finished OME lift - vibrations?

[BLUTO]

I just finished installing my 3" OME lift tonite. After talking to a rep at ARB (sat REAL high in rear), I filled Jeep with 350# worth of boulders and proceded to beat on it :D . I did not have any vibration issues at ANY speed :) . I wheeled it a little and then took the boulders out and remeasured the height. It was now sitting at 34" from garage floor to bottom of wheel well moulding all the way around (with boulders it sat 1-1/2" lower in rear and 1/2" in front.
Now I go for another ride and at ~65mph I start to get a little vibration from rear. At 70mph to 75mph, it is more pronounced but not too noisy (it does pick up a little upon accelleration from 65 to 75 mph). At 80 to 85 mph it appears to be gone. I'm running 31 x 10.5 x 15 ProComp AT's (30" tall :rolleyes: ) AW4, 242, and stock otherwise.
My question: Does anyone think that I may get away with a 1/2" TC drop vs going the full inch?....since my vibrations only appear between 65 & 75mph. This gives me an extra 1/2" clearance and doesn't change the front angles too much either. Has only 1/2" been tried before?

Thanx for your continued input,
BLUTO :)

BTW: LOVE that new OME lift :loveu: and steering stabilizer! Nothing seems to faze it now! The poly bushings make a little "flex" noise on the bumps and dips, but smooth and quiet otherwise :cool:

[poppabear]

what year?

if it is post 97 then you might need to shim the rear springs and/or the full tc drop.


why did you use poly bushing?.. you are supposed to use OEM rubber bushings.

another option is too add a small spacer to the front and add some MJ shackles to the back.. that may rotate the pinion enuff to fix the vibe.

[Kejtar]

what year is your xj? what t-case/tranny/rear end combination do you have?
Also do you have shims in the rear? how does it look when you look at the tcase output vs the rear axle output angles? Kind of parallel but steep angles between each other? or not?

Kejtar

[TOZOVR]

I'd try a 2° shim in the rear (thin end forward). Also be sure your tires are balanced (this is often the culprit)

RJ

[BLUTO]

Sorry,...forgot to post year and axle (2000 and 3.55,AW4, 242, and D30 front/D35 rear).
No I haven't shimmed it yet, I think that's where I try out several different shims 'till it's gone OR does somebody have a formula to take the guesswork out of it? ;)
I didn't know that Urethane bushings were verboten!? Seems like a lot of other guys use them and like them. I figured there would be a little extra noise, but it shouldn't affect vibrations. I also plan on using them on my sway bars. The only time I hear them is on rough roads, 90% of my driving is on pavement.
Tires are brand new and balanced, though the tire guy said that one tire didn't balance-up perfectly, it is on the rear. I have my old stock tires/wheels still. I can put them back on to see if the vibrations go away (they are 2" shorter in diameter than my 30" tall new ones). Would that affect my pinion angle and fool my experiment to eliminate bad balance as cause?
The axle and TC yoke angles are fairly(by eye) close to each other in angle. Though, there is a slight bend in angle between pinion/axle yoke and driveshaft yokes. By shimming 2*or 3* I may be able to make everything straight? Any good technical write-ups (with pics) that you can direct me to?
Thankyou for your continued support, I'm going to send in my membership fee and become an "honest wheeler" :angel: ....hope you guys take PayPal,

BLUTO :)

[TOZOVR]

I'm ran a 2° shim at 3 and 4" of lift, worked out for me very well. You can also get an angle finder from Home Depot and find out excactly what you need. I wouldn't think more than 4° but 2 is a nice starting point.

[Talyn]

I hav a XJ withe teh same specs as yours (2000, AW4, NP242, 3.55). It has 3.5" in the rear. I tried several sets of shims and even tried to measure the angels to get the right set of shims. No luck.. vibes were still present. I got an SYE and that took care of it. Don't know if a TC drop would do it for you or not. I also drove around with vibes for about 6 montsh with no ill effects to date. BTW, you figure out how much lift you have by measuring from the lower edge of teh fender flare to the center of the wheel, than subtract those abount from stock measurements in the same locations. Stock measurements are 17.5" front, 17" rear.

-Chris

[TOZOVR]

Very true, a SYE kit and CV driveshaft will indeed cure what ailes him, but there's a good chance he'll need to shim regardless.

[Talyn]

Originally posted by TOZOVR
Very true, a SYE kit and CV driveshaft will indeed cure what ailes him, but there's a good chance he'll need to shim regardless.

