14-15 Sierra Poor Headlight Bulletin

15GMCSLT · November 3, 2016

Does anyone have the bulletin about upgrading the bulbs and upping the voltage to the lights?

It's Service Bulletin PIT# 5374A

Document ID# 4109395

I'm wanting to get this done but my dealer says the don't know anything about it. I want to bring a copy of the bulletin to them.

Anyone had this done to theirs?

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15GMCSLT · November 3, 2016

Looking for a PDF copy not just a photo if possible.

This is the updated version!

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tuckersnator · November 3, 2016

Had it done a few weeks back. No noticeable difference. Maybe they BS'd me too. Who knows. At this point I am looking at just doing a HID upgrade.

TJay74 · November 4, 2016

Had it done a few weeks back. No noticeable difference. Maybe they BS'd me too. Who knows. At this point I am looking at just doing a HID upgrade.

the upgrade if done correctly should have been a noticeable increase in output, it was something like a 45% increase in lighting from the BCM flash that upped the voltage and the brighter and whiter VOLSA bulbs. I would make sure your dealer put the correct bulb in, some only did the BCM update.

jhplak325 · November 4, 2016

Does anyone have the bulletin about upgrading the bulbs and upping the voltage to the lights?

It's Service Bulletin PIT# 5374A

Document ID# 4109395

I'm wanting to get this done but my dealer says the don't know anything about it. I want to bring a copy of the bulletin to them.

Anyone had this done to theirs?

Sent from my iPhone using Tapatalk

Depending on when your truck was built, it might already have the update done at the factory.

2016 Sierra Owner · November 5, 2016

I had this done to my August 13 build 14. It did seem to help some. All I gave my dealer is the PIT number and they ordered the parts. Some dealers are more knowledgeable than others I guess?

Haus_Z71 · November 6, 2016

the upgrade if done correctly should have been a noticeable increase in output, it was something like a 45% increase in lighting from the BCM flash that upped the voltage and the brighter and whiter VOLSA bulbs. I would make sure your dealer put the correct bulb in, some only did the BCM update.

It was barely noticeable for me. It took it from poor lighting (1 out of 5) to below average (2 out of 5). It may technically have better specs, but it's far from enough to consider it worth while or a solution.

I eventually just went with the Morimoto Elite 35w HID kit. $170 and well worth it. It now has the lighting you'd expect these trucks to have when you spend $36k on a new vehicle.

Also attached a picture of the PIT 5374A vs the Morimoto HID:

Haus_Z71 · November 6, 2016

Does anyone have the bulletin about upgrading the bulbs and upping the voltage to the lights?

It's Service Bulletin PIT# 5374A

Document ID# 4109395

I'm wanting to get this done but my dealer says the don't know anything about it. I want to bring a copy of the bulletin to them.

Anyone had this done to theirs?

Sent from my iPhone using Tapatalk

PIT5374A

http://www-odi.nhtsa.dot.gov/acms/cs/jaxrs/download/doc/UCM507797/SB-10057993-6793.pdf

PIT5374B

http://www-odi.nhtsa.dot.gov/acms/cs/jaxrs/download/doc/UCM507796/SB-10057993-1044.pdf

There you go. I didn't want to say "it's not worth it don't waste your time" without at least giving you what you needed.

But, I will say, it doesn't make a big difference. If you want effective lighting, you will need to install an HID kit. Very very easy to do. And affordable.

Imcrazy · November 7, 2016

When I had my Sierra, I had it done, it helped but, it was still very poor... Like others said you need a good HID kit, my 16 silverado has factory HIDS, what a difference.

TJay74 · November 7, 2016

Exceot for the fact the the Sierra SLT headlights are not designed for HID bulbs, but that is another argument. I would go with the new LED headlights before I went with the hack job that HID's require now.

truckguy82 · November 7, 2016

I had the dealer upgrade done, made a big difference.

Headlight performance is now on par with most new vehicles.

Anybody who says otherwise either did not have the job done correctly by the dealer, or is delusional about their expectations.

Before upgrade - brightness 4/10, after upgrade 7/10

vehicles I've driven since while paying attention to headlight performance

Halogen '15 rdx 6/10

Led '17 rdx 7/10

Led '17 mdx 8/10

'16 cadilac CTS led 9/10

'16 mercedes s-class 10/10

mdx, cts, and s-class all looked significantly more awesome with their knife edge night/day beam pattern, but my rating is more for brightness and practical performance.

My post dealer upgraded sierra has a highbeam performance of a 5/10 if I had to stick a number on it. If I lived in a rural area I would probably seek aftermarket options because of the high beams.

truckguy82 · November 7, 2016

Exceot for the fact the the Sierra SLT headlights are not designed for HID bulbs, but that is another argument. I would go with the new LED headlights before I went with the hack job that HID's require now.

I think everybody else would prefer the factory LED headlights too, but they cost A LOT more than a "hack job" hid upgrade.

WLC · November 7, 2016

I must be delusional times two. The upgrade was close to the trimmed 9011's. Volsa bulbs did not last long (dimmed) and many say they burn't out quickly. I think the original headlights look good but not much better than a good flashlight.Have LEDs now with aux lights. Basically a bad design by GM.

truckguy82 · November 8, 2016

I must be delusional times two. The upgrade was close to the trimmed 9011's. Volsa bulbs did not last long (dimmed) and many say they burn't out quickly. I think the original headlights look good but not much better than a good flashlight.Have LEDs now with aux lights. Basically a bad design by GM.

Or they were improperly upgraded and you're not delusional. I noticed a large difference. I cannot imagine how anyone could find the upgraded low beams to be inadequate. It leads me to believe that many dealers are not doing the upgrade properly.

It took the guy 2 hours to complete mine and I thought i saw somewhere it's an hour long job. Maybe they are skipping the voltage increase on some?

I've only had mine in since july so I can't comment on longevity.

Haus_Z71 · November 8, 2016

Exceot for the fact the the Sierra SLT headlights are not designed for HID bulbs, but that is another argument. I would go with the new LED headlights before I went with the hack job that HID's require now.

I agree they were designed for halogen not HID bulbs, but the cutoffs in these projectors are extremely effective and they accommodate an HID set up very well. I wouldn't say the HID was a hack job. It was very easy to install. The only thing that isn't plug and play is the caps on back of the housing. You need to make a small hole to add the new wiring.

I would think LED would be the way to go, but after reading several pages of comments in the lighting thread, it was a general consensus that aftermarket LED was not as effective as HID lighting.