The cracks are a defect in the design that happened when they went from
a C channel frame to a double C box. The single C channel could twist
freely. When the double C twists, it stresses the crap out of the
lengthwise weld which gets weak due to holding mud and salt slush inside
it. It then splits and allows the two separate C channels to move
independent. The inner one will then kink (compression) crack up right
in front of the rear spring hanger.

Mine is totally blown out on the inside, so I had the outside C channel
plated on 3 sides along the area 4 or 5 years ago. The beefed up
Channel has held perfectly and I let the inside fall apart. Same for
the front passenger side.

There are companies that offer pre made plates for both the inside and
outside of the front and rear frame torque areas. So you can just buy
them 'first' rather than do catch up repairs when it breaks like I have
done....

When I get a new frame, I want it plated like that 'first' because I
twist the crap out of my CJ7 on trails.

I live in the salt belt and see 'most' CJ's with that rear crack
starting linearly on the bottom weld if not already broken open.... :-(

Mike

Jeepers wrote:
>
> In article >,
> Mike Romain > wrote:
>
> > If it is a boxed frame, the added torque on the mounts will increase the
> > cracking potential if you off road it. The frames like to torque crack
> > in front of the rear passenger spring hanger on the inside and over on
> > the drivers side frame behind the front spring hanger on the inside or
> > bottom.
> >
> > Mike
>
> Solution? Pix? Links? Thanks.
>
> --
> Member AAAAAAAA
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