Leaf springs very noisy

[HIWYH8R]

My 94 YJ has had this problem that started about a year after I put on a RE 4" lift springs kit. When ever I turn to go up driveways etc and flex the suspension a few inches I get very loud snaping, creaking noises when the springs flex that I think is coming from the leaf springs. I have lubed the bushings often, inspected for shiny spots indicating movement, inspected the frame and mounting points for cracks, body mounts and anything else I could think of. Me and two other licensed tech's have not been able to figure out exactly were or why these noises are happening.

Just turning the front wheel toward a curb and driving up it with one front wheel is all it takes. Tried diconecting the sway bar, dousing the springs with oil, nothing works. The only thing that seems to cure it for a short time is when I go off road and flex the jeep good. Then the noise goes away for a couple weeks. And this cracking, banging noise is so loud that  pedestrians turn and look when they hear it. I also feel it in the floor really good. Thanks for any ideas you my have.

[TaTtOo]

Are your track bars disconnected? If either one of them are at all loose they will make quite a noise when they move.

[Gearhead]

Mine does that too , .... sometimes . I've decided to not worry about it. I've also decided to not worry about body damage , my paint , tires that get cut up on rocks , rust , dents and many other things that used to bother me.

[FiEND]

been there, sometimes still there... i laugh when people look.  wheeling/flexing makes it quiet so that's my fix, wheel more creak less.

[HIWYH8R]

The front track bar has been removed and the noise happend with it on and off. Noise seems to be coming from all springs but hard to tell. Also tourqued the shackle and eye bolts and tried leaving them loose to no avail. I kinda think it is the bushings but want to know for sure. They are red polyureathane bushings from my understanding.

Mine does that too , .... sometimes . I've decided to not worry about it. I've also decided to not worry about body damage , my paint , tires that get cut up on rocks , rust , dents and many other things that used to bother me.

Heheh, so your tellin me it's a Jeep thing and should live with it? :shock:

No really, if someone has better advice than Gearhead please post  :lol:

[HIWYH8R]

been there, sometimes still there... i laugh when people look.  wheeling/flexing makes it quiet so that's my fix, wheel more creak less.

That's also another possibility, my jeeps way of letting me know "it's time to go"  

[bae146]

Mine do that as well.  It seams to come from the front springs rear attach point.  I was thinking of upsizing the bolts to take up some of the slop.  I would have to drill out the bushing ans the frame to do this though.  I torqued the heck out of them and the problem was greatly reduced.

[BlackYJ]

My springs as well

It probably has to do with the fact that the axle wants to move back because of the bump, but due to the fact that the shackle is in the front, the spring is probably just binding a little.

[Ryans_GP]

What did you torque your u-bolts to after installing your leaf springs?

[HIWYH8R]

Mine do that as well.  It seams to come from the front springs rear attach point.  I was thinking of upsizing the bolts to take up some of the slop.  I would have to drill out the bushing ans the frame to do this though.  I torqued the heck out of them and the problem was greatly reduced.

Thats what I was thinking, that it seems to be coming from the rear mount of the front springs. The metal sleeves that fit inside the bushings have a very loose fit and that's where I suspect the noise is coming from. I have emailed RE several times about this but they don't seem to want to help. Are these bushings and sleeves a comon size that I could buy some better ones at National or Modern?

[HIWYH8R]

What did you torque your u-bolts to after installing your leaf springs?

Tight, very tight. Rechecked often. I have driven up and down a car ramp with a couple guy's laying under the jeep looking at things and feeling and you can feel the snapping in the spring but see no obvious reason. We don't know if it's the individual spring leafs binding against each other or if its coming from the front or rear mounting points.

[Asia]

I have a '95 YJ with Skyjacker/Rancho leaf springs and they are quiet but firm riding.  The funny noises I get in parking lots comes from the automatic locker in the rear.  I lubed the spring bushings/sleeves during the install but haven't done anything since.  I torqued the bolts to stock specs and found that the bushings at the shackle end of the springs was being cut by the spring eye due to the high stock torque setting.  I replaced the cut bushings and only torqued the "shackle end" bolts to 45 ft lbs and they are no longer being cut by the spring eye.  The nuts have nylon inserts and I recheck their torque values occassionally.  I have stock shackles and my spring's lift is 2.5"

[Ryans_GP]

The instructions for the RE 4.5" XD kit reccommends 65 to 80 ft.lbs, I torqued mine to 70 and the sounds seem to have diminished. I had initially tightened them to 100.

[hps4evr]

i bought a set of cheep lift packs for my '92 Yj a while back. my first test drive after installing them i had this problem. i changd the leaf packs since then and made a combination of rancho leafs and the old leafs. noise is now gone. i changed the spring bushings as well to proper poly bushings and lots of greese.
two problems with the old packs. 1st. the spring eye bushing at the frame mount was a poor design and actually shifted within itself and caused that horrid sound. 2nd. im thinkin when i mounted the springs to the axles and the shackles i did one side at a time. what i should have done was mount everything up on both sides then tighten down. that way everything is square and proper. im guessing if not done this way it may cause the spring to bind on the poly bushings. hindsight is always 20/20;)

[jeeppilot]

Had the same noise on my YJ with the 4" RE lift.  It stopped after a few weeks and now it sits about 1.5" lower on the left side.??