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bob213's avatar
bob213
Explorer
Jun 15, 2021

3500 lb. axle castle nut

Does anyone really use a torque wrench to set the castle nut(50ft.lbs)? before you back it off and hand tighten it? If so, what size socket does that take? 1 1/2"? I think the 3500lb axle uses a 1" castle nut? Trailer is not here so I'm just trying to prepare.
Thanks
  • Procedure according to Dexter axle service manual HERE

    Page 56..

    "For standard grease or oil axles using cotter pin:
    1. After placing the hub, bearings, washers, and spindle nut back on the axle spindle in reverse order as detailed in the previous section on hub removal, rotate the hub assembly slowly while tightening the spindle nut to approximately 50 Ft. Lbs.(12" wrench or pliers with full hand force.)
    2. Then loosen the spindle nut to remove the torque. Do not rotate the hub.
    3. Finger tighten the spindle nut until just snug.
    4. Back the spindle nut out slightly until the first castellation lines up with the cotter key hole and insert the cotter pin.
    5. Bend over the cotter pin legs to secure the nut.
    6. Nut should be free to move with only restraint being the cotter pin."


    So, "approximately 50 FT LBS" which they mention using a 12" long wrench or pliers with full HAND force.

    No need to use a torque wrench when using 12" wrench or pliers as long as you follow the procedure above.

    Been doing that procedure the same way on 1970's and up vehicles since I started driving (that is the way my Dad showed me how to set wheel bearings) with no failures and the procedure works fine with trailer axles.

    The only difference between auto axles and trailer axles is the trailer axles use a very coarse thread and the castlated nut has fewer castlations which means not as fine of as a adjustment as auto axles and the bearings on trailer axles tend to operate with some slack or slop. Auto axles on the other hand needs zero slack so they use a much finer thread and the castlated nut has many more castlations.
  • Thanks Gdetrailer. Working oil trailer in remote location and hate to drag every tool in the box along to do it, but still want to make sure I have what I need. I should be good to go.
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    For the socket.. If all else fails take a nut to the hardware store and find the socket that fits

    And yes I like to use a torque wrench.
  • wa8yxm wrote:
    For the socket.. If all else fails take a nut to the hardware store and find the socket that fits

    And yes I like to use a torque wrench.


    "Working oil trailer in remote location..."

    Mmmmkay...
  • No socket needed.
    Crank the nut down snug with a crescent hammer or channel locks. Back it off until loose, finger tight, check for any end play. Should be imperceptible but rotate easier than when snug. Install cotter pin 1 slot looser or tighter than finger tight if it don't line up. Flip a coin on that one. Done.
  • There is no need to apply the 50 lb. ft. unless you just replaced the bearing races. The idea is to make sure the bearings are completely pushed in place. Just a firm tightening with a channel lock pliers, and then back off is all that is needed on subsequent work. The final adjustment is to have the least amount of play possible, but no preload.
  • Lynnmor wrote:
    There is no need to apply the 50 lb. ft. unless you just replaced the bearing races. The idea is to make sure the bearings are completely pushed in place. Just a firm tightening with a channel lock pliers, and then back off is all that is needed on subsequent work. The final adjustment is to have the least amount of play possible, but no preload.


    Correct!

    Which is why Dexter mentions in their service manual which I had quoted..

    Gdetrailer wrote:
    Procedure according to Dexter axle service manual HERE

    Page 56..

    approximately 50 Ft. Lbs.(12" wrench or pliers with full hand force.)




    No where in the Dexter manual that it states to use a TQ wrench and they specifically call out the use of a 12" wrench or 12" pliers which will typically result in near 50 FT Lbs of TQ which most typical folks can deliver with their hands.

    This is not a place where precision needs to be, just close enough will work fine..

    Now if you are assembling say a motor, you will need a TQ wrench for head bolts, manifold bolts, crank bearing cap bolts.. But this is not assembling a motor.

    No need to make everyone go out and buy a TQ wrench for this application.
  • This is what shade tree mechanics have been doing during my lifetime, not really knowing what we did was right: "rotate the hub assembly slowly while tightening the spindle nut to approximately 50 Ft. Lbs.(12" wrench or pliers with full hand force.)
    2. Then loosen the spindle nut to remove the torque. Do not rotate the hub.
    3. Finger tighten the spindle nut until just snug.
    4. Back the spindle nut out slightly until the first castellation lines up with the cotter key hole and insert the cotter pin.
    5. Bend over the cotter pin legs to secure the nut.
    6. Nut should be free to move with only restraint being the cotter pin."

    So hooray for us!

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