It’s at the alignment shop now...I’ll let you guys know in a couple hours what goes on.
CK5
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Over boosted power steering
- Thread starter mark84k5
- Start date
It might very well be none of the above. I have seen this once before.
There is a small leaf spring inside the power steering box that keeps the valve centered. When you start to turn the wheel, the force pushes on the valve to move the output shaft of the box.
Of course, it hits resistance. As you continue to turn the steering wheel, the spring bends allowing the spool valve to move sending pressure to assist the turn. As the output arm moves, the spool valve recenters. If you continue to turn the steering wheel, the spool valve continues to allow boost until you stop turning the wheel.
What you feel when you turn the wheel, is the spring tension inside the box. Custom box builders can change the strength of that spring to give you more or less "feel".
On a company truck I was driving, apparently that spring broke. I got in it, and it was like driving a video game. All you could feel was the friction of the ball bearings in the steering column.
I loved it. It drove great, but the steering wheel would not return to center, so you had to steer it both ways. Also, if you were up against a curb, you could damage your tie rods or things, because you had no feedback as to how hard you were turning the wheels.
Unfortunately, I was not the only one driving it, and a couple of the other drivers freaked out. So the shop put on a new steering box and it went back to normal.
Way later, I saw a magazine article, (remember them?) that told of a company out west somewhere that build custom steering boxes. They had a selection of springs that they could install to give you the amount of road feel you wanted. From video game to manual steering.
I always wanted a super light box, but never got one, and have no idea what that company was at this late date.
There is a small leaf spring inside the power steering box that keeps the valve centered. When you start to turn the wheel, the force pushes on the valve to move the output shaft of the box.
Of course, it hits resistance. As you continue to turn the steering wheel, the spring bends allowing the spool valve to move sending pressure to assist the turn. As the output arm moves, the spool valve recenters. If you continue to turn the steering wheel, the spool valve continues to allow boost until you stop turning the wheel.
What you feel when you turn the wheel, is the spring tension inside the box. Custom box builders can change the strength of that spring to give you more or less "feel".
On a company truck I was driving, apparently that spring broke. I got in it, and it was like driving a video game. All you could feel was the friction of the ball bearings in the steering column.
I loved it. It drove great, but the steering wheel would not return to center, so you had to steer it both ways. Also, if you were up against a curb, you could damage your tie rods or things, because you had no feedback as to how hard you were turning the wheels.
Unfortunately, I was not the only one driving it, and a couple of the other drivers freaked out. So the shop put on a new steering box and it went back to normal.
Way later, I saw a magazine article, (remember them?) that told of a company out west somewhere that build custom steering boxes. They had a selection of springs that they could install to give you the amount of road feel you wanted. From video game to manual steering.
I always wanted a super light box, but never got one, and have no idea what that company was at this late date.
An addendum to my earlier reply. The box I was driving, back in 1976, claimed to use a leaf spring to keep the valve centered.
But I'm not sure it was a Saginaw box.
It seems those use a torsion bar as a spring. The stronger the bar, the harder you have to turn the wheel before the boost kicks in and thus determines your road feel.
Since the weaker the bar, the less you feel, makes me think your torsion bar has come loose or broken inside the box.
Here are a couple of articles I ran across that maybe explains how this works better than I do.
https://www.hotrod.com/articles/ctrp-0408-power-steering-systems/
https://auto.howstuffworks.com/steering4.htm
https://www.fourwheeler.com/how-to/power-steering-103/
But I'm not sure it was a Saginaw box.
It seems those use a torsion bar as a spring. The stronger the bar, the harder you have to turn the wheel before the boost kicks in and thus determines your road feel.
Since the weaker the bar, the less you feel, makes me think your torsion bar has come loose or broken inside the box.
Here are a couple of articles I ran across that maybe explains how this works better than I do.
https://www.hotrod.com/articles/ctrp-0408-power-steering-systems/
https://auto.howstuffworks.com/steering4.htm
https://www.fourwheeler.com/how-to/power-steering-103/
So I just picked up the truck. Feels a lot better but I have to bring it back on Monday so the can adjust the caster. It is off by 2.7 degrees. It’s kinda sketchy to drive at 50mph and up. I’ll keep u guys updated. Thanks for all of your help!!!
You can differentiate a bit between assist and alignment by how much more pronounced the problem is while driving vs. Sitting still. Another quick check is whether or not you feel the front of the vehicle raising up when you turn the wheels from center (parked). This is part of how the caster centers the steering- the weight of the vehicle is pushing the wheels back to center.
Just ran outside and moved the wheel while standing out side the door. Truck stays perfectly level. I don’t know why I didn’t think of any of this stuff.
I had the same problem with my truck where it the steering would not return to center. It turned out to be my dana-60 king pin springs pre-load was too tight.
Yes if the pivot does not turn smoothly it will hinder the return to center. So if the caster is good it may be ball joint or King pins
They could still be too tight.
I agree... everything is very tight right now. But I’ll see what happens after the caster gets fixed
How did you set the tension on the spring eliminators?
