Too easy steering is a sign of too little positive caster which is one of the three main alignment angles. If you look at the fork of a bicycle, you'll see it's angled rearward at the top. Putting weight on it is what allows you to ride no-handed. It makes the front wheel squirt out to straight ahead.
On your truck, caster is the same angle formed by the orientation of the upper and lower ball joints. Positive caster means the upper ball joint is to the rear of the lower one. Before the mid 1960's, a lot of vehicles had negative caster. That made for real easy steering on heavy cars and trucks, but it greatly increases steering wander. By the mid 1960's when people started driving faster, that wander became a problem. We went to positive caster to increase stability, but then we added power steering to overcome the increased steering effort.
The place to start is by having the alignment checked. Caster should be set to somewhere around 3.0 degrees, and possibly a little more. You have to be careful about going too high on GM trucks though. Caster is also what gives us the steering wheel return to center after going around a corner. If caster is too high, the steering system will return to center with so much force it will overshoot and go the other way, then back again. That is commonly referred to as the "death wobble" because you're sure you're about to die. The shaking can be real severe. Someone may have previously tried to correct that condition by lowering caster. You need positive caster for stability and road feel, (sufficiently-hard steering effort), but if that over-shoot becomes a problem, consider adding a steering stabilizer. They're made for this purpose. The part looks like a shock absorber that lays on its side between the frame and steering linkage, but unlike a shock absorber, these retract and extend with equal force in either direction,
If the alignment is okay, there could be a problem with the reaction shaft in the steering gear box. That is not real common and is more likely to result after someone had it apart to try to fix something.
Monday, March 14th, 2016 AT 3:15 PM