GlennH

Whos got them and at which height? Also a std or automatic? How long have you been running the lift without vibes? How are the joints?

JE Reel seems to be quite the expensive route...

wayoflife

Technically, you shouldn't have any vibes if you still have stock drivelines especially considering they have CV joints. Now, if you have an aftermarket double cardin U-joint style shaft, you will have them if you do not dial in your rear pinion angle to be in line with your driveline. Up front, you will have more room to play with as the shaft is so much longer than the rear.

Mike JK

I have an 07 2 door Rubicon automatic and I had driveline vibes after installing a 2" BB.

The vibration was only present at 60-65 miles per hour and was rythmic, meaning it was in, out, in out, almost like a throbbing. It was slight, but noticeable. No way to pretend it didn't exist and make it go away. The ride quality also deteriorated noticeably.

Yes, it was installed correctly, yes, it was installed by someone who knew what they were doing, yes, I had an alignment (didn't need one, just checked it), yes I crossed my t's and dotted my i's.

I drove about 200 miles then ripped the lift out and put everything back the way it was. No more vibration.

Now I don't know what to do about a lift, because when you add up new driveshafts, control arms, track bars, etc., it adds up to a lot. It's cheaper to replace skid plates.

GlennH

having high speed vibes is one thing, but low speed ones are another...

TEEJ

From a foresnsic stand point...there are some items that might explain your issues....considering you had them, and others did not.

1. "Installed correctly" - maybe, maybe not, but hard to screw up, so probably.

2. "Checked alignment, and didn't need one" - oops...how is it POSSIBLE that you can lift it, and not pull the steering towards the pitman arm, or the axles closer to the frames at the track bars mounts? - Sounds like this was an issue....especially as a lifted rig doesn't use the OEM ALIGNMENT SPECS....they will be wrong.

So - One major opportunity for a screw up.

3. I don't remember how many t's or i's were under there...but, it sounds like you had someone else do the work, you trusted them, they convinced you over the years and years you knew them that they knew what they were doing...maybe did lots of these things for lots of people before you, etc....but its hard to see where you crossed or dotted frankly.

So - In summary (For the readers, its too late for you....your mind's probably made up, etc...) - It probably needed a different alignemt spec...short shafted jeeps are notoriously easy to get a driveline vibe on with even a mild lift...but you should have been able to go to closer to 3" before having those problems if it were set up right.

Plan B...you need to re-clock the drive train...maybe yours is one of the "BARELY within spec" types that left you more vulnerable, etc, than other people.

You can easily check pinion angles and so forth to see if its tilted more at stock height than expected...it might provide more info as to why the jeep gods hated you, etc.

Mike JK

The kit was isntalled by mechanics under my strict supervision and control. I could have easily installed it myself, but without an air compressor it would have been a long and painful process and I took the easy way out...a way that still gave me full control over the installation.

As for the wheel alignment, yes, it was out of specs in some areas, but the wheel alignment guy said the Jeep lacked the adjustment points necessary to correct what was out of specs and said it should drive fine with no tire wear but the steering would be more twitchy than before. If it gives you any further clues as to what happened, my steering wheel was perfectly centered after the lift also.

Before removing the kit I took the Jeep to a guy that's been building hot rods longer than I have been alive, and he drove it, examined it and pronounced that the vibrations were caused by the rear driveshaft angle. From my own limited experience, I concurred.

Wheel alignment does not cause driveline vibrations of the type I experienced. I know that's not something I can convince you of without having been behind the wheel, but you'll either have to take my word for it or write me off.

I like the "barely within specs" idea. Now what do I do about it without buying arms and track bars?

TEEJ

OK, I know what you mean about th difference between a driveline/alignment vibe....so I'll take your word for your observation on that....so -


Well, re-clock the drive line.

Rotate the pinion angle to point the input more directly with the new ride height...if "Barely sped's", etc...the obvious way to correct it would be to rotate it to point up a bit more to relieve the angle.

On the TJ's, we'd tilt the engine down at the rear by using taller front engine mounts....have not messed with the JK in tha regard, or seen similar solutions....so I'd essentially look at how to rotate the diff to tilt at the input...and pick the simplest/cheapest solution with strength.

START by measuring the pinion angles you HAVE now, and be sure you're barking up the right tree though...the guess is that its at the edge of what's considered OK, or maybe as far as not ok, who knows...so far, everyone's jeep has been different...even mounting holes for things seem to vary from jeep to jeep in the same model run/yr etc.

Your's is probably no exception.

So -

1) Check CURRENT angles...see where you're at.

2) If clocked to the end making you more susceptible to this sort of vibe, then consider alternatives to correct it.

Hope that helps!

jeep329

Just a quick note about Vibes and lifts. My stock 07 Jk had vibes on the freeway at about 60-70. It was very slight on the steering wheel. Went away when I put a 2" BB in....odd I know...

wayoflife

Speed related vibes especially when they are at the higher range are almost always tire balancing problems. Vibrations in your drivelines would be felt most at lower speeds and then would fade away the faster you go. This is a fact. Because the drivelines have CV joints, they WILL NOT give you vibes just because you lifted your Jeep any less that would a vehicle running IFS. CV's are designed to run vibration free at steep angles.

wayoflife

Sorry, but this would mean nothing to me and explains nothing.

That's because you lacked the adjustment points necessary to correct what was out of spec. Your steering was twitchy because you needed more positive caster and depending on how big of a tire you were running, a toe-in adjustment as well.

Hotrods and lifted Jeeps are like comparing apples and oranges and unfortunatly, your friend doesn't know what he's talking about. If you had a double cardin u-joint style drive shaft (w/o adjustable rear control arms to dial in your pinion angle), his assesment would be correct but assuming you still have factory drive shafts, this would absolutely be untrue. CV joints are designed to run at steep angles and not have vibrations. Granted, if the angle is too steep, it can cause the premature wear of your CV boot which would ultimately lead to the failure of your joint but that's about it.

No, but tires not being balanced would.

If you are having vibrations at 60-70 MPH, try getting your tires balanced again. If you are having handling issues (i.e. twitchy steering), you need more positive caster and although you can use cam bolts to do this, I wouldn't recommend it. I would recommend adjustable front control arms to do this. Other than that, not a whole lot you can do without it.