WHY THE WIGGLE?

CAN ANYONE TELL ME WHY THE TRUCK WIGGLES WHEN I FIRST TAKE OFF NO MATTER HOW FAST OR SLOW I GO? ALSO, MOST OF THE TIME WHEN COMING TO A COMPLETE STOP I FEEL A BOOM COMING FROM THE BACK AND THEN THE ASS END KINDA SORTA DROPS DOWN...THEN WHEN I GOTO TAKE OFF IT BOOMS AGAIN. IT FEELS LIKE SOME KINDA SLACK IN THE DRIVELINE....I HAVE TO LET IT ROLL A LITTLE BIT BEFORE I HIT THE GAS OR IT FEELS LIKE IM GONNA BLOW THE REAR, BUT I DONT KNOW IF THATS WHATS CAUSING IT FOR SURE....ANY HELP WOULD BE APPRECIATED!

Sounds like a broke tranny mount and maybe ujoints...

Cory

DUDE: DO NOT TYPE LIKE THIS. Whoa... that's hard to read and considered "yelling" to some people.

That back channel response was unacceptable, watch your step.

I wasnt yelling by the way....Im not really "hip" to proper chatroom ways, Im just tryin to find out whats up with my jeep....I thought it was the tranny mount too but it wasnt. One of my boys is a Jeep mechanic and hes never seen a jeep do this....you know its bad then . It really dives to the right under quick braking (like how fast you hit them) but its got all new shocks. Keep in mind this is a 2000 w/172k on it all highway (until 3 mos ago when I bought it off my sis) no bodywork of any kind ever done.

himold said:

It really dives to the right under quick braking (like how fast you hit them) but its got all new shocks.

Click to expand...

Totally unrelated. Look at the BRAKES (rotors, caliper, pas, etc) as a source of that problem, and not the shocks.

It's not unusual for the slipjoint in the rear driveline to bind up slightly when coming to a quick (nose-diving) stop - that's the nature of the rear springs and front coils transferring the vehicle weight. Try making sure the slipyoke is lubed slightly to avoid some of the BANG that it makes otherwise.

As for the 'wiggle' - more info is needed about where it's coming from, what equipment you have and what exactly it's doing.

The only way to describe it is a "wiggle". The truck actually wiggles upon immediate takeoff for 1 second as soon as power is applied in any amount. It does it so hard everytime my body actually wiggles with it.

Oh and its def not the brakes....they were all replaced....all of the obvious has been tried people, Im not stupid.

Are the front control arm bushings in good shape? May not be the problem, but it could contribute to it.

The folks Dodge Caravand shimmys on take off, up unitl 10 mph. Must be a Mopar thing.

Maybe ask over on the JU board too.

Yeah Im thinkin its the control arms but the bushings arent that bad, so I will get new ones with my lift I guess

My '95 used to do that wiggle thing, never thought to much about it, thought maybe it had a bent wheel, never did find out what it was.

Its probably a bent rim or axle shaft. Could be more then one wheel!
The bang noise could be your slip yoke sticking. Pull drive shaft and add grease to splines. Also check ujoints for play.

have someone get in and put it in drive then reverse while holding the brakes as you watch the rear axle, watch for excessive rotation of the axle, old and weak springs could be allowing excessive axlewrap or if you have lift blocks this could be the cause

as for diving to the right upon braking, go down a gravel road and apply the brakes, take note of one side grabbing more than the other, I know you said you changed the brakes, but did you change the calipers? Mine was doing this earlier this week, and a trip to a friends house revealed that my front right caliper was hanging, not overtly noticable when working on it, it seemed to move normally when off the vehicle, but a $20 caliper and brake bleeding later the problem is gone.

now for the wobble. XJ's are prone to wobble, any little bent anything in the front end and the feeling is exacerbated by the springiness of the unibody and lack of rubber isolation between a frame and body. Speed specific wobbles can be attributed to wheel balance and/or rims being bent, most wobbles induced when hitting bumps or when turning can be traced to CA bushings, worn steering stabilizer (just a patch to cover up any real problems until they get serious), worn trac bar bushings or TRE's

good luck

Have checked you 3 member? Maybe the c-clip fell out and you are binding the axel.

Bo

I had a couple vehicles wiggle on acceleration from stop or on the road, and in each case I had a broken or worn out motor mount. I also had one case of the rear axle rotating up & down do to loose U bolts. That one lurched around & made a lot of banging noise. My 2C.