GM Truck Club
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER
Page 2 of 2 FirstFirst 12
Results 11 to 16 of 16
  1. #11


    The capacitor is just a temporary fix. It's just more work that the alternator has to do. Your electrical system shouldn't be flickering with 400watts. I had 600 watts on my stock system and the only time it flickered was if I hadnt started the vehicle in awhile or if I used the windows. Once I got a optima yellow top I went to about 1,000 watts and I still didn't have flickering. Every GM truck I've been in has flickered when the windows are being rolled down or up. I would sell the capacitor and get a better battery from like optima or something similar. I would also do the BIG 3. That will probably help the most.
    Bagged 06 Silverado Crew Cab.

  2. #12


    consider buying a deep cell battery or upgrading your alternator. a deep cell battery from optima runs about 200 bucks. a oem high output alternator for your truck is about $140 or more depending on how many amps you want. i upgraded my alternator to the drg44 alternator from a silverado ss and got a 2 farad capacitor and upgraded the wire from my alternator to my battery to a 4 gauge wire. my lights never flickered again. im running 2 power hx2's and a 1500w jbl amp.

  3. #13


    I fixed my flickering by making sure that everything was grounded ( cab, engine). To the frame.

  4. #14


    Wow. If I understand correctly, this person has a 400 watt amplifier. No information given about any additional amplifiers.

    A stock alternator on that year truck can drive up to 1500 watts no problem, and you absolutely do NOT need to change the "big three" wires to 0awg. That type of overkill should be left to those with OCD. If you have four gauge battery wire at positive and negative, that is plenty large. 2 gauge if you want.

    A capacitor does not over tax the alternator or the battery. It stores energy and discharges only when the load requires it by taking more voltage than the battery can deliver to the load. If your lights are dimming, it is illogical to conclude the diameter of your power source wire is too small. I am running three 500 watt Soundstream Reference AB amplifiers in my Infiniti with no extra stuff and no upgraded wiring and everything works to full volume to the point that it will destroy all my components and the sub woofer if the volume is turned up too loud. No dimming lights, ever.

    The one place I agree you should upgrade wire diameter is between the alternator and the positive battery post. Four gauge should work.

    In my truck I run two four channel amplifiers totaling around 1000 watts, and I have 2 gauge power wire and a 175 amp alternator with the OEM wire running to the battery from it. I am going to replace one amplifier with two two channel amps, one will be 500 watts, the other will be 940 watts, and I might put a capacitor between the large amp and the power block, but that is it. I use an Optima yellow top deep cycle battery. My lights in my truck have never dimmed even when all the original power wire and the OEM alternator (100 amps) were in the truck with one 600 watt 5 channel amp.

    I suggest you start simple and test the battery. It could be you just have a bad battery or a bad ground. Grounds are probably the most overlooked source of electrical issues in cars by do-it-yourselfers. I installed, at the recommendation of my technician at the shop that does my engine work, a 4 gauge ground wire from the battery negative to the rear frame parallel to where I have my ground posts (in the floor) for the amplifiers. I run another 4 gauge wire from that point to one of the ground posts on the floor. I use copper terminals and copper washers and clean the areas with sandpaper followed by DeOxIt electrical contact cleaner, then put the posts in place with the ring terminals.

    As one person posted above, the alternator is not keeping up with electrical demands, and it is possible the alternator has a problem, but start with the battery. Often that is the only problem. If you want the alternator tested, I recommend taking the truck to an auto electric repair shop and have them test it, and tell them what you have for aftermarket electrical loads.
    Last edited by The Heater; 10-09-2012 at 01:49 AM.
    1994 Chevy K2500 Silverado, 454 (modified), original owner.
    And other vehicles and toys.

    "...If you can meet with triumph and disaster
    And treat those two imposters just the same;'ll be a Man, my son!" Rudyard Kipling

  5. #15


    When my alternator went out I replaced it with a new one (still the stock 105amp) like the factory one. I had headlight flicker when I ran my window up and down buttons on the doors. I also put a new battery in it and then a month later went to dual yellow tops and that made a difference.

    Then @SurrealOne helped me with a 1/0 big three upgrade and there is no flickering at all. I still am looking at potentially moving to a 250-350amp alternator at some point. I plan on adding allot of after market electronic stuff in the future.

    When I am at the point that a new or a new to me used truck presents itself, the first 3 upgrades will be the big three, alternator and dual batteries before anything else is done.

  6. #16

    Enkeiavalanche's Avatar
    Join Date
    Apr 2010
    Piermont,NY, back in Northern NJ now, But may be in IL soon....


    If your lights are Dimming add the Cap to them.. Do a Good Alt like a Ohio Gen and good Battery and the big 3 But as said above 4Ga will be fine...Old Avalanche 950 Watts RMS Never a Light dimming issue in 6 Years....
    08 Z71 Avalanche Mods to date: K&N CAI,Hellwig Swaybars and End Links, Corsa Sport Exhaust, Superchips Programer,IPCW LOF & 3rd brake light and tails, AMI Gas door,Show Hooks and Door locks, Enkei Wheels, with Pirelli tires, StreetScene Bowties, Grant Steering wheel,Muth signal mirrors,SSBC Big Brake kit,Huskyliner Mug gards,Floor mats and Hood shield, McGard Lug nuts and locks, Bedrug, Cervini's Ram Air hood,35watt HID Fog lights, Sylvania bulbs all around ZXE's Highs and Lows, WhiteNight Back up lights,Sirius and HD Radio, SnugTop sitting on deck now Got a Softopper on now,Tempress Boat Hatches.... New Bilstein shocks are on... New Mods coming soon..... X

Page 2 of 2 FirstFirst 12

Similar Threads

  1. 94 GMC suburban,rear running lights/dash lights fuse?
    By Rancor2001 in forum General Chevy & GM Tech Questions
    Replies: 4
    Last: 12-21-2009, 07:24 PM
  2. HIDs flickering?
    By redneckarmyMP in forum Lighting Discussion
    Replies: 8
    Last: 09-02-2009, 09:29 AM
  3. 1994 silverado no instrument lights dash lights
    By woodslip in forum Audio, Video & Gadget Tech
    Replies: 3
    Last: 07-12-2009, 11:47 PM
  4. dash lights
    By 2wheelin in forum GM Electrical Tech
    Replies: 3
    Last: 12-13-2007, 04:33 PM
  5. Lost dash lights and tail lights???? [Expired Topic]
    By martone68 in forum Chevy Suburban Forum (GMC Yukon XL)
    Replies: 4
    Last: 03-12-2006, 07:02 AM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts