I hate poly, it squeaks. Won't ever use it.
I realize not everyone will have squeaks, but it depends on how and where you use it. Since I've already been driven crazy by the noise, I won't take the chance again.
I think I've read 100 plus threads on this lol. But other than people have opinions, and strong ones ...I dunno if I know all that much more about poly vs. OEM choice-wise then I would have if I simply flipped a damn coin LOL.
I'm looking for some balance, considering that I already have the leaf packs (new Crown Upcountry replacements ...the QT HD OEM packs), and already have the Energy Suspension rear leaf poly bushing kit (I only ordered 'em because it was a "good deal" IF I bought them with Reflex 911027 rear shocks ...and then the seller cancelled on the shocks - didn't have 'em - and had already shipped the poly kit when I called to cancel that), sitting on the floor of my garage.
But I picked up some unexpected income this month (still waiting for the checks to come in, but they're reliable clients), so I'm seriously considering an HD Engineering shackle relocation kit as part of the project ...which that, and the UC springs, should make for a 2 inch lift (which I've decided I'd actually like to have, since I've now seen enough pix of XJ's with 2" lifts running 235/75R15's, which helped me think it won't look totally stupid ...especially important, as I just shod it with that size new GY Wranglers on TJ Canyons, so I'm
not changing that part of the equation).
Does a
shackle relocation kit make a difference in whether poly bushings are a bit more acceptable?
Or what about
shackle sliders instead (they're not that much more expensive, and I)? Would that make a difference in the use of poly on the packs (after all, you're eliminating the shackle)?
Its the "how and where you use poly" that is my problem, lol.
Here's what I think I do know.
Ease of installation? - No contest. Poly wins. A little lube and a BFH and you're good. No press. No fuss. No muss ...and I already got a BFH.
Squeeks ...make sure to lube the holy crap out of poly during the install, and add this an an item to your regular maintenance lubrication list. And do NOT over-tighten anything (i.e., the bushings, not the u-bolts) until you have the vehicle back on the ground, with the full weight of the vehicle on the leafs. And maybe the squeek issue is mitigated to "down the road". Maybe.
Longevity? Poly lasts longer, maybe ...if it was a quality kit, and if it was installed correctly, yada-yada. That said: rubber lasts "long enough" (
years).
Flex? Who the hell knows lol ...there's some very, uh, conflicting opinions on this. I think there's a consensus that poly should not be used in the sway bars, and the lower control arms (not that I care about that right now: the question is whether they're okay in the leaf packs fr/rr or one or t'other).
As for acceptable poly "locations" re: leaf springs ...here's what I
think I have learned so far, from various comments.
Front rear leaf bushing? - Poly is probably okay. It depends upon whether
leaf twist is or becomes an issue (the trick being whether you can pre-determine this lol).
Rear rear leaf bushing? - Maybe. Maybe not. Who knows. See the "leaf twist" issue, but
do you get leaf twist with shackle sliders? Dunno.
Shackle bushing? - Probably not. Sliders eliminate shackles though.
So. Basically: I got nothin'. Yet.
...but boy-oh-boy, am I getting really good at searches.