We had similar problems with the stabilizer bar under a 30 ft 500 series flex header. Acreage harvested using the flex head is about 1000 to 1500 acres per year. The stabilizer bar has no adjustment or any give for any fore and aft movement arising from wear in the parallel link arms. We regularly broke the bolt ends off of the socket assembies at least twice a season. Our solution is in Hyper Mods- Header Mods and Tips- Heddy's Hyper Mods- Stabilizer Bar. We have used this set-up with out any problems or repairs for the last 3 years.