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DOUG NASH ENTERPRISES OVERDRIVE - DNE2 - US GEAR - DUAL RANGE revival

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  • DOUG NASH ENTERPRISES OVERDRIVE - DNE2 - US GEAR - DUAL RANGE revival

    Since there is a distinct lack of information out there on the Doug Nash Enterprises Dual Range, or DNE2, I'm going to try to put everything I have gleaned on them in one place.

    And document reviving this one that I got from SuperBuickGuy "recently" .


    These 2 terminals connect to the reversible 12v motor by means of a neat limiting switch.

    Ground is through the case and one terminal is 12v positive for high range and the other is 12v positive for low range. After last nights diagnosis session I'm not positive which is which, but I will figure that out later and post the info.

    I was unable to get any sign of life by hooking my jumper pack directly to the terminals, so the cover came off. I then bypassed the switch, same thing, nada.





    So I pulled the motor. You can see it here as the thing on the upper right with the triangle-ish 3-bolt cover. Slides right out after removing the limiting switch, just mind the wires so they don't get caught on the way out.



    This is just a picture of the other end, which bolts onto the transmission (a TH400 in this case) in place of the tailshaft housing.




    In my case, all of the electrical connections were covered with a semi-hard black coating. I suspect this is a deposit from the gear oil that splash-lubricates the engagement mechanism?

    In any case, some time spent cleaning terminals with a bit of fine sandpaper and the motor roared to life. Both directions even. I'm betting it has been quite a while since it has been actuated as it took several seconds to reach full RPM, but after that it performed perfectly.

    Bolted it back together and tried the external terminals, nothing. Rats.....pull it back apart and start cleaning the limit switch.

    The sandpaper is being used on the pivots to try to get good contact in that area. You can see how the switch slides back and forth? The contact areas there are relatively easy to clean, but following the electrical pathway shows that the pivots likely are gunked up as well. They have tiny wavy washers in them to keep things snug, so I snuck the sandpaper in there and did my best.

    Compare the semi-clean left pivot to the still dirty right one. The contact areas are both cleaned in this picture, but note the area in the notch of the slide (activated by a pin on the sector gear). That lumpy looking blackness is the deposit, I can't get in there and it is not really necessary to clean it at this point.

    In this picture the left contact is closed and the right one is open. When the pin on the gear moves all the way to the left, it will cause the left contact to open and will close the right contact. Neat how it stops the motor from overrunning and also readies the circuit for the next shift.







    Apparently cleaning switches is Dog-Speak for "I want to play with the squeaky"? I settled for cleaning the switch, reassembly can wait until after fetch wears the dog out.




    One of the motor retention screws was badly bent, so I'm picking up a replacement today. I'm fairly certain the switch is fine now, will reassemble and test tonight.
    Last edited by STINEY; February 26th, 2014, 09:45 AM.
    Of all the paths you take in life - make sure a few of them are dirt.

  • #2

    Re: DOUG NASH ENTERPRISES OVERDRIVE - DNE2 - US GEAR - DUAL RANGE revival

    can you by pass that mess and use a basic stepper motor

    Comment


    • STINEY
      STINEY commented
      Editing a comment
      Not really wanting to reinvent the wheel......if things were unobtainium I would just fab up a mechanical linkage to do the same thing. Something using a Morse cable would work nicely I think.

  • #3

    Re: DOUG NASH ENTERPRISES OVERDRIVE - DNE2 - US GEAR - DUAL RANGE revival

    Interesting.
    Escaped on a technicality.

    Comment


    • #4

      Re: DOUG NASH ENTERPRISES OVERDRIVE - DNE2 - US GEAR - DUAL RANGE revival

      I recognize that piece of scrap.... errr.... fine piece of automotive engineering
      Doing it all wrong since 1966

      Comment


      • #5

        Re: DOUG NASH ENTERPRISES OVERDRIVE - DNE2 - US GEAR - DUAL RANGE revival

        Don't forget the post the manual




























        Comment


        • #6

          Re: DOUG NASH ENTERPRISES OVERDRIVE - DNE2 - US GEAR - DUAL RANGE revival

          Ooohh!
          Escaped on a technicality.

          Comment


          • #7

            Re: DOUG NASH ENTERPRISES OVERDRIVE - DNE2 - US GEAR - DUAL RANGE revival

            so what are the gear ratios in that box? Vehiclvehicle did it come out of or is an aftermarket item?
            http://www.bangshift.com/forum/forum...-consolidation

            Comment


            • #8

              Re: DOUG NASH ENTERPRISES OVERDRIVE - DNE2 - US GEAR - DUAL RANGE revival

              is this for the boat? I did a major WTF!? the first time I heard a boat shift. One of my sicker recent ideas was a 4+3 Vette with a Cummins 3.3, after researching the 4+3 that idea went away. They used what was basically an automatic behind the manual. Good to see gears in here!

              did dog gnaw your arm off ?

              Oh yeah, Tardis, awesome find on the parts / installation guide!
              Last edited by Beagle; February 27th, 2014, 05:29 AM.
              Flying south, with a flock of bird dogs.

