In my 84 z28, when driving around town at low speeds the steering is tight and smooth. But when i get up to highways speeds i have to hold the steering wheel at the 10 oclock position in order to keep going straight and i get a small amount of vibration. I bought the car about 4 years ago and never had this problem until the start of this summer. Tie rods, ball joints, idler and pitman arm look in good condition so im thinking it's either the rag joint or steering box. Anyone have any advice, i'd really appreciate it.

 

It's usually the steering box, but a astro shaft steering shaft upgrade can help a bit.

You can grab the bottom of the steering shaft with a vice grip and have someone turn the wheel and feel the play by hand. Probably some but not much there.

You can then see the play in the steering box by turning the steering wheel side to side, and any amount that the steering shaft turns but the wheels dont.. that's slop in the steering box.

Lares does a nice reman on steering boxes. You can even send your box in to them to have remaned.

 

1. Rebuild linkage
2. Install Astro shaft
3. Get a professionally built steering box
4. Use the proper alignment specs, not the factory garbage.

 

10:00 I'm going to assume means you have to turn it to the left about 60°?

And you have a vibe? Tire vibe I'm going to guess?

A separated tire can cause both of those symptoms. Try swapping your front tires side to side. If you suddenly have to hold the wheel at 2:00, you just found your problem; and it isn't the steering.

I'm also going to assume (yeah I know, but it's all I can do at the moment) that you already had your assistant sit in the car and shake the wheel side to side while you got up under it and looked for play and lost motion. That of course, being the VERY FIRST THING any sensible person would do when … looking for play and lost motion. And furthermore that everything is all tight and that whenever the upper steering shaft reversed its turning direction that the tires immediately started turning, and nothing moved inside of anything else or anything like that.

 

your video (I think) has an error in it. I asked you a while back about it, but never heard back. was trying to get some clarification. forget what it was. check your original post for my question.

 

I listed the wrong part number for the idler arm.
The correct one is the AC Delco.
Moog idler=junk