Oh yeah.. I didn't say he didn't need to shim... I have 2.5* shims in mine with teh SYE.

-Chris

[BLUTO]

Did you guys have vibrations at most speeds or just at a certain speed? As I said earlier, I had NO vibrations at ALL speeds when vehicle was loaded down and dropped 1-1/2" in rear.
I can see how the driveshaft-yoke angles are a little off right now and hope the shims will bring it back in-line. Did adding the shims create any noise from vibration or rubbing?....Did you do anything special to them when you installed them?

BLUTO :)

BTW...can you describe the noise of your vibrations (ocillating? humming? grinding? high pitch?)
Mine occur under accelleration between 65 & 75 mph OR at a steady state speed of 70 - 75 mph.

[RCP Phx]

I would call mine an "oscillating drone"!

[Locrdup]

I have a 2000 also and what worked best for me was to install an AA HD SYE and Tom Woods driveshaft before I even lifted. ;) Best $500 I've ever spent too. :angel:

[94_2wdcherokee]

what is an OME lift? what does that stand for?

[BLUTO]

OME .....(not to be confused with OEM: original equiptment manufacturer).... stands for Old Man Emu. They are the suspension division of an Australian company (ARB), that makes a LOT of quality aftermarket parts for 4wheel drive vehicles from all over. The OME suspension is top notch ;) , in my 24 hours of driving on it....and many other peoples opinion on this forum. They are a little bit pricier than your average lift kit, but you definately get what you pay for! :cool:
BLUTO :)

[Locrdup]

Originally posted by BLUTO
They are a little bit pricier than your average lift kit, but you definately get what you pay for! :cool:
BLUTO :)

Then I think you ought to pay more for an SYE. ;)

Seriously I can't believe some folks have newer XJs lifted over 3" and no SYEs, especially when they spend extra $$ to get a OME. Plus you should see the AA output shaft compared to stock!

[BLUTO]

I have read that some people NEVER have vibrations after a lift of >4", while some people get vibrations at <2" of lift :confused: .
Each vehicle is somewhat different than the next. I will START with $15 worth of shims and if they are still there, drop TC and if that doesn't work...SYE ;) No need to go to the most expensive solution first, if the others do the job properly. My rig is not a "Bogger" or RockClimber....just a daily driver with a little offroad thrown-in on occasions.
If I can avoid having to install a SYE, then I'll be in a better $$$ position to get some posi's and gears. ;)

BLUTO :)

[Kejtar]

Bluto, I have a 98XJ and I thought the same as you did.... now finally after I put on the SYE, I will have to say that it rides better then it did stock! Also if you got good droop in the rear, make sure that you're not going to drop the shaft when you articulate.

Kejtar

[Talyn]

Originally posted by BLUTO
I have read that some people NEVER have vibrations after a lift of >4", while some people get vibrations at <2" of lift :confused: .
Each vehicle is somewhat different than the next. I will START with $15 worth of shims and if they are still there, drop TC and if that doesn't work...SYE ;) No need to go to the most expensive solution first, if the others do the job properly. My rig is not a "Bogger" or RockClimber....just a daily driver with a little offroad thrown-in on occasions.
If I can avoid having to install a SYE, then I'll be in a better $$$ position to get some posi's and gears. ;)

BLUTO :)

Yes, but the SYE isn't only to elliminate vibes.. it is to relieve stress on teh transfer case's out put shaft and out put bearing.

-Chris

[MAC'sXJ]

Just finished a 3" lift on my '01 XJ, and I too had a bunch of weird vibrations on the fore and aft sections of the driveshaft under accl. and decl. Trust me, add the T.Case relocation kit from Skyjacker and your troubles should be minimal, mine were. You could also make it with square box steel and save around $30. its simple. Good luck.

[bgcntry72]

Kejtar is right on. I had my OME at 2.5" for awhile and I thought it was nearly silent on the road. After I went to 3.5", there was some noise, but it was tolerable. Once I got the SYE on I could not believe how much smoother and quieter it was. You get used to noise pretty easy driving a Jeep, so you probably think you have no vibes. The harmonic vibes that you don't 'hear' or 'feel' to be excessive are still slowly but surely shaking, and ruining, your driveline. Just get the SYE. I went with an RE hack and tap and got it with the shaft for about $350, and it is worth twice that much. You should pick something besides your driveline to cut corners on. My $1.73.