              Comment


              • #9

                Re: DOUG NASH ENTERPRISES OVERDRIVE - DNE2 - US GEAR - DUAL RANGE revival

                Thanks Eric! I was going to add that, you saved me the effort!

                I'll add the installation instructions.











                Of all the paths you take in life - make sure a few of them are dirt.

                Comment


                • #10

                  Re: DOUG NASH ENTERPRISES OVERDRIVE - DNE2 - US GEAR - DUAL RANGE revival

                  Dog didn't get my arm but the slobber was a close thing.


                  No shifting in the JetBoat, but I've seen V-drives with gearboxes. Cool stuff!


                  Shot these pictures this morning. Got the crud so I didn't feel much like messing with it last night.

                  Selector all the way to left (rear), I believe this is direct drive.



                  Selector all the way to right (front) I believe this is overdrive. I may have them backwards, its hard to tell, and it seems to need a load to actually shift against.




                  Looking down the shaft towards the rear, you can see the top of the motor. Engaging the motor shaft to the screw shaft takes a little finagling, but if you use a screwdriver to pry the shaft into alignment its not too bad.



                  And in the other gear.
                  Last edited by STINEY; February 27th, 2014, 07:47 AM.
                  Of all the paths you take in life - make sure a few of them are dirt.

                  Comment


                  • #11

                    Re: DOUG NASH ENTERPRISES OVERDRIVE - DNE2 - US GEAR - DUAL RANGE revival

                    So where is this little beastie going to go? Behind the C6 in the cadicstang?
                    There's always something new to learn.

                    Comment


                    • #12

                      Re: DOUG NASH ENTERPRISES OVERDRIVE - DNE2 - US GEAR - DUAL RANGE revival

                      C6?

                      Right car, wrong drivetrain. TH400 fits this one, though there were adapters for all the OEMs best transmissions.
                      Of all the paths you take in life - make sure a few of them are dirt.

                      Comment


                      • #13

                        Re: DOUG NASH ENTERPRISES OVERDRIVE - DNE2 - US GEAR - DUAL RANGE revival

                        Been there, done that, with a unit purchased used for my '88 dually truck.

                        My DNE2 under/overdrive box (pick one choice only), unlike the GearVendors units, did not use the auto trans scheme of clutches and bands but instead ran/shifted like a normal manual trans with no syncro mechanism, and rather than a single countershaft running alongside the main there were four matched gearsets placed like planetaries. There is an enormous amount of torque capacity there so it can be used in any gear including first, and thus serve as a gear splitter unlike a normal internal overdrive gear which sees unmultiplied engine torque only. Upside is, well, you get a gear splitter...the downside is a not-very-high ratio and greater weight and internal drag.

                        The shifter motor unit is from a two-speed rear end application ("stepper" motors do not make enough power) and used a lead screw with a run off feature which prevents over-travel, and the aforementioned limit switches.

                        That all should have been reliable, but...

                        Mine was not looking too good when I pulled it apart and must have not been operable when I got it, unlike what the seller said. It came with receipts from prior gear, bearing and shifter motor repairs. One of the "new" countergears had some bad teeth, again - I guess, and I chose to leave it and it's opposite buddy out altogether since I intended to use it only in fourth gear and didn't need all that extra stuff spinning around. It need a mainshaft bearing again also, which was an easy source as a normal manual trans part. After doing all repairs and getting that shifter motor to work back and forth properly, mine worked a few months then was malfunctioning again with gear noise picking up about five minutes after shifting to overdrive, then the shifter motor died again. I intended to toss the motor altogether and convert it to a manual lever, which would work better w/ my manual trans anyhow 'cause you would be able to feel your way in and not just have the big crash. Before that happened I sold the truck...it had plenty of other reliability issues and I was done with it.

                        The lesson for me about my DNE2 was, why when OEM manufacturers design and build a transmission they also run and test for miles into the hundreds of thousands to see if it will actually work over time. What looks good on paper may not be up to snuff for actual conditions. I put ten good years on the Doug Nash/Richmond 5-speed in my El Camino, so I think they got that right...but the 4+3 deal they had on Corvettes does not have a good reputation with the 'Vette shop I work with.

                        With that said, hope yours works better than mine and good luck!
                        ...

                        Comment


                        • #14

                          Re: DOUG NASH ENTERPRISES OVERDRIVE - DNE2 - US GEAR - DUAL RANGE revival

                          There was a guy who worked for US Gear that had one in his 2nd gen(mid 70s?) camaro at maxton he said he did not shift the OD on the track more of a set and leave kind of thing. IIRC it would grind when shifted.
                          http://www.bangshift.com/forum/forum...-consolidation

                          Comment


                          • #15

                            Re: DOUG NASH ENTERPRISES OVERDRIVE - DNE2 - US GEAR - DUAL RANGE revival

                            It may have 4 lay-shafts, but I can tell you that no more than 2 of them will actually be transmitting torque. The 4 lay-shaft design is over-constrained. The precision required to evenly distribute tooth loads over 8 sets of meshing gears supported by 6 bearings is economically (if not functionally) unfeasible.
                            A key lesson learned by the major WWII piston engine manufacturers was that if more than 2 lay-shafts were required to carry the torque, you should switch to a planetary gear system with the requisite number of floating pinions captured between the sun and ring gears.

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