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Swapping out center arm

Discussion in '40- & 55-Series Tech' started by Degnol, Jun 16, 2003.

  1. Degnol

    Degnol

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    I'm changing out the old pin style centerarm on my '66 FJ40 for the later tapered, adjustable one. The front x member is not perpindicular to the frame horn so I'm making a shim for the front of the x member to line it up for mounting. Question is, shouldn't I make one for the inside of the x member, too? If I don't, there will be some "bad torque" on the bolt.
    A buddy is making the shim on a Bridgeport, so he could make one twice as wide, cut it in half and I could flip it and use it on the inside.
    Second question, should I weld the shim(s) to the crossmember, or just bolt through them? Grade 8 bolts ought to do the trick, eh? :dunno:
     
  2. Pete_S

    Pete_S

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    I JUST did the exact same thing! I took off the old center arm pivot and boxed in the frame channel. The front cross member, as you noticed is not perpendicular to the frame. I took a piece of 3/16" X 1 1/2" flat stock and formed some type of a right angle bracket.
    I tacked the frame boxed section, and then held the new pivot in place to see where the metal angle (90*) +/- would need to go, against the crossmember. I checked that the face of the angle was plumb and square to the frame boxed portion.
    From here I marked holes..............for the grade 8 bolts.
    PRIOR TO WELDING THE ANGLE I drilled the lower hole and then had the bolt in there as you noticed the angle would be a killer. The top bolt is NEAR the top of the crossmember, just fitting the head in, but goes through BOTH angle and crossmember.
    Then once cooled, I drilled and mounted the new pivot.
    I've just been toolin' around here and no serious road driving but yet to notice a difference, other than no more klunking noise.
    Watch for needed access points to mounting bolts, as in don't weld yer self out of reach of tow hook nuts, etc with the box in.
    email me if you'd like me to attempt to send you a picture of what I did.