[Kejtar]

Btw, if you're planning to do a tcase drop you will encounter a big problem: rocks will make the crossmember wrap itself around the drop :( How do I know? I have a pretzel of a crossmember to prove it :D

A tcase drop kit should be "WIDE". IF I had to make one I'd recommend taking 2" flat stock and stacking it as needed. Or..... I'm not sure who'se I had, but it was two huge (about 2" in diameter) pieces of aluminum cylinders. If you use small ones, expect pusshing them up through the framerail sooner or later (along with wrapping the crossmember to a pretzel around them.

[JMLichner]

A SYE is well worth the price, I have the Hack and Tap also about $80.00 from Dgp. Best investment so far, I know the drive shaft price hurts, but you will thank your self down the line.

[poppabear]

SYE you be the first MOD is you plan on lifting and wheelin' your jeep.

Especially if it is a 96+:)

[urbanXJ]

Woods shaft/AA SYE kit all the way. Worth every penny, best money spent on XJ yet. Not to hard to install. I mulled around with it myself for far to long.

NAXJA members get 25$ off.
RE 3.5 lift w/ full packs gave me 35 and 7/8 working length (me anyway). No more vibes, only an "oscillating drone".

[Eagle]

Been holding off on this thread but I guess it is time to jump in. I have a 2000 Sport with 5-speed and Up Country. The vibes are terrible. It isn't undriveable, but I know that every foot I drive it I am taking life out of the transfer case bearings. I have a JB Conversions SYE waiting to go in, but can't do it until I scare up the funds for a new driveshaft.

The new "improved" driveshaft design came out in 1996. IMHO, if you have a '96 or newer XJ you should automatically budget for an SYE before even considering a lift of any height.

[Talyn]

Originally posted by Eagle
Been holding off on this thread but I guess it is time to jump in. I have a 2000 Sport with 5-speed and Up Country. The vibes are terrible. It isn't undriveable, but I know that every foot I drive it I am taking life out of the transfer case bearings. I have a JB Conversions SYE waiting to go in, but can't do it until I scare up the funds for a new driveshaft.

The new "improved" driveshaft design came out in 1996. IMHO, if you have a '96 or newer XJ you should automatically budget for an SYE before even considering a lift of any height.

You don't have a true lift, but have a stock Up Country suspension and it vibe swith just that?

-Chris

[Kejtar]

Chris, I know of at least one instance where the dealer ended up installing an SYE (at no charge) for someone because the driveshaft replacement and transfer case drop didn't fix the vibes. I believe it was on a 1999 Cherokee. If you did hard enough on Google you should find it, so the fact that Eagle's Sport vibed is no suprise to me. I don't know how bad is his "terrible" but it's no surprise that it vibes :(

[Amund2]

Hmm, not meaning to ruin the fun here, but I've bought Old Man Emu and I'm wondering if I did something amazingly stupid. First about the polyurethane bushings - they came with the set, but I don't know why. I can see the point of stiff bushings in an asphalt racer, but absolutely not in an offroader, and not in a set of springs that are supposed to be comfortable. First, leaf springs twist sideways when flexing, soft rubber bushings would help. Stiff poly bushings would ruin a lot, both in flex and comfort.

Second, about spring rates. The shop I bought the kit from told me that I need A springs on the driver's side, B springs on the passenger side. I immediately thought of Australia, and how their drivers are on the "wrong" side. The shopsman claimed the springs followed the driver, and were supposed to compensate for his weight. Well, what if I have a passenger?

As I suspected, all my springs are on the wrong side, and the car leans to the right. Additionally it leans forward, being much taller in the rear. It is also a lot stiffer behind. When I bought the set I asked for front springs for a 2,5 litre, but they said there were just one type of springs. Now I've got a 4,0, and it's a lot softer and lower in front. Very annoying, both in bumps and off road, where the car flexes nicely up front, but when the rear wheels reach an obstacle the car doesn't flex but rather tilts with whatever terrain is under the rear.

To top it all off, all other kits seem to offer a lot more parts for the same price, and also scoring better in tests. But I'll have to say that this issue isn't finished yet, I've talked to the dealer and they have been very understanding, we've been in contact with ARB Australia and everyone's determined to make me pleased. So we'll see what happens.

[Amund2]

But I forgot to mention my main point regarding this thread: The only problem I haven't had is vibrations! :cool:

[Kejtar]

Hmm I haven't heard of springs being side depndant on any of the commonly available kits... In regards to the front sitting low, slap some coil spacers up there and you'll be good.

