Front suspension shimmy

[Fairlaniac]

My ’91 4x4 Ranger has developed a vibration which I think is suspension oriented? So I’m looking for some direction. it has 235/70/15 tires. It feels like it’s in the front. It sometimes feels like the front tires are oval however they appear to not have any issue when you spin them or when I rolled them on the ground, off the truck. I did move the rear tires to the front and still the same issue. It happens above 45 MPH and will continue up through 70 mph. Sometimes it kind of goes away so it’s not happening all of the time. I replaced and properly set new front wheel bearings. New seals and pads while apart. There is no movement indicating bad ball joints. I grab the top and bottom of the tire and try to rock it, no movement. Ball joints don’t seem too bad but I have bought new ones but not yet installed. There is some rattling from the radius arm bushing area so I bought a new kit, not installed. Nothing seems to be really shot except the radius arm bushings. I don’t just want to keep throwing new parts at is as the previous owner did keep up with most wear items. I don’t see any excessive wear or patterns on the tires either. Going down the highway it shimmies like hell on the front but the feedback does not come back through the steering wheel. The wheel is steady and straight. I really feel it in my gut. I usually have an OJ while driving to work. By the time I get there my stomach feels like an Orange Julius.

Any ideas or help is appreciated.
Thanks,

 

[martin]

Did you check the driveshaft?

 

[PanamaExpat]

Swap the rear tires with the front and see if it moves.

 

[4.0B2]

get under it and watch the steering and stuff...have someone sit inside it and wiggle the steering wheel back and forth... look for stuff that doesn't look right.

tire rotation, grab your drag link and stuff and wiggle it, does it move? same with your radius arms...

 

[Surrey]

If rad arm bushings are shot, start with replacing them.

They are what keeps your axle in place, so if they are shot it has room to move forward-and-backward, which I would think could create some very unhappy characteristics.

 

[alwaysFlOoReD]

All the above are good suggestions, some you've already looked but it doesn't hurt to double check.
Missing wheel weights?
Driveshaft bent or missing weights?
U-joints?
Tire that is round but has separated?....look at the tread depth and make sure it is even depth all around the tire.

Richard

 

[Fairlaniac]

Swap the rear tires with the front and see if it moves.

Done that!

 

[straycat]

How old are the tires? When were they last rotated and balanced by a shop? It could be a number of things to tell you the truth and you should just take it to a shop you know and have them check it out for you instead of waiting for an internet reply/fix, Bro. You already have done some work to it and that is not the issue with the shimmy. The shop can check your drive shafts as well while the truck is up in the air and they may see something you might not see and save you some money...or better...YOUR LIFE!!!

 

[bigtruck94]

The more you leave it, the more likely your gonna have your front end fall apart on you driving down the highway. Replace your ball joints, U-joints, look at the upper and lower driveshaft and see if there is any damage. Radius bushings are more likely need to be replaced too.

 

[Fairlaniac]

Center support bearing

Ripped out the center support bearing. New one and u-joints on the way from RockAuto.

Thanks!