Too much power steering?

[Old_rusty]

Hi, first time caller, long time listener.. And quite a amateur when it comes to cars so bear with me..

Been a happy Blazer-owner (K5 -87) for a year or so, and when I changed to summer tires (35") I noticed some play in the steering. Located it to the steering box. Changed it to a new. And wtf. First bump I hit I was all over the road thinking "Holy mother of **** what have I done?" Wasn't even bump-steering that bad with my old steering box on its worst day..

Then I tried the same bump without any hands on the wheel. Straight as an arrow. So Im the bump steer. When my rock-hard-pulverize-youre-spine-suspension makes me jump, the movement goes straight to the tires with a full servo-assist which makes it swirl on the road. Lane changing is done pretty fast with parts of an inch movement of the wheel.. And the wheel has more or less no resistance at all..

Now:
Is this normal? Did I get the wrong gear ratio? Faulty steering box? ****ty driver? Is it possible to increase the resistance somehow (steering damper was changed a few month ago)? Or decrease servo assist?

Have driven it for two days now and starting to get used to steering with one finger, but I would never, ever let anybody else drive it. So it would be nice to have a bit less power steering..

Grateful for any input.

 

[Amtek]

Definitely sounds like the wrong ratio and it sounds dangerous, what if you sneeze? Did you measure how many turns from lock to lock? Is the pitman arm and steering arm all stock? I gotta move my steering wheel about 20 degrees (about 3-4 inches) when changing lanes at highway speed. Chevy's seem a little over-boosted compared to fords but you should still get some feedback through the steering wheel.

 

[Hogback Fabrication]

Sounds like bump steer and a sloppy box that was hiding it before.

Is there a lift on the truck, and if so, how much?

If there is a lift what do you have for steering correction?

 

[Fordum]

First of all, I hope you checked for frame cracks when you had the box off, and have the brace and strengthener.

Now, as to your problem. You definitely have one problem, but not sure about the other.
When power steering is working, the load you feel when you try to turn th wheel is not the effort necessary to move the tires.
What you feel is the effort needed to twist a torsion bar spring in the steering box.
If the box were not connected to anything, when you turned the input shaft, the output shaft would turn and you would only feel the gears and bearing friction.
But, since its hooked up, when you turn the input shaft, the output shaft does not move. Instead the input shaft twists the spring which is hooked to the gears.
When you twist the spring, that causes a spool valve to move which allows fluid to apply assist.
As it moves the wheels, the spring straightens and the spool valve re-centers and turns off the fluid flow.
Of course, if you keep turning the input shaft, the spool valve opens or closes depending on how hard you twist the spring.

So, for whatever reason, the torsion bar spring in your new box is very weak.

As for the ratio, it may be wrong also. That is easy to check, just count the number of turns from lock to lock and ask what others have.

As for changing the steering load, there used to be companies that would rebuild your box and give you whatever load spring you wanted.
But, since you have a new box, I would take it back. But I would check the number of turns first.
The spring tension is probably just a mistake, but there is no way they could have accidentally have made the ratio wrong. So if its wrong, you must have the wrong model box.

 

[Old_rusty]

I think its stock pitman arm and steering arm (many owners before me, I didnt lift it), lift is about 3". Regarding steering correction you have to explain to me what you mean..

Since my steering wheel is off centre as well I will fix that this weekend and come back to you with how many turns it has and with a more through description of lane changing angels of the steering wheel. My experience is that without proper measurement one might exaggerate things.

I really appreciate you taking time to answer my questions.

 

[496truck]

From the steering box you have a pitman arm
The pitman arm connects to a drag link assembly which is made up of 2 tie rod ends (drag link ends) and an adjuster sleeve.
The drag link connects to a steering arm which is bolted to the top of the steering knuckle.

Pitman arm - Drag link - Steering arm

What you want in this style of steering system (known as push/pull steering) is a drag link that is as close to level as possible. What happens when this truck is lifted is now the drag link will be higher at the pitman arm and lower at the steering arm. This drag link angle will cause many problems like bump steer and wear on the drag link ends.

You can correct this in 3 ways:
1st a dropped drag link. DON'T DO THIS!!! They are not a good fix for this.
2nd a dropped pitman arm. Usually only able to be found for 2" lifts.
3rd a raised steering arm. This will work on 4" lift.

You need to find out what lift you have and if one or none of these have been changed before going any further. Of course, if your truck is sitting level and you look at the drag link and it is level than it should be all set.

And the ultimate steering correction is to change the truck over to cross over steering. But I'm not addressing that right now cause you are working with the stock set up.

 

[Old_rusty]

Checked the span of my steering today, 1.75 turns in each direction. Will have to google a bit I guess to check if thats normal.

Regarding the drag link it has a drop of about an inch. I have another steering arm in a scrap heap and will check if that can compensate to get it levelled.

Regarding my power steering I beginning to wonder if it wasn't just the shock of going from a bad steering box to a fully operational. Starting to get used to it, still a bit to much for my taste but a few more miles and Ill probably be fine with it.
Will go to a friend of mine with two Blazers though next week and see hos his rides, both stock and with 38".

Again, thanks for the help.

 

[Amtek]

Is it 1.75 turns from full lock to lock? Cranking the wheel all the way to the left until it stops then from there counting how many turns it takes to go all the way to the right until it stops?

Or is it 1.75 from center to left/center to right?

It should be a little more than 3 turns from lock to lock (havent driven my truck in a good while so I cant verify right now) If its only 1.75 turns from lock to lock then that will make your steering extremely sensitive.

How about taking a photo of your steering linkages and box so we can see?

 

[imiceman44]

Is it 1.75 turns from full lock to lock? Cranking the wheel all the way to the left until it stops then from there counting how many turns it takes to go all the way to the right until it stops?

Or is it 1.75 from center to left/center to right?

It should be a little more than 3 turns from lock to lock (havent driven my truck in a good while so I cant verify right now) If its only 1.75 turns from lock to lock then that will make your steering extremely sensitive.

How about taking a photo of your steering linkages and box so we can see?

He said:
1.75 turns in each direction
Which means it's 3.5 turns lock to lock which means he has the right ratio, but probably a defective box, I say return it and get another one.