How to LS Swap a GMT400 (or any other vehicle)

Discussion in 'LSX + Carb Swaps' started by Mike, Jul 30, 2013.

  1. 95chev

    95chev Fear the Deere

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    sub'd for reference
     
  2. Coveman

    Coveman OBS Enthusiast

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    Wow! Nice build
     
  3. 95SUBURBANLM7

    95SUBURBANLM7 OBS Enthusiast

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    OP, did I miss something or was splicing the OBS harness to the LS harness skipped? I'm doing a LM7 swap into a Suburban that already had a NV4500 swapped in place of the 4L60E. So now I'm at the point where I need to integrate parts of the LS harness into the Suburbans stock harness. I believe VSS needs to be spliced into the Suburbans C100 E6&7, but I'm not sure.

    I've searched high and low during the last seven months of this project and have found some great projects (Jeebalow, Green95Hoe, amongst many others) and some great written info (S&P's 13pg PDF), hell not to mention Brendan's amazing write up on lt1swap.com. With all of that great info, wiring the two harnesses has been glossed over for whatever reason(s). But that's ok, I guess with whoevers help I will fill in the blanks.

    Any help?

    Nick

    Edit: Nevermind, I found the info and I am compiling it here: http://www.gmt400.com/forum/showthread.php?32099-GMT400-to-LS-Harness-Questions
     
    Last edited: Oct 27, 2015
  4. 95Z71Mike

    95Z71Mike I'm Awesome

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    I have a complete 99 donor truck to do my LS swap in my 95 Silverado.

    What extra stuff am I going to need to buy?

    I would like to swap in the 99 gauges also. Would this easier then making my 95 gauges work?

    Is it like I'm thinking in my head? Pull the 99 engine and trans out with the harness and ecm and put it into my 95, wire up the power and ground and it all works lol

    I know gas lines and pump need changed too.
     
  5. thz71

    thz71 Stock SUCKS!

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    It'd be much easier to make the stock 95 guages work.
     
  6. MYT HI

    MYT HI LOUD AND PROUD

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    If he wanted he could maybe swap everything so it's not some 95 and some newer. Swap the dash and everything


    Sent from my 5.3 powered iPhone
     
  7. 95Z71Mike

    95Z71Mike I'm Awesome

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    I like the idea of the 99 gauge cluster, and if it's all connected to the ECU anyway shouldn't it work? I know theres some things I'll have to change though.

    I don't want to swap the whole dash and everything just the cluster. I seen somebody on YouTube did it and I want to find out how.
     
  8. thz71

    thz71 Stock SUCKS!

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    He would have to swap dash door panels a pillar covers at the very least. That's alot of work
     
  9. 95Z71Mike

    95Z71Mike I'm Awesome

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    Talked to a harness builder last night and from what I got out of it was...

    The VATS needs turned off to do anything...

    If I want to have the 99 gauges I'd have to use the dash harness from the 99 as well. And probably rewire the HVAC

    And I don't HAVE to rework the stock 99 harness if I don't care to have the extra wiring in the bay.

    Hope it works out for me...
     
  10. tommypvt

    tommypvt Newbie

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    I am going through this now with my 99 tahoe. I will try to get a writeup done on integrating the 99 underhood fusebox and hvac wiring done. It shouldnt be that hard once i get the wires sorted. Most of the guages come through the passenger firewall connector
     
    95Z71Mike likes this.

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