I didn’t and I’ll tel you why. When I put my knuckles together everything was going good till I got to the top. The Reid bushing did not sit flush with the top of the knuckle. Which is fine but the bushing also didn’t fit inside or the recess in the arm. I read a ton or forums on this same problem. So when you bolt the arm to the knuckle there is a ton of tension until everything jives together. So before I even installed the preload screw and jam nut the knuckle could barley be moved. I read some people chamfering the arm some chamfering the bushing but most just gave it a couple hundred mile and it worked it self together then you can start setting preload. The washer on top of the bushing would giggle around freely so it not a case where the washer was to thick.
That could be the lack of return. I would expect the steering to be stiff, with added friction in the king pins.
The truck is still all over the place at about 40mph... hard to tell the speed speedometer is really far off
To little positive caster will cause this symptom.
The caster is off... they told me that on Saturday. They told me to bring it back on Monday to have the older tech look at it and see what could be done. I’m kinda getting irritable with the alighnment shop cause I called on Friday and asked “if the caster is off can you A. Get the shims? B. Put the shins on?” Both answers were yes. So I dropped the truck off on the way to work and just gave him a call. They don’t seem to know what they are doing. I had asked them if they were able to work on older cars and they said yes.
I though my last post was unclear. The truck was there on Saturday and they fixed the tow then I dropped it of today(Monday morning) so the older tech can look at it. I called them today and they don’t seem to know what is going on.
Back when I had a '56 Chevy pickup,with a straight axle and leaf springs up front,I wanted to lift the truck up more in the front ,so I bought a set of those long shackles that were so popular on 60's muscle cars..truck rode hard ,had only 1" of clearance between the bump stops and the spring pads,and bottomed out often,so I figured longer shackles would gain me some more "space" there..
That truck had the shackles in the FRONT of the front springs !--just the opposite of the 4x4's we are familiar with..did not make sense to me,but GM must know what they were doing ?..
I managed to get the shackles installed ,but had to use the lowest set of holes (that lifted it the most) before I saw the truck go up much--the leafs looked like they were going to bend the wrong way when I hit bumps,but what the heck--I went for a ride,and it was much smoother!..all was well,until I got on the highway,and got it up to about 50 mph..
The truck was darting ALL over the road,switching lanes by itself,like I had a lot of slack in the steering linkage...didn't go 5 miles before I got back off,and took back roads home...tried "lowering" it by moving the bolts to the other holes in the shackles,but it didn't help much--even in the lowest setting the shackles were still about 1-1/2" longer that the originals..
I went to an alignment shop and showed one of the guys there the truck--after he stopped laughing,he said "well-your problem is not enough caster--maybe you could put wedges under the axle to tip it back and get more positive caster..he even gave me a couple wedges that were about 3/8" thick on the fat end and tapered down to nothing...it sucked getting the u-bolts loose,and there was barely enough threads left to tighten them with the wedges installed..
Truck still darted all over the road,maybe not quite as severe as my first ride,but when you hit any sealer or ridges in the pavement it wanted to pull you into the ditch,or the other lane..
I ended up putting the original shackles back on,then it was very stable,but steered like a semi with no P/S,too much caster now,it also had a death wobble after 40 mph under certain conditions,one bump in the road would set it off---so I took the wedges out from under the spring & axle too...back to normal again!..
A lot of effort wasted for no gain!..but I learned a lot about alignment..
That truck had the shackles in the FRONT of the front springs !--just the opposite of the 4x4's we are familiar with..did not make sense to me,but GM must know what they were doing ?..
I managed to get the shackles installed ,but had to use the lowest set of holes (that lifted it the most) before I saw the truck go up much--the leafs looked like they were going to bend the wrong way when I hit bumps,but what the heck--I went for a ride,and it was much smoother!..all was well,until I got on the highway,and got it up to about 50 mph..
The truck was darting ALL over the road,switching lanes by itself,like I had a lot of slack in the steering linkage...didn't go 5 miles before I got back off,and took back roads home...tried "lowering" it by moving the bolts to the other holes in the shackles,but it didn't help much--even in the lowest setting the shackles were still about 1-1/2" longer that the originals..
I went to an alignment shop and showed one of the guys there the truck--after he stopped laughing,he said "well-your problem is not enough caster--maybe you could put wedges under the axle to tip it back and get more positive caster..he even gave me a couple wedges that were about 3/8" thick on the fat end and tapered down to nothing...it sucked getting the u-bolts loose,and there was barely enough threads left to tighten them with the wedges installed..
Truck still darted all over the road,maybe not quite as severe as my first ride,but when you hit any sealer or ridges in the pavement it wanted to pull you into the ditch,or the other lane..
I ended up putting the original shackles back on,then it was very stable,but steered like a semi with no P/S,too much caster now,it also had a death wobble after 40 mph under certain conditions,one bump in the road would set it off---so I took the wedges out from under the spring & axle too...back to normal again!..
A lot of effort wasted for no gain!..but I learned a lot about alignment..
