Is it normal for the steering to wander at speeds over 50 MPH? When I drive at low speeds it seems to handle OK, but when I speed up to over approx 50 MPH my steering gets a little loose, and begins to wander. It's not so bad that I can't keep it under control; its more like driving on a really windy day. Should I suspect steering components, or is it just an old truck and not really engineered to be driven at highway speeds?
There could be any number of causes, but the first things I'd check would be: 1. Equal and correct tire pressure. 2. Bad idler arm. If the idler arm is shot, the left tire wants to follow the steering box/pitman arm, but the passenger side tire develops a mind of its own when the idler arm cannot maintain the steering linkage in alignment. 3. Too much toe out. Almost the same problem as a bad idler arm. At slow speeds the front tires are pretty much pointing straight ahead. If there is too much toe out, or if the system "toes out" due to worn steering linkage components, the wheels no longer point straight ahead. One is pointing to the front while the other turns to the outside. When that wheel is corrected by moving the steering wheel, the other side turns outboard. The vehicle will have a tendency to dart back and forth and become worse the faster the speed. 4. Bad, broken or worn out shock on either side (or both), or a broken mount. 63-66 frames have a tendency to oval out the upper shock mounting hole. If one of the shocks isn't functioning correctly, the tire on that side will tend to bounce up and down throwing the steering off. 5. If the tires were correctly balanced, it is possible one of the wheel weights came loose and was thrown off. If the resulting imbalance is bad enough, it can shake the steering. These are all things you can check yourself before spending money at a shop for diagnostic time.
It did get worse after I increased the tire pressure to 32psi (it seemed low at 24psi). I'll check the shocks etc first, but the tires have not been balanced or aligned since I have had the truck, that probably needs to be done anyway.
