bad 5mph shimmy?

related specs:
3" rough country
265/75 bfg all terrains (~ 15k on them)
pro comps
spidertrax , front only

Had balancing issues before, took it in the Discount to get re balanced/rotated after a few months. Has a shimmy around 55mph, but esp bad around 5mph. Almost like the wheels are about to come off. Been driving me insane, maybe they did a sh*t balance job? Rears are now on front with some typical bfg tread eaten up but not bad enough to compensate my ride comfort, maybe thats it ? All lugs/ spacers are torqued, inflated and tight. Need some input so I can figure what to pursue to fix the problem. Thanks in advance

 

did they roadforce balance the tires?

 

just machine balanced as far as i know

 

maybe call around and see if one of the tire places has a road force machine. could make a big difference for you.

 

Hopefully they do, Id rather not have to pay twice for balance that they should have done right the first time . Maybe Im just frustrated, but I guess thats what I get for having Discount Tire do it with the plethora of dumbass high school kids they all seem to employ. gah

 

If the shimmy is present at 5 and 55, it is likely that something is bent.... Balacing is not a factor at 5 mph.
Unless, you are gettting the common 5 mph U-joint vibes, and then a secondary issue at 55 mph.

 

Just left the tire shop, checked the balance, says everything is good on them. Tried to rationalize in my head what it could be, thought maybe the rotors warped but i dont have much braking issues besides them being a bit soft (even after pads and fluid change). What U-joint vibe is there? Never heard of that issue before. What should I check for?

 

Kinda like you described, a slight shimmy related to driveline (driveshaft) angles. Basically, you need to identify where the vibes are coming from, there is lots of info on the net on locating vibrations on vehicles, google it.

 

bump. searched with too broad of results with nothing that answers my problem unfortunately. Any suggestions on what to narrow it down to? drove it around some more 0-10 mph for a few blocks and it more of a side to side rocking motion more than a vibration.

-Driveshaft back is fine, nothing leaking,broken, loose, etc.
-Wheels/tires balanced, no flat spots, inflated.
-Spidertrax still torqued to spec, loctite.
-brakes are new, rotors not warped.
-tranny mounts are fine

 

what should I look for that might be bent?
Took the wheel spacers off today and drove around thinking it might have been that and naturally the shimmy was still there.

 

BFG AT's are very difficult to balence I used to get the return customers all the time since they are a royal pain to balence correctly.

 

The redneck test for driveline angle problems: Put a bunch of weight in your truck bed, a few hundred pounds at least to 'lower' your rear end and thus lower your driveline angle, IF the vibes go away then your looking at an easy fix: shims or carrier bearing drop or both.

If the problem still occurs after the red-neck test then at least you can check 'driveline angle' off your list.

Also, do you feel the vibes in your seat or the steering wheel more?

Can you post your alignment numbers? they should be in your paper work from your alignment.

Also, a while back I had a balancing issue, I thought it was my spidertraxx spacers but it turned out to be a poorly balanced tire... regardless, at one point I contacted Spidertraxx to have my spacers tested/replaced... within 12 hours they got back to me with a shipping label to return them and where very accomdating... so if you feel the spacers are to blame they will help you out, luckily mine weren't but you never know.