There are isolators top and bottom in stock form. The upper are rubber-like. The lowers are plastic and have tabs that engage the 3 holes in the axle spring perch. Some say the lowers aren’t necessary. In support of that idea, the front springs don’t have them. I replaced my rear lower isolators recently with Delphi parts from Rock Auto.
Did they make any difference? Less noise?
I doubt they do (lowers, I mean). But I haven’t done the experiment with and without. I replaced my uppers and lowers when I had my axle out because my ‘97 had them and the original lowers fell apart on removal and the uppers came with the lowers. Intuitively, I suspect the uppers may make at least a little difference in NVH but maybe not enough to be noticeable in a TJ.
So I guess the consensus is they don't really matter....so I'll install the springs tomorrow without.
Thanks All
NVH?
Nasty vehicle harmonics?.........