Well, here's the deal...still no solution, though I'm pretty sure it is the rear springs/insulators. There's really nothing left. Every bit and part and been removed and re-lubed. I removed everything from the trunk. A silicone sprayed all the exhaust hangars and on the spring insulators themselves. I've wrangled the exhaust in every direction to see if made a noise. I've pushed, pulled, poked and prodded everything I can find under there. I can't reproduce the sound by pushing down on the car, but every once in a while I can get a very small similar sound if I push up from underneath, but still nothing to really isolate the noise. The noise is most certainly only occurring when the rear axle moves with a jolt or extreme ranges. I haven't removed the insulators to look at them, but I figure I'll just order new ones and be done, then I'll really know. I think it is the top insulators and maybe just the right top one, based on how the sound seems like it comes from the rear package tray/behind the rear seat.
2008 Bullitt|Roush M90 w/2.57 pulley & CAI; 90mm MAF; Steeda-UCA, LCAs, Ultralites, links, mounts; MM CC plates; Bilsteins; GT500 FCAs; Brembos; Roush shifter; GT500KR axle back; etc
1969 Coupe Restomod-never complete!
2008 Power Wheels Bullitt Clone
Mustangs from the past: 66 coupe, 69 Coupe, 69 Grande, 2001 Bullitt, 2011 V6
Last edited by rangerdoc; 11-19-2015 at 03:42 PM.