The bushings in question are for the Front Control Arm (rearward) or Wishbone (item #2 on the attached drawing) I replaced the stock bushings in July 2016, then the car went into storage for 9 months. I drove the car a grand total of 6k miles before the bushings developed slack between the sleeve and the poly material.
Symptoms were similar to warped rotors under heavy braking, severe bumpsteer, inability to align the front suspension, and instability at higher speeds.
Warranty: PowerFlex offers a lifetime warranty. I contacted the retailer (WhyBee.com from the UK) and they immediately setup the claim. Two or three days later there was a new set of bushings in the mail on their dime (or pound, whatever). I have not received the new bushings yet, but the tracking shows they are somewhere out of customs heading to Kansas.
Warning: The part number I originally purchased appears to have been superseded (PFF5-702
), yet lots of retailers still sell the bushings. PowerFlex shipped out a different part number, PFF5-1002
, as the replacement. I have yet to find a retailer that lists the new part number as fit for the E60 chassis.
I will update this thread once I've had a chance to install the new bushings.