I have had a good look at the area in question on my 5th wheel after removing the pin box. (so far so good) .
As I mentioned earlier my 5th wheel hasn't had an overly amount of miles.
I don't think my Trailer is 'immune' to this problem, however, my rig was built in Oregon , at the West Coast factory on a Ziemann Chassis.
I plan to do some additional reinforcing much like "rmkpower1" has done and more on the other side of the pin box and frame webs as well.
This area is accessible by removing the under skin of the over hang.
In further precaution I now have a 'TrailAir Tri-Glide Air Ride' pin box....
..Soon the be road tested.
This pin box will greatly reduce any harsh road bump repercussion compared to the normal 'metal -to- metal' connection.
The 'TrailAir' Pin box will help reduce the stress from bounce and jarring on the frame of the trailer as well as the tow vehicle plus a more enjoyable ride in the cab.
The 'Tri-Glide' portion of the hitch will reduce the 'chucking' , which is common with the heavier trailers, ...I call it...the tug of war between the truck and trailer.
I will try to report my experience with the new TrailAir after my trip.
Oh , and an FYI... The Weld and Frame Failures are not just 2007.... and not just Wildcats..... I have read posts on other forums back to 2004....and even up to 2012...with frame flexing, weld breaks and frame tears.
However...it does seem to be very popular on Lippert Frames....and several Models of 5th wheel trailers that use Lippert frames and components.
From what I have been reading it seems to boil down to : a poor design using a poor grade of thin gauge steel, (high carbon content from China steel) .
Another Note: It is not just the 'Pin Box' (front frame ) area of trailers that have been experiencing failures. Other areas where the frame has been lengthened has seen web tears. (read on other forums)
IMHO.... It is a "beep-beep" shame that Lippert did not do some testing on the light weight and poor grade steel they were using in their frames.
They should be held accountable !
I write this only to caution owners to always inspect their rigs thoroughly in hope that any problem be caught early .
'07 WildCat 30 RLBS ~ West Coast Edition ~
Trail Air - Tri Glide Pin Box
2000 F350 DRW 7.3 Diesel Lariat 89k miles
Edge programmer, 4" SS exhaust turbo/back
Vancouver Island, B.C., Canada