wobbly at 50-55, yes I've searched

I've done the leg work searching but can't decide where to start. Here's whats up:
I've had a shimmy around 50-55 MPH for months. I assumed my old, worn 30x9.5" tires were out of balance. Today, I changed all 4 tires to some used 31x10.5" tires with 8 oz of airsoft BBs in them.
Same old small driveline vibe at 30 or so. Smooth to ~50, when the same old vibe / shimmy is now showing up as a shimmy / wobble. In other words, it got worse.
So, I've got two lines of thinking here.
One: airsoft BBs don't work very well. This leaves the mystery of why ~50 mph, though.
Two: I had a slight shimmy coming from somewhere else in the front end and the steering stabilizer (OEM, over 100K miles) could disguise it with the 9.5" wide tires, but having a harder time with the 10.5" tires I have now.

I'm leaning towards theory #2 but don't know where to start looking. Could a worn track bar show up at such a narrow range of speed?

this is called death wobble... theres 23489235348790812089234098234 places online that could help you with it. there is alot of different problems that could cause it.

worn track bar bushings, lower control arms wrong length causing a bad driveline angle, you might need a SYE or TC drop kit, check your alignment, bad shocks, incorrect tire pressure. steering stablizer might be worn out. the list continues...

MaxxXJ said:

this is called death wobble... theres 23489235348790812089234098234 places online that could help you with it. there is alot of different problems that could cause it.

worn track bar bushings, lower control arms wrong length causing a bad driveline angle, you might need a SYE or TC drop kit, check your alignment, bad shocks, incorrect tire pressure. steering stablizer might be worn out. the list continues...

Click to expand...

X-2 :banghead:

I was really hoping for a different answer but yeah, I'll start running through it all in the usual fashion. Thanks!

mine was doing the same thing with 32 swampers. It was my drag link. I changed the end by the pitman arm and all better. steering stabilizer wont hide that either.

Just search death wobble. Make sure alignment is good, make sure tires are actually balanced...throwing some airsoft bbs in there isn't necessarily the most exact way of doing it. Crawl underneath, find any possible loose bits in the steering.

Your condition really isnt the dreaded death wobble. You have a shimmy which can be caused by some of the same things that cause death wobble and as mentioned need to be checked. Get rid of the air soft and have the tires balanced on a Road Force machine and use wheel weights. Death wobble is when at speed you hit a bump and the front end violently shakes back and forth almost uncontrolably and can cause loss of control and in extreme cases...........well, death. Although I ve never heard of anyone accualy being killed, but trust me when you excperience it, you think you are going to die.

this is not death wobble. death wobble is a shit-your-pants, how-did-i-not-hit-the-guardrail situation. you know it when it happens.

airsoft bb's could make it worse if you have the wrong amount in or something... airsoft bb's are a bandaid (and so is a steering stab), not a definite way of balancing.

you said you searched; did you see anything about checking for worn or loose parts? (ball joints, tie rod ends, control arm bushings/joints?) any of those being loose or worn could cause a shimmy. are you 100% sure it's the front end and not a driveline vibe? 50-55mph is telltale for driveline vibes... make sure your track bar joint is tight as well as it being tight to the axle.

OK, def not death wobble, my shorts are still clean.
Got tires to correct pressure (tire shop left all 4 uneven but in the ballpark of 40 lbs!) and it helped, think I'll go elsewhere and balance them the regular way and see if it cures.

Track bar joint moves vertically in the bracket when the wheel is turned in park. Thinking that even if this is unrelated to my shimmy, needs replaced.
Thanks for help, really clears up my thinking.

MaxxXJ said:

this is called death wobble... theres 23489235348790812089234098234 places online that could help you with it. there is alot of different problems that could cause it.

worn track bar bushings, lower control arms wrong length causing a bad driveline angle, you might need a SYE or TC drop kit, check your alignment, bad shocks, incorrect tire pressure. steering stablizer might be worn out. the list continues...

Click to expand...

Not death wobble, and an SYE or TC drop kit is not gonna fix death wobble. Might fix his issue but I doubt it, since he describes it as a front end shimmy not a driveline vibration.

jeepme said:

Your condition really isnt the dreaded death wobble. You have a shimmy which can be caused by some of the same things that cause death wobble and as mentioned need to be checked. Get rid of the air soft and have the tires balanced on a Road Force machine and use wheel weights. Death wobble is when at speed you hit a bump and the front end violently shakes back and forth almost uncontrolably and can cause loss of control and in extreme cases...........well, death. Although I ve never heard of anyone accualy being killed, but trust me when you excperience it, you think you are going to die.

Click to expand...

I know of someone who nearly got killed by it - the guy who built that Toy pickup with the XJ front end (search for the xota project.) He got death wobble on the way somewhere, it broke the wishbone link in his front suspension in half, axle went back under the vehicle and he stuffed it into a guardrail. Could have been much, much worse.

It isn't death wobble till things are flying out of your cupholders and you have to readjust the mirrors afterwards. That's when you know you actually got death wobble, till then it's just tire shimmy.

EDIT: http://www.naxja.net/forum/showthread.php?t=69712&page=23#343 is where he describes what happened, pictures at http://www.naxja.net/forum/showthread.php?t=69712&page=23#336, start of thread http://www.naxja.net/forum/showthread.php?t=69712

yossarian19 said:

Track bar joint moves vertically in the bracket when the wheel is turned in park. Thinking that even if this is unrelated to my shimmy, needs replaced.
Thanks for help, really clears up my thinking.

Click to expand...

loose trackbar is definitly related to a shimmy.

i had a deathwobble that went away when i replaced the 215k miles steering stabilizer. mine suddenly would thrash violently when i hit about 50 sometimes