Box to frame U Bolts

[Robert Sexton]

I have a C15 with a Australian No 1 timber body.The bolts that hold the body to the chassis are as described by Bob Carriere. The cup head bolt passes through a plate with a square hole to lock the bolt from turning and spread the load across the body floor and then another plate under the chassis puts the pressure across the bottom of the chassis rail.My body has a chassis stiffener/spacer grooved to fit the bolt and sit snug inside the chassis rail.
All very interesting,
Robert

[Jordan Baker]

I took another read through my spare parts book and found the following.

[Jordan Baker]

And I checked one of my other references and answered this question.

Anyway, per the chart the correct diameter should be 5/8's and the threaded ends long enough for two nuts.

[Hanno Spoelstra]

Excellent info Jordan, thanks for sharing!

[Jordan Baker]

Im about to install my box to frame bolts but I'm not sure if this is correct. The shop gave me plates long enough to clear the wider channel on the box frame. They said to then just use an impact gun and tighten them right up. My questions are is it fine to have a gap between the rods and the truck frame? On the inside do I need to make some hard wood spacers?

[charlie fitton]

Twist them so the the shaft of the bolt is as close to the frame as possible to avoid having the top and bottom plates flex under load.

[Phil Waterman]

Hi Jordan

Yes, too the wooden blocks, particularly as there are service bulletins to install blocking to CMPs in service.

Without the blocking would be careful about over tighing the bolts, would be concern about the open side of the channel bending.

I tighten my bolts by hand, and used Locktight on the threads, generally check them in my bolt check of drive shafts, links and wheel lugs in the spring.

Cheers Phil