+ Reply to Thread
Page 1 of 2 1 2 LastLast
Results 1 to 10 of 18

Thread: 4.3 to 5.3 swap

  1. #1

    4.3 to 5.3 swap

    hi everyone i blew the 4.3 in my 05 last nite so i have decided to try and do a swap. i have the motor found but my main concern is my truck is 5spd and the donor truck is an automatic, will the wiring harness be different ?

  2. #2
    Join Date
    Nov 2003
    Location
    Denton Texas
    Posts
    20,540
    not too much different. Put the auto trans in there too. You'll be glad you did. You'll need remove the clutch pedal and install a shifter but thats easy to do.
    Last edited by RedHeartbeat; 06-10-2008 at 09:48 AM.
    See my truck data in the "My Garage" section here... http://www.ls1truck.com/forums/my-ga...tml#post191709

  3. #3
    no im not gettin rid of the 5spd. id rebuild the 4.3 before i did that.

  4. #4
    Join Date
    Nov 2003
    Location
    Denton Texas
    Posts
    20,540
    Time to go flywheel and clutch shopping. If I remember correctly the 4.3L 5 speed flywheel won't work since its bolted to a crankshaft built on the Gen1 engine dimensions.
    See my truck data in the "My Garage" section here... http://www.ls1truck.com/forums/my-ga...tml#post191709

  5. #5
    i figured id have to get that stuff from a 4.8 what im worried about is the wiring?

  6. #6
    Join Date
    Nov 2003
    Location
    Denton Texas
    Posts
    20,540
    I can't recall any transmission hookups on a 5 speed going to the PCM other than a clutch pedal position switch.
    See my truck data in the "My Garage" section here... http://www.ls1truck.com/forums/my-ga...tml#post191709

  7. #7
    ok man i really appreciate the info. could this swap be done in a week? im takin the week off from work and i need it fixed by next monday because i use it for work.

  8. #8
    Join Date
    Nov 2003
    Location
    Denton Texas
    Posts
    20,540
    Have you ordered a tuned PCM for the new engine? Do you have HPTuner or a programming software to remove the VATS security software? I'd budget two weeks worth of time to do it in since you've not done the conversion before. Be sure you read the conversion posts on here a few times. Ducky did the conversion recently and did a nice job of documenting his obstacles he encountered.
    See my truck data in the "My Garage" section here... http://www.ls1truck.com/forums/my-ga...tml#post191709

  9. #9
    Join Date
    Nov 2003
    Location
    Denton Texas
    Posts
    20,540
    Also, be sure to read the topics related to putting a 5 speed behind a genIII engine.
    See my truck data in the "My Garage" section here... http://www.ls1truck.com/forums/my-ga...tml#post191709

  10. #10
    i have a tuned pcm now with free updates for life. ill be sending it out tommorow i think. im just afraid im gonna get this started and not be able to get the wiring straight.

+ Reply to 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