i'm going to get some steeda lowering springs and i was wondering if the polyurethane spring isolators are needed? my car is three years old with 7000 miles. would the old ones do just as well? any pros or cons would be appreciated.
If you don't get them, expect about 1/4 in more of a drop. I didn't put them on my Ford C Springs and it has been fine, there is some rattle from the rear end, but all within limits. I wrapped mine in some electrical tape too.
without isolators, you may have metal to metal contact, adding harshness and some noise.