In regards to the vibes and lack of, which year do you have? which tcase and tranny and which rear end? ALso look at the output from the t-case. I wouldn't be surprised if you had a factory SYE or something like that :D

Kejtar

[BLUTO]

I also had read that OME has "compensated" their springs to fit on the driver's side. So I called ARB, because my coils were marked "LH" & "RH"(Austrailian drivers-RH or American passenger-RH?). The rep said to install the taller coil on MY drivers side. It still sits 3/16" higher on passenger side :confused: ....I'll give them time to settle ;)
The TC drop is a cheap way to help get rid of vibes, BUT does it relieve stress on the TC bearing and shaft? AND....since you're changing the angle to the rear axle, you are also changing the angle to the front axle too,....doesn't this cause stress on the front output shaft, bearings, and driveshaft components? :confused: It just seems like there's no free lunch here...robbin' from Peter to pay Paul. For longevity, maybe I should leave the TC where it is, no shims, save up a few bucks and go right for the SYE!? Gears, diff's, and bumpers can wait :(

BLUTO :)

[climbon]

Hey Bluto, SYE and CV driveshaft will take care of it. I had the same problem with my old 3" lift at about the same speed. Spent the extra $ and it was gone. Go see the guys at Mepco and they will take care of you. See you on the next trail run.

[pperelman]

I have 98 with 6" of lift, SYE rear 8.25 and it vibates at approx 60MPH regardless on or off throttle or loaded or not!!!
I dont know what it is....If all goes right I soon get D44

[Amund2]

Originally posted by Kejtar
Hmm I haven't heard of springs being side depndant on any of the commonly available kits... In regards to the front sitting low, slap some coil spacers up there and you'll be good.

In regards to the vibes and lack of, which year do you have? which tcase and tranny and which rear end? ALso look at the output from the t-case. I wouldn't be surprised if you had a factory SYE or something like that :D

Kejtar

Coil spacers would fix the height, but not the fact that the front springs are much softer than the rear!

Mine is a 1986. But I have a 1993 ZJ drivetrain, with AW4 & NP231. Standard slip yoke.

[Talyn]

Originally posted by pperelman
I have 98 with 6" of lift, SYE rear 8.25 and it vibates at approx 60MPH regardless on or off throttle or loaded or not!!!
I dont know what it is....If all goes right I soon get D44

Sounds like a not balanced driveshaft.

-Chris

[DMMcG]

Originally posted by Amund2
Hmm, not meaning to ruin the fun here, but I've bought Old Man Emu and I'm wondering if I did something amazingly stupid.
Second, about spring rates. The shop I bought the kit from told me that I need A springs on the driver's side, B springs on the passenger side. I immediately thought of Australia, and how their drivers are on the "wrong" side. The shopsman claimed the springs followed the driver, and were supposed to compensate for his weight. Well, what if I have a passenger?



Amazingly stupid....but just in an ignorant kind of way - sounds like you "shop" had some spare parts to get rid of.

The JC1A has an extra inch of height over the JC1B. Using them together doesn't make sense. The front coils are of marginally different heights, with the longer one going on the driver's side - frankly, the difference in height is so nominal that even if you mix them up it's not significant.

Buying OME springs hardly constitutes a "kit". You're buying springs and shocks. You still have to address the other suspension issues yourself, if you choose to go higher than the 2" OME JC1B/930 combination. With the basic JC1B/930 springs and N35/36 shocks you don't "need" to change anything else - just straighten the front brake hard-lines and re-attach them lower on the uni-body as they get a bit tight when your anti-sway bar is disconnected.

It's a shame that your "shop" has left you with a bad taste for a great product. Hope that they fix things for you without too much more grief.

You should be able to achieve an RTI in the high 800's/low 900's on a 20° ramp with the basic OME suspension (depending on air pressure/tires-wheels & ramp placement).

http://www.hot4x4.ca/albums/album20/aaa.thumb.jpg

[Amund2]

Yep, it flexes just fine. But the documentation that followed the springs (a whole lot of it actually, a lot from OME, and a bunch from TÜV) says to put the A springs on the drivers side, and the B springs on the passenger. It doesn't say why, but it does say that you have to test fit it, and that you probably have to change it afterwards and so on. Seems very inaccurate, these springs.

Another thing that annoys me in the afterhand is that these springs with shocks cost as much as most other kits, which come with more stuff like control arms and such. I would expect this to be extremely excellent when it's this expensive! But no, seems I've been had. We'll see what happens with it, maybe the shop will give me something for free to make me happy.