OK ,I have a 2002 jeep wrangler with a 2.5" rough country lift,4.0 , automatic trans,the jeep runs out fine ,shifts smooth and on time every time,the problem is vibration, runing down the road while excelerating i get a vibration .let of the gas it stops ,give it gas it vibrates as long as it's under a load .take foot of gas it stops,put jeep in nutrial give gas no vibrtion,put in drive give gas starts to vibrate ,does not make noise ,got wheels /tires balanced did not help, could this be a drive shaft or trans problem or a rubbing or a stress problem some where ,the trans shifts varry smooth and guit,its not a bad vibration but its there . could this be from the lift ,some binding or mis alinement issue or what . any info will be thankfull.
2002 wrangler 2.5 lift vibration problem??'s
- Thread starter dennyray
- Start date
Saddle Tramp
New member
Did you install a transmission lowering kit at the skid plate? If not vibration will be a problem. Your next option is to install a slip yoke elimination on the transfer case.
Bounty__Hunter
Super Moderator
Generally don't need to lower the transfer case skidplate with a 2.5" lift.
Was anything done to correct the caster in the front end? Most complete lift kits include longer lower control arms to correct the caster. If nothing has been done, you will need to buy a pair of adjustable cam bolts for the axle end of the front lower control arms. Adjust the cam bolts so the bottom of the front axle is pushed as far forward as possible. This will correct your caster and pinion angle. Your vibe is likely coming from improper pinion angle in the front.
Adjustable cam bolts run about $30-$40. They came from the factory on early TJ's but not the 2002.
Was anything done to correct the caster in the front end? Most complete lift kits include longer lower control arms to correct the caster. If nothing has been done, you will need to buy a pair of adjustable cam bolts for the axle end of the front lower control arms. Adjust the cam bolts so the bottom of the front axle is pushed as far forward as possible. This will correct your caster and pinion angle. Your vibe is likely coming from improper pinion angle in the front.
Adjustable cam bolts run about $30-$40. They came from the factory on early TJ's but not the 2002.
The Rough Country 2.5" kit is just shocks and springs:
Jeep TJ Suspension Lift
I installed the same kit and didn't get any vibrations (but every Jeep is different). I did need to fix the caster (I went with new lower control arms - the same outcome as caster bolts, but more expensive).
Keep in mind that Jeepz.com members get a 10% discount at Rough Country
http://www.jeepz.com/forum/4x4-vendors/27627-rough-country-here.html
Jeep TJ Suspension Lift
I installed the same kit and didn't get any vibrations (but every Jeep is different). I did need to fix the caster (I went with new lower control arms - the same outcome as caster bolts, but more expensive).
Keep in mind that Jeepz.com members get a 10% discount at Rough Country
http://www.jeepz.com/forum/4x4-vendors/27627-rough-country-here.html
I was reading the install directions for RC's long arm kit and saw this:
Bounty__Hunter
Super Moderator
The fact the vibe changes on and off the gas leads me to believe it's a rear driveline angle problem, most easily fixed with a 1/2" transfer case drop.
I'd still correct the front caster with the cam bolts which also corrects the front pinion angle.
I'd still correct the front caster with the cam bolts which also corrects the front pinion angle.
Ok,changed out all u joints,front and rear,also changed out front end componets such as the sway bar links,tie rod ends ,installed a new steering stablizer,vibration is still there,i will order a transfer lowering kit,but first i have a guestion,i have the 2.5 lift and ordered a new set of coil spring perches or pads as some call them there 3/4 " will this efect the ride any ,will i need to get the lowering kit for a 2-2.5 lift or get the one for a 2.5 to 4 " lift ,i called rough country and they were no help at all .the person i talked with new nothing .thanks again
Bounty__Hunter
Super Moderator
Where will the 3/4" spacers be installed?
You can easily fab something 1/2" thick to space the belly pan away from the frame, may need 6 longer bolts.
You can easily fab something 1/2" thick to space the belly pan away from the frame, may need 6 longer bolts.
mattduran
New member
Hi. Sounds like something sure is off here. Are you much of an off roader? I only ask cause you may have tweaked something like the rear drive shaft. Sounds like u joints but already replaced you said. Common to get those vibrations when accelerating with bad u joints or bent drive shaft. This small of a lift should give you issues that your speaking of. Good luck
Bounty__Hunter
Super Moderator
It will pull the axle off-center slightly but not enough to cause the vibes described.
OK.the 3/4" spacers is for the springs to set or ride on front and rear,will the jeep still set level as well.No not much of an off roader just like mud ridden in open fields and dirt roads nothing extream,just bought the jeep working the bugs out ,driving me crazy.i'm trying the less expensive fixes first ,i fabracicated the spacers out off one inch stock ,i'll try this if i can locate longer bolts,i think i'm just going to run the 33x12.50 x 15 nitto trail grapplers on a 10x15 wheel ,it's a daily driver 50 miles round trip daily don't need nothing to crazzy ,my 16 year old daughter will be driving it as well,She won'ts to build a small block this summer and add a new lift and run 38's that's my girl .project in the making.that's what i'm talking about...... thanks to all .let me know on the spring spacer thangy.will that give me an extra 3/4 " of lift as well .
