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96 Tahoe Transfercase

  1. Please fill out the following to ask a question.

    MAKE:Chevy
    MODEL:Tahoe
    YEAR:1996
    MILES:
    ENGINE:383
    DESCRIBE ISSUE....I picked up a 96 Tahoe 4X4 with no motor, trans, wiring and no engine control module. I installed a 383 motor, 4L65E trans, MSD EFI and TCM. The RPO codes for the rear end are, GU6 3.42 ratio and G80 posi. Tire size is, 245/75R 16, and I think the transfer case ratio is 2.72. My problem is I just got it running and my RPM was 4,000, going 40 mph, in 4th gear. Found out I was in 4wd low. Got it out of 4wd low,
    for testing I removed driveshaft to front differential and know I am at 3,000 - 3,500 rpm, 45 mph in 4th gear. I am thinking I might be in 4wd high? If so how can I get it into 2wd high? Most wiring to transfer case and trans was removed when I bought this truck. Thank you for your help.
     
  2. what i need from you is what transfer case you have and is it a manuel or electric shift transfer case
     
  3. Its a 243 C, Electric. Some times the 4hi and 4low lights on the selector switch will light up, but dont work. Most wiring in engine bay was removed.
    Thank you.
     
  4. ok what you can do is take the motor off the transfer case and turn the selector shaft with plyers toward the rear of vehicle untill the front shaft spins freely
     
  5. Thank you very much, I will give it a try.
     
  6. bp0, Thank you very much, it worked!!

    Thanks again!
     
  7. Of coarse it worked,;)

    Thing is, do you want to make it 4x4 again? If so, make sure you have the right transfer case electric motor selector. I ran into a similar problem with a few suburbans. one pcm to another was different. A few had fly by wire throttle, pcm was different. Would not recognize the transfer case MODULE for some reason. Module is located right next to the brake booster, Flashing lights and would default to 2wd drive. Some of those transfer case selectors have two connectors, others only one.

    I say this because those trucks came with different RPO's as you stated. But I am sure you already knew that, if not, you wouldn't have wrote that. ;)

    So when an engine would seize, or a tranny froze, had to modify. 2wd drive was not an ideal situation for the 54th parallel. But to get it driving when a front diff went out, just remove shaft, turn selector to rear position as BP stated.

    I was working for a fleet of northern trucks, I ended up welding a few bolt to selector shafts. That way, In a pinch, when 4x4 was needed, just reach under truck, 3/4 wrench in hand and voila, 4x4. Not ideal, but works when you need the 4x4. Yeah, my boss was that cheap. But hey, I guess that is how he became a millionaire. Trucks would go nuts, but who needs 4000rpm in a northern region like that. It was a sort of crazy far west story most ppl won't believe until you actually get up there and do the work. Boy oh boy, I had no idea what I signed up for. Sure was fun, pay check was awesome, but not a long term life thing for me. Great experience for a young buck though, who has no kids and such. My boy is 14 now, so he didn't miss me much, x box and all. ;) Still working on trying to get him to kiss his first GF. :eek:



    If you don't want to invest, just weld in a 3/4 bolt.

    :):bat:
     
  8. When I got up there, half the trucks had no front shafts, all in 2x4 mode. Learned the hard way how to modify a 8400under slash over truck to one another. Is it fun, hell no, is it worth it, heck no, but when you need to do it, no choice, your up north were the only way in is by plane or train. :giveup:
     
  9. I saw shyte up there you would never believe. Was it all legal? heck no. But who cares when you see the local police coming to the shop with their skidoo's strapped with a tree branch and such. Up there, no go means death. So improvisation is a much needed skill. ;)

    I once just went out for a walk, just to see some non existent wildlife. Got caught in a frenzy blizzard, lost my north. When wind died down, had no idea where the f I was. At some point, a innu tribe guy came by and saved my frozen white arse. He sure got drunk on my dime for sure when we got back to the village. They know those parts by heart. Crazy intuition those ppl. Very wise and very kind. Just don't piss them off. ;):beer: Once you have earned their respect, it is for life.
     
  10. nickb2, sounds like you have had some interesting experiences in your life. Thank you for the help, I think I might weld a bolt on to the shaft since I do not have the OEM PCM or controller for the transfer case. The MSD trans and FI controller will not control transfer case. What should I do about hooking up the electrical on the front differential? Thanks again for your help.
     
  11. First off, no electrical on the front diff. This is after all a Tahoe, right? Same shyte as a burb or 6 nut wheel.

    I think I will have to ponder on this and report back for a work around that will be to your liking.


    Yeah, life experience, it's a long way to the top if you want to rock and roll,\




     
  12. It's harder than it looks. ;)
     
  13. Nick, can you post a few details? I don't know spit about this, but I do know about electric motors. If the shift motor is still available, it shouldn't be too hard to operate it from manual switches.
     
  14. Thank you Nick. There are two connectors on the passenger side axle tube. I did hook up a SPDT switch to the motor and was able to go from 4w high and 4w low but into 2wd. Thanks again.
     
  15. I am assuming you meant NOT into 2wd. Well then, then that is a bit weird. So then let me rethink. A 383? Do you mean a 393 turbo diesel?

    If the encoder is going from 4w4 lo to high, the encoder in principle is ok. Something must be stuck in the front diff actuator or the circuit is bad.

    Which transfer case do you have in this truck, a borg warner or a new venture gear?

    I was wrong to say there was no front diff actuator. Disconnect the front diff actuator, if 4x4 disengages, you may have a short in that circuit.

    If the following chart applies to you, very easy to check that out. Screenshot (149).png
     
  16. Ok, wait a minute for me to catch up. A SPDT switch is a single pole double throw switch, correct? Maybe you are not probing the right circuit for 2wd selection? But in principle. you should be checking out the front diff actuator for disengagement of 4x4, correct?

    Once you tell me which of the four transfer cases available on these trucks you have, I will provide the proper wiring diagram. It will help me further to help you. Good on that?

    If you have a NV 241, it is a manual shift. If you have a 243, it is electrical shift. BTW you are writing, I am going to assume you have the NV 243, and here is that wiring.

    I uploaded that here, just click on the ACE 0 pdf.
     
  17. Both borg warner models are manual shift.
     
  18. Also which confirms what I think, if you have two connectors for the encoder, you have also a TCCM(transfer case control module.) That module is the one that sends the signal to the front axle actuator to disengage 4x4.

    I hope I didn't confuse you.

    Hope this helps.
     
  19. I picked up a 96 Tahoe 4X4 with no motor, trans, wiring and no engine control module or trans controller. I installed a 383 stroker motor SBC, a new 4L65E trans, MSD EFI fuel injection with compuer and MSD trans controller. Transfer case is a 243 C. I bypassed the encoder by installing SPDT switch at the connector where it plugs in at the electric motor.

    Thanks again for your help.