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alexleblanc's avatar
alexleblanc
Explorer
May 25, 2016

how much pin box movement is normal?

I see this posted somewhat but I can't get a clear answer - my unit it still basically new I noticed that then I hook it up the distance from the bottom of the front cap and the pin box (checked pin box torque and its right on)gets closer by about 3/8" - 1/2" and while driving I can see about another equal amount of movement - I have one of those pin mount RV levelers mounted up there and its actually slightly scraped on the bottom of the front cap and the measurement is exactly 5/8" as far as I can tell.

I'm going to hook up the truck tonight and take some pictures and measurements.

here's a picture of the said level gauge that really helps me see the movement:



Alex

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  • N-Trouble's avatar
    N-Trouble
    Explorer
    May 25, 2016
    I would say normal. Metal flexes... Nothing is entirely rigid on any trailer so some amount of flex (1/2" or so) is expected. More than in inch I would be a little concerned. I had the exact same situation where my level (mounted in exact same spot as yours) made contact with the bottom of front cap while towing. Bout 1/2" gap while sitting unhooked.

    Most just don't notice the movement/flex but since you have your level there it becomes more apparent.
  • fj12ryder's avatar
    fj12ryder
    Explorer III
    May 25, 2016
    AFAIC there should be no movement. Any movement indicates flex somewhere and that means it isn't as solid as it should be. The amount of movement you've indicated points to a problem, maybe not serious yet, but as things flex, bend, and fracture it will surely get worse.

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