The issue we had with units in '04-'05 was problems with the outriggers rather than the frame itself. But that still becomes an inspection problem. Some outriggers were breaking welds at the I-beam. Others were developing a crease and fracture at a 45 degree angle at the top of the outrigger. The fractures were more difficult to see, all dirt had to be washed off the outrigger and a strong light used to see the issue in the shiny paint. This would be impossible to see with any type of undercoating.
The outriggers are what really holds the trailer body to the frame and they actually sit about 1/4 inch higher than the top of the I-beams. So, the trailer floor joists really don't contact the I-beams normally. On fivers, the floor joist run parallel with the I-beams and a total failure of the outriggers would allow the body to drop the full height of the floor joist until the plywood decking was sitting on the I-beam. There are two types of outriggers, the ones under the slide outs are smaller and thicker and not suspect. The thin gauge main outriggers were the problem ones. Lippert fix was to weld 1/4 inch plate steel to them to keep them from flexing and to enable better welds. CR and Lippert have not changed the metal gauge for the outriggers since this issue, but may be using better strength steel.
Texas Baptist Men-Retiree Builders member since '01
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