OK...I went and took pictures of what I think is a problem with after market bumpers/body damage....
note this is the ARB bumper...the one trail teams use...
Note the size of the gap between bumper and body....at least 1 inch
note the flags on mine...still rubbing at over 1 inch gap
note the body rubs on the side
I have seen a few bumpers with the bumper smashed right up against the front grill...This WILL cause damage in the long run because the frame and the body are NOT connected(note the rubber bushing you are all talking about)
there HAS to be some play in that area
please go check your bumper and tell me if the bumper touches the grill AT ALL...or is there a gap...the gap is absolutely nessisary if your are going to flex this truck as far as some of us do....to be continued...after you gap check
HOMEDAD may be onto something here. I took my laptop out to my FJ to try to locate the exact locations of failure on my rig. I looked a the suspension and tried to picture the wheel travel. It would be very difficult if not nearly impossible for the suspension to transmit the required stress to those points of the body to make it fail that way. Ditto for the wheel travel.
The wheelwell liner is plastic and sheet metal spot welded to the body structure. Pounding on the wheelwell will apply shear stress to the joint and will fail the welded areas first.
The area of the body where the cracks developed are in the crumple zone of the body and it does appear to be slightly compressed in the photos. If the bumper is transmitting stress directly to the body it could failure.
BERND: Did you hit anything with the front bumper?
A 3-D CAD model of the suspension and body could really help clarify what is going on.
Either way, it's difficult to identify how "normal" use in legal terms could have caused this damage.