Power lok rebuild questions

Discussion in 'Early CJ-5 and CJ-6 Tech' started by 1977redcj5, Apr 14, 2010.

  1. Apr 14, 2010
    1977redcj5

    1977redcj5 New Member

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    I have power locks in the front and rear of my CJ and they have served me well so far, but a jeep is never done.

    I rebuilt the 44 rear with an aggressive rebuild kit less than a year ago and it has worked well, but I want a full locker in the rear so I'm putting in an ARB.

    Because of the risk of breakage I want to keep my front dana 30 Power-lok rather than locking the front, but want to make it lock up stronger. How do I know if it is worn out (both tires still spin when jacked up and one is turned) and how do I rebuild it or shim it to make it more aggressive? I have heard of people putting shims in them, but am not seeing the specifics on how thick the shims are. I have also heard of people doubling up on the cones, but I'm not sure my frond dana 30's powerlock has the cones or not since I haven't taken it apart.

    I wonder if I can even just shim the clutches I have now if they aren't worn out.

    Please help me build a more aggressive powr-lok.

    Thanks for your help.
     
  2. Apr 14, 2010
    nickmil

    nickmil Super Moderator Staff Member Sponsor

    Happy Valley, OR
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    Typically what one does is remove one of the flat plates and replace it with the same thickness belleville spring (the dish shaped clutch plate). This will increase preload on the clutches and side gears. Carefully modulating the brakes can also help the clutches initially grip better as well.

    To test the Powerlock clutches typically you lock in the hubs, transfer case in neutral, wheels chocked, etc. etc. Jack up one wheel then put an adapter on the lug studs and use a torque wrench to test the breakaway torque of the clutches. According to the TSM/FSM I have on hand that minimum torque should be 40 lbs. ft. of torque. Higher is better but that is the minimum.
     
  3. Apr 15, 2010
    1977redcj5

    1977redcj5 New Member

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    thanks nickmil

    If I buy a rebuild kit will I be able to take one of the cone washers out of the clutch pack already in my locker and use that with the new clutches (minus one disk)? Or do I need to fine one separate?

    I have found several sources for clutch kits including randy's R&P, but is there a source you recommend?

    Also when you say put an adapter on the wheel is it some sort of adapter that centers the torque wrench or is it just an extension so you get past the tire?

    By the way I'm in Portland too and have really had good luck with the power locks in Tillamook State Forest - even getting up can opener with them, but I'm swapping our my rear dana 44 power lock I just rebuilt with an aggressive kit for an ARB for a little more performance, but I will stay with the Power-lok in the front to avoid breaking my 30.
     
  4. Apr 15, 2010
    windyhill

    windyhill Sponsor Sponsor

    PA
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    I'm pretty sure Herm has them as well, and possibly discs individually?
     
  5. Apr 15, 2010
    nickmil

    nickmil Super Moderator Staff Member Sponsor

    Happy Valley, OR
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    Very cool! Yeah, the Powerlock in the front works good for TSF and the slick clay up there. Been up Canopener, 7 up, Saddle up, Cedar Tree Trail, etc. many, many times. As Windyhill mentioned Herm Tilford may have individual clutches if you need to purchase them. Six States Distributing is the local Spicer Dealer on Columbia Blvd.
    R&P usually has some loose clutches as well. They are between Canby and Oregon City. 503-557-8911.
    If your old clutches are in good shape and match the thickness of the new discs you can certainly mix and match. I'll be home this Sunday and if you have it out I'd be happy to help you go through the Powerlock. Doesn't take long at all and I have a solvent parts washer to clean everything up in. Just pm me if interested and I'll give you my #.

    The adapter I'm referring to bolts to the lug studs and centers the extension for the torque wrench. If the torque wrench is off center of the hub that will skew your readings but at least will give you an idea if you're even in the ballpark.
     
  6. May 23, 2010
    1977redcj5

    1977redcj5 New Member

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    Hey Nick,

    Sorry I haven't responded to your offer to help me with my powerlok. I really appreciate the offer, but I think I am going to leave my front powerlok as is after your info and a little more research.

    I built a little rig to test the torque on my front powerlock. I built a steel plate that would allow me to place a bolt on the center of my front hub to hook my torque wrench to. I left one tire on the ground and locked in the hubs. When I put the torque wrench on the tire in the air I quickly got up to 70 FT LB to turn the tire. I didn't keep moving up in ft lb's because the bolts I had the plate screwed into the hub with started to bend and since the number for a rebuild is apparently 40 and under I figured I was in good shape. I'm going to run it as is this summer and maybe add some shims next winter to lock it up tighter.

    There is a pic of the rig I built at:

    http://s632.photobucket.com/albums/uu49/JeePs187/?action=view&current=torque.jpg

    The interesting thing is that I rebuilt the powerlock in my rear dana 44 last winter with an aggressive kit and you cant even get the wheels to spin by hand the clutches are so tight so that may be my eventual goal in the front.

    I actually pulled out my rear dana 44 powerlock two weeks ago and put in an ARB. Kind of bummed I wont have my powerlok in the back any more (only wheeled it twice), but I'm sure the ARB will shine next time I head out and hey I still have a front powerlok.

    Thank again [​IMG]
     
  7. May 29, 2010
    jzeber

    jzeber Sponsor Sponsor

    San Jose, Ca
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    So this got me to thinking about my set up in my front 27. I checked it out and had a reading of 55 ft. lb. Better than the minimum of 40. I know it is personal opinion but is it worth a rebuild? I have had a couple of occasions where one front wheel was 1 - 2 ft. off the ground and the other would not grab.....maybe a good thing!
     
  8. May 30, 2010
    nickmil

    nickmil Super Moderator Staff Member Sponsor

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    I would say a good thing. Some slip helps keep the axles, u-joints, and ring and pinion alive on the 25's and 27's. :beer:
     
  9. May 30, 2010
    jzeber

    jzeber Sponsor Sponsor

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    Makes sense.
    Thanks Nick
     
  10. Jun 15, 2010
    sgogpn

    sgogpn Sponsor Sponsor

    Glendale, AZ.
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    I had PL's front and rear on my 75 for years before going to a Detroit in the rear. I still run a PL in the front Dana 30. It's been there for 19 years and has been trouble free. I can tell you from experience that shimming the clutchpacks is a doable thing. I shimmed mine about 10-15 thousandths each side and it tightened it up enuf to make it harder to steer.:) You can use pinion/carrier type shims or just make your own. You can actually turn them into a spool if you shim it too much. I purposely run the PL in the front because the clutch type limited slip gives decent performance while still offering a little give if you get the tires bound up. I did snap an axleshaft once when I got a little goofy with the skinny pedal when the right front bounced up and came down hard but I can live with 1 axleshaft every 19 years.:) The PL is a great unit; it was good enuf for the factory to offer them as an option for years. I also run them front and rear in my 67 with an F134 and T98 with stock tires and it'll go anywhere I want to go.:)
    FWIW,
    Mike
    sgogpn
     
  11. Dec 8, 2017
    Running Bare

    Running Bare New Member

    Enumclaw WA
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    you folks running spicer power locke in dana 44, Do you use any special additives gear oils or just regular 90weight gear oil? thanks for the info
     
  12. Dec 9, 2017
    NCRenII

    NCRenII Member

    Far Nor Cal
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    gear oil with gl5 rating (extreme pressure). If new assembly I use an extra bottle of modifier for break-in, and then the straight gl5.
     

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