lrymal

Wow.... bringing up this old topic, but I never found an answer to the original question. Where is the cabin air intake? I changed out the cabin filter and found stems, whole leaves, lots of debris. I don't understand how those get inside the intake. There certainly are no openings that large by the wipe cowling where they could simply fall in. The only area that seems to collect large leaves is in front on the radiator area, at the bottom part of the grill. Lots of branches and large leaves trapped there. Does anyone have an old service manual with a diagram of the HVAC?

It is at Amazon, but really... there is no manufacture's link. The picture has ONEBIGOUTLET and a google search has that place as some clearing service. I listed the descriptor from Amazon which is about all I could find. How long have you been using your Morimoto 35w HID kit?

Howdy.... I have had my GMC Sierra SLT since 2014, and have been very fortunate in that the BCM voltage increase and German bulbs have worked very well. It has the signature LEDs which include the Daytime Running Light function. Works great. OK, am saying all this, which everyone knows. I just saw a headlamp replacement which "looks" great because it appears to split the lighting for the GMC into separate HI/Lo instead of our current single bulb with the shutter. I'm assuming that would mean the Lo beam could be adjusted to give a wider beam throw than what I have now. It has the ribbon LED which all vehicles now days seem to be going with. And the descriptor claims daytime running lights. That ribbon LED is really no biggie to me, I just want to have better adjustments for the illumination. I live in a very dark and hilly area. Sounds great?!? However, the descriptor claims this lamp assembly is not compatible with the GMC using the Daytime Running Light. And it is not compatible with the classic body style. So, am wondering if anyone has tried using it. 2014-2017 GMC SIERRA 1500 2015-2017 GMC SIERRA 2500HD 2015-2017 GMC SIERRA 3500HD *[Attention: Not Compatible w/ 2014 Classic Body Style ] *[Attention: Not Compatible For Model W/ Factory LED Day Time Running Light ] Image below.

Hmmmm.... Mine are right at a year old. So far, so good with a lot of night driving. Unusually lucky?

Be sure to take your truck out on a very dark farm-to-market road and adjust the aim. Do not rely upon the factory-speced adjustment. When you get the aim just right, it makes all the difference, even with the original factory bulbs. Do not expect much improvement for side illumination. That remains dangerously awful.

We have rolling hills in East Texas and the spot light effect of projector lamps is admittedly annoying. I aim on a flat road, though. I mean, that really is the only way you can have a reference. And I totally agree about the need for side illumination.

My Vosla bulbs were installed at the beginning of when this all began. I can't even remember, about January / February 2015? I am in a very rural area (no street lights) living on dirt roads. The bulbs have not failed, yellowed, or dimmed. For me, success for the illumination is proper aiming. We all know the projectors are lousy and maybe that is why the aiming is crucial, as maybe compared to other projector assemblies. Even BEFORE I had my computer flashed, re-aiming made a major difference. I used real-road aiming, drove around, touched it up, tweaked it, and got it right. With the many low-traffic farm market roads, I had no issues with road traffic. But, again, I have had no problems with the Vosla bulbs dimming, yellowing, or failing. Lots of hours on them since I work at night.

Vehicles are always improving, that's why. Also, I'm assuming that GM is telling the truth when the instruction sheet that came with the new bulbs and installation procedure is following the FED requirements to the T. I think the most the judge would do is to require a testing agency to certify the lighting follows the Fed requirements. I'll betcha that Fed standard is more ancient than I am. Changing the Fed requirements would be laughably difficult. It would take a modern day Ralph Nader (Unsafe at any Speed) to push the lawsuit into a Congressional hearing.

It'll be reviewed and dismissed once GM produces the Federal requirements for lighting which probably does not mention anything about the non-existant side lighting spill-over which is my main complaint. If the judge is interested, he'll want evidence that the lighting is not following the Fed's requirements.

It really is that bad for dark and hilly rural area. Not bad in town. The warm lamps, at least for me, are essential due to the fog and haze that we have. Bluish/white lamps tend to reflect their illumination into the eyes under such conditions.

The BCM update/reflash caused voltage to go from about 12 volts, to about 14, as measured. That made a significant difference even with the older 2012 bulbs. The bulbs in the bulletins are VOSLAs with a 28432 stock number and 12 volt @ 55 watt rating labeling. There are photos of this bulb with the labeling several messages back in this message thread. The 2 volt voltage increase, as measured, caused a significant brightness increase on the older bulbs, and brought up the illumination enough that even lateral illumination was helped. Go back about three months in the messages....

Look at most other cars which are using projectors, and there is an internal mirror-like reflector on the grill side of the headlamp wall. Ours is frosted. I think that is why we have the problem. Obviously, I'm speculating. But, look around and ya'll will see what I mean. In the meantime, check out these links: LEDs for corner lamps: http://www.smartlites.com/?i=4 http://www.stylintrucks.com/parts/kc_hilites_utility_led_universal_turn_signal_light/1104000048_KCHTU57073.aspx But, to make all of this automatic, you might want to add a delay module. Why? Feed voltage from the blinker circuit to the corner lamps above. Since the voltage is winking, you want a delay module so that the corner lamps remain lit. After about two seconds, after the direction lamp voltage stops, the delay modules kills the voltage going to the corner lamps. Delay module: http://www.alliedelec.com/amperite-12d-1-10sstb/70200200/ And no, I'm not in the mood to take on this project, but it should work. Just getting too old.

Would like to thank all the posters who wrote up the news about the illumination fix for the Sierras. We have had some terrible rains down here in Texas and I needed to go out this evening. Before the German bulbs, and the BCM flash, and the bulb adjustment, I would not have taken this $45,000 truck on the road, at night, in the rain. I live on a third-world rated East Texas hick road and this truck just couldn't handle it at night, or maybe I couldn't. I am grateful for y'alls help. Thanks again....

My bulbs showed up this morning, and I had them installed this afternoon. I also purchased two extra bulbs--I don't look for these to show up at Autozone anytime soon! The bulbs were adjusted close, but not to my liking for my rural roads. I spent about an hour on the road and finally got them absolutely correct. The difference is quite good, about how they should be when compared against older trucks. Reaches out and touches very well, lateral illumination is very good. Light spill over into dead zones, such as when going around a curve, is very good. I find the illumination to be average and it compares very well against my 2011 GMC. I no longer feel uneasy when driving this truck at night. No excuse for customers to go through all of this. Shameful--it was very dangerous.

Probably because this is a pre-recall, for the lack of the right words. We "enthusiasts" are ahead in the game and it'll be a while before the system catches up. Have them do the firmware upgrade, readjust the existing lamp aim, and things will be improved--you'll be able to see both shoulders with the factory bulbs. And when the German bulbs come in, it'll even be better.