Originally Posted by Cherokee95kid
Metal budget biosts will end up doing damage to the spring perch that's why they are poly because thy absorb the abuse the springs put on the perch.
Interesting opinion... tell me, I've been using Aluminium spacers for about 20 years now, on two Jeeps (XJ/ZJ), with over 250,000km combined mileage. At what point should I start looking for this damage?
I cut a piece of inner tube rubber to put between the spacer and the perch, and then reused the stock isolator between the spacer and the spring. No problems I've ever seen.
Here are some specs I found for ya. Mine actually have a taper turned into them to transition between the two IDs, which more closely mimics the shape of the spring perch, but I'm sure these'll work great too:
I got these specs from an INSANE facebook page on incredible XJs. A lot to learn from the pics on there!!!