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GMC 2500HD - Electrical system help

Discussion in 'Chevy Trucks' started by markq, Sep 26, 2005.

  1. markq

    markq Member
    Messages: 47

    Hello everyone. I'm looking for some advice on how to beef up my electrical system a little bit. :help:

    Here's a little background first.

    I have a 2004 GMC 2500HD Ext cab short bed. 8' Blizzard straight blade.

    I have a couple things that I would like to do, and need some suggestions.
    1 - I would like to go with a larger alternator. Will that mean that I need to change the bracket, or does someone make a larger one that will bold right up to the old location.
    2 - I also need some advice as to whether or not I should hook up dual batteries
    3 - I am going to be installing a 4 light hidden strobe system, and was wondering how difficult it is to get the lights hidden correctly. I am also trying to find a way to mount the switches for the lights. Ideally I would like to place them in the empty storage space above the rear view mirror, but I need to find something to mount them into so that it looks professional.

    I know, I know....lots of questions :confused: :help:

    Any help is appreciated!

  2. sonjaab

    sonjaab PlowSite.com Addict
    Messages: 1,425

    MARK.........If you have factory plow prep. you should have a
    140 or 145 amp. alt. Thats the biggest GM makes............

    If ya need more juice than that there are some alternator shops
    that will build up your existing unit for more output.

    Or you can spend some $$$ and buy a mega unit that pumps out
    some big numbers. Do a search and you will find other posts to
    these maxi units.................
  3. flykelley

    flykelley 2000 Club Member
    Messages: 2,124

    Try this" 05 chevy strobe install is done" It comes with pictures.

    Good Luck Mike
  4. flykelley

    flykelley 2000 Club Member
    Messages: 2,124

    Ok Markq
    when I tried to reply it wouldn't take my post, but it seems to be working now.
    1- Run your positive and neg wire all the way back to the battery.

    2- Do not drill a hole in the backup lamp part of your taillight, the strobe head will not fit. :yow!: Do not ask me how I know that.

    3- I can take some pictures of where to drill the holes for you, but I take no responsibility if they melt your taillight or headlight. I drilled the holes in my new truck in the same spot as my 01 chevy so it should be ok. The headlights are different on my 05 than my 01 so thats a crap shoot. I think they will be ok but only time will tell.

    Good Luck Mike
  5. Frozen001

    Frozen001 Senior Member
    from Rome NY
    Messages: 908


    You mentioned melting plastic... do the strobe ends(i.e. bulbs) get that hot??

    Just curious because I have been considering putting stobes in my truck

  6. markq

    markq Member
    Messages: 47

    You said that it wont fit in the backup lights, so where do I install it? I believe that all of the other lights on the back are red, which I know I cant do.

    Thanks for the inut though...this is exactly the kind of thing I'm trying to avoid.....drilling holes, then stuff not working :eek:

    I dont have the plow prep package, and I dont know what the stock alternator is rated at, but I run the plow, GPS, phone, radio, lights, etc.....I dont want to have any issues with a dead battery. Do you know if the larger alternators fit on the stock brackets?

    Anyone have any input on switches, and mounting them above the console?
  7. flykelley

    flykelley 2000 Club Member
    Messages: 2,124

    Yes Lou they need 1 inch clearance away from anything that will melt. You should not have any issues with the tail lights but I have not done this style headlight before so only time will tell if it will be a problem. I do have over 1 inch clearance in the headlight also so it should be ok. If not I will be glad that I get a GM discount on parts.

    Regards Mike
  8. flykelley

    flykelley 2000 Club Member
    Messages: 2,124

    Markq, look up that thread that I talked about in a early post. It has pictures of a switch panel that I made for the upper console. The strobe heads have to be install in the brake and turn signal part of the tail light. There is no other place to install them.
    Most cops will not bother you with them in there, just don't run the roads with them on. I only use them in the parking lots and when doing the approach to a lot. I have forgotten to turn them off and had no problems with the cops. That is why I am now using a lighted switch.

    Good Luck Mike
  9. flykelley

    flykelley 2000 Club Member
    Messages: 2,124

    I will be in the GM truck assy in Pontiac Mi on Wednesday night. I will go down to heavy repair and talk to the repairman that I know down there. Will post sometime Thursday am.

    Regards Mike
  10. PremierLand

    PremierLand PlowSite.com Addict
    from detroit
    Messages: 1,572

    not to hijack the thread...

    I have a 01 with plow prep. Does my truck have the larger alt? when I bought my belts on sunday (was going to put them on but the rain stoped me), he asked which alt I had, I figured it was the larger one due to plow prep. So ya, is it the bigger alt?

  11. ratlover

    ratlover PlowSite.com Addict
    from IL
    Messages: 1,325

    There is a way to pretty easily add dual alternators to you truck using all GM parts. Also the 145 amp alt is available but you have it if you have the plow prep. Dual batts are nice and you can do that with all gm stuff. I dont know all the info offhand but I know were to get it although I will get in trouble if I tell you :rolleyes:

    check out socaldiesel.com He has aluminum cover deals that go into the cubby hole for switches. He may only have the one with gauge holes listed but I am pretty sure he sells ones with how ever many switch cut outs you want.

    Also there is a plastic peice that is a GM part that fits up there and you can cut out your own switch holes. try gmdieseltech.com for that. he sells gm parts so you can get the dual alts through him too if you want em.
    Last edited: Sep 27, 2005
  12. sonjaab

    sonjaab PlowSite.com Addict
    Messages: 1,425

    MARK............YES !...............If you have the VYU plow prep.
    (look for code on list in glove box) you will have the 140 amp unit.......geo :drinkup: