takes a minute tops per lens. Shine a decent light on it and you will see the orange peel disappear. After that, just polish with the polishing compound once more. End result should be a light that is pretty close to OEM, minus any imperfections in the lens (big dings, crazing, etc will still show a little bit). Even really crazed lenses are still cleaned up a ton by this process, I've seen lenses that were crazed quite badly but after doing all of this the crazing was only visible if the headlights were on, at night, and you were looking closely.

Speaking of crazing... If you have any crazing in the lens, NEVER clean it with any aggressive solvent, not even the mildest brakleen that seems totally safe on plastic (don't ask me how I know), only use something like the SEM plastic prep or maybe iso alcohol. With a crazed lens, if you use anything which affects plastic *at all* the solvent wicks into the cracks of the crazed surface and permanently worsens it, no amount of sanding will fix this. It doesn't destroy the lens, but after using such a solvent just expect that every crazing crack will still be visible after sanding and coating.

I think that about covers it. For polishing compound, there are lots of options, 3M makes a plastic polishing compound in a bottle that I'm pretty sure is the same thing they include in their headlight restoration kits and that is what I use. I get the cheapest foam pads off Amazon so that I can just toss them in the trash after doing a few headlights.

 

Oh, and I misspoke, it's SprayMax 2K 2-in-1 *headlight* clear. I believe they add plastic adhesion promoter to the mix, this can is specifically for headlights.3684068 and in my experience you can do 4 headlights with one can (I've done as many as 6 with 2 coats) so if you have any other lights you want to do, get them all ready at the same time due to the pot life of the can. The can has an activator on the bottom, you have to use it within something like 8 hours, and make sure you shake the hell out of it. I have had really good luck with the spraymax stuff. Previously, I used SEM solaray, but that prpduct required a primer coat (for plastic adhesion) before the final coat and I'd say about 1 out of 10 lenses ended up screwed up and I couldn't figure out why, but it was definitely related to the primer coat because the affected lens looked different than the others immediately after the first final coat. That is actually how I discovered the solvent issue with headlight lenses - I noticed a headlight with "that look" and knew I was going to have to redo it, so I tried to remove the clear and primer before it cured... I wiped it with a rag soaked with this cleaning solvent that in my experience was "totally plastic safe". That was a mistake. Always let them cure first even if you think that you screwed it up. Remember you have a pot life on the can (I think 8 hours) and that is enough time to coat 2 lenses, realize you screwed them up, sand them down again and re-coat them with what's left in the can with plenty of time to spare.

 

I've done some headlight restorations in the past, and with the last one, a '10 A4 quattro avant, if I had thought about it, I would have just replaced the pair with aftermarket LED headlamps. Not sure what's available for the A6...

Even if you do restore the lens, you have an aging reflector still in place.

 

The reflectors in the chinese assemblies are just horrible. In most cases the ones I've bought had worse light output than an OEM housing with 10+ year old reflectors. I know they use a similar plasma vapor deposition process but they must be using a thinner coating for cost, or pot metal instead of aluminum. I don't know. Haven't seen a single chinesium assembly that impressed me in any way. If you restore OEM housings they are good for another 10-20 years so that's the route I go.