4L60E / 4L65E & NP208 questions

Discussion in 'The Engine Bay' started by metalneverdies, Apr 12, 2016.

  1. metalneverdies

    metalneverdies 1/2 ton status Premium Member

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    Can you guys send a little info / advice my way?

    I did my swap keeping my 700r4 and np208 because at the time the adaptor kits were way spendy and my trans was supposed to be semi freshly rebuilt.

    Well, turns out my trans pump is bad / dying off. So now I am at a cross roads. Switch over to a 4L60 / 4L65 or get a fresh built up 700r4 made to handle 4x4 and 450 hp.

    I am leaning towards going to the 4L60 if I can get all the conversion stuff figured out and keep it on a reasonable budget.

    I read about and was checking out the advanced adaptors 50-0405e. If I use a 4wd 4L60 and the adaptor mentioned will it all bolt straight up to my NP208? The 2wd needs the shaft shortened, correct?

    Do I even need to mess with the VSS ring if I plan to keep using the VSS adaptor from Dakota Digitial that I am currently am running and cable speedo on my NP208? I didnt want to use the sensor off the trans shaft because I have heard all the issues with 4Lo freaking out the PCM and shift points.

    EDIT: I think I found what I need actually... looks like GM # 15005474 might be the ticket? Any one confirm this?

    Will that still work with the VSS I am currently using and have no 4LO shifting issues?
     
    Last edited: Apr 12, 2016
  2. metalneverdies

    metalneverdies 1/2 ton status Premium Member

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    After tons of google and a quick phone call, I have some info. Due to what advanced adaptors said I am a little iffy.

    Their adaptor p/n: 50-0405E and the original NP208 to 700r4 adaptor needs to be used. This leaves us with the same length trans assy as factory. And gives us a correct VSS signal.

    I asked about 97+ 4wd factory adaptors and they bolt straight to the NP208. This will leave the trans assy about 1.5" shorter. If I didnt already have my CV drive shaft built and custom front shaft that would be tempting.

    He kept saying the trans wouldnt shift properly with my dakota digital vss adaptor that runs off the cable on the np208. Is this correct?
     
  3. skunked

    skunked in the garage Premium Member GMOTM Winner

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    if you have 450 hp why mess around with the 4l60?
     
  4. metalneverdies

    metalneverdies 1/2 ton status Premium Member

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    I don't but I figure it's only like $200 more and you'll never have a problem with the transmission again
     
  5. skunked

    skunked in the garage Premium Member GMOTM Winner

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    I don't see the advantage of that swap. Again I don't know what your rig is but your comparing two transmissions are VERY similar so why go through the hassle?
     
  6. metalneverdies

    metalneverdies 1/2 ton status Premium Member

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    The idea for the swap is just that if I am going to sink nearly 2K into a rebuild 700r4 with a shift kit, why not upgrade to the 4L60e and have electeonic control over all my shift timing and settings. I would just need to add back in the trans wiring harness on my setup and it would be good to go.

    Ditch the silly 700r4 TV cable and have more adjustment over my shifts. Nice soft shifts when crusing and quick firm shifts when WOT. Plus then I can play around with my torque management enstead of having it fully disabled like I have to for the 700r4; which will help with trams life.

    Edit: as for rig setup.

    1987 K5, 5.3L/700r4/NP208. 3:73 10 bolt axles, auburn diff. Ord springs, shackle flip, bilsteins. Crossover high steer.

    Basically a fun cruiser / DD, sand toy, and light trail truck.
     
  7. MAX89K5

    MAX89K5 1/2 ton status Premium Member

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    He is right, an inline VSS will not provide a precise enough signal to run a 60e properly. You need to find a way to incorporate a factory type VSS. If you have to put the sensor in the tcase output, all you have to do is run one wire to a switch that will be activated when the tcase is in low range. I put a switch on the shifter gate that was pressed by the shifter whenever it was pulled back. The computer will then automatically adjust shift points etc.
     

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