I've got a shimmy/vibration in my steering wheel when driving between 40-50 mph. I had the wheels balanced and a wheel alignment done. Still I get the shimmy. Assumming that the wheels were balanced properly, would the only other area that could be suspect be the steering linkage (tie rod ends, etc). This truck has about 105K on it.

Replace the steering wheel.

I bet it's the shimmy shock.

I wondered if it was possibly the steering damper. That thing has been leaking oil for a while now <img src="/forums/images/graemlins/rolleyes.gif" alt="" />. Sure wouldn't hurt to replace it

shimmy shock? is this sarcasm, or is this a real part? i too have had this. it came out when i had my tires changed. come to find out, i had one tweaked rim, and one "almost" tweaked rim...haha.. i know. the second one was not bad enough to replace, but the little vibration is too annoying now. time for 4 new wheels.

I had both tie rod ends shot. It was pretty serious, no alignment or diff. tires could stop it. Most likely that's your problem too, the faster I went, the less I felt it. Mostly when driving straight. There is so much play now that the tires just go wherever they want until the play restricts it. You might not be able to just jank on the tire and think you'll know. The local tire store put my car up on the lift and had a movable plate that was air actuated under both front tires. It moved rapidly from side to side. That's when you can see the real play.

Shimmy shock = steering stabilizer

Just a nickname... <img src="/forums/images/graemlins/cheers.gif" alt="" />

Where did you get the Tires balanced and wheel alignment done? They should have checked for any slop in the steering system. Most steering shimmy comes from tires. Rotate the tires and see what happens. I don't even use a steering stabilizer on my '85. If everything is tight you don't really need them. It just make them harder to steer in my opinion.

<img src="/forums/images/graemlins/cheers.gif" alt="" />

keep the shimmy shock. If you hit a pothole or nice rock, the steering wheel will want to turn really quick..depending on what side of the front tire hits it. If you dont have a firm grib, you will be sorry for taking it off, I say keep it... My Nova had a bad vib up front going about 40mph...I had to replace the tie rods ends. They were worn real bad. If you get to sit in on the next time they balance your tires...look at the tread surface while it is spinning(High speed balance). One tire up front on my toy had a lump on it. That was the problem I had on a vib up front at higher speeds. Jack up your truck and place a jack under the frame. Spin Tire with your hand and see if they are nice and round. while the truck is up. See if you can get a friend to wiggle the tire vertically and horizontaly while you look at the tie rods, pitman arm, ball joints, etc. On your shimmy shock after removing the side where the small shaft is connected to. pull and push it in and out. If you can do that without much or little effort it is toast...replace it. Just a few Ideas that I would say to check over.

First off have your tires rebalanced. That is the major cause of shimmy. Second jack up the front end ( both tires at once)and shake each tire side to side by hand and check tie rod ends, pitman arm and idler arm ends for excessive play. The alignment shop should have already checked for this. If theres play, replace the faulty part. Replacing the steering stabilizer will have no effect on reducing the shimmy.