I need some feel for the following issue I'm having...I'm leaning towards the hydroboost or the steering gear being bad, but read on. About two months ago, the steering started hanging up...mainly in the AM (cold fluid?).

I would turn out of my driveway and the steering would seem to "lock" partially turned. It turns out that it will still turn, just with much input and if you simply bump the steering wheel in the direction its lock (to the left if the wheels are locked left), it instantly frees up. By much input, I mean more than that required even if the power assist had just failed (almost like you're fighting the power assist itself). It will turn, but it is extremely difficult (I'm six foot, 250 pounds...just for reference). It happens unpredictably, and randomly (but NEVER at highway speeds)...always just after making a turn (typically left from what I can remember) from a stop.

One thing I noted was that you can hear the pressure from the PS pump diverting when it does it...so I think the assist it trying to assist, but something is preventing it. I have always heard the psss....psss....psss when the wheel is turned (from new), and that hasn't changed...and when it hangs up, you can hear it as you try to force the wheel (indicating the pump is working).

At first, I thought it might have been a piece of dirt in the system...hung a valve open, etc. But now that it is a routine thing, it can't be that. FWIW, the system has been evacuated and refilled multiple times throughout its lifespan...currently 225k.

I installed a RedHead steering box last fall (almost a year ago)...I hope that's not the culprit. Its not linkage binding...its definitely something hydraulic or steering gear related.

Anyone have a thought on what I might be looking at?

 

My guess would be a bad u-joint.

It really sucks when that happens going down the road at 60mph.

Intermittent steering - what a concept.

 

How would a u-joint affect steering??

I have the dynatrac hubs...sorta eliminates that as a possibility.

 

The steering shaft has u-joints on it. I'd look at it.

 

That was one of the first things I looked at...the steering shaft appears fine.

I've checked all the suspension parts for binding, basically I checked all the simple stuff...if it was something like that, I would expect it to happen every time, and not this infrequently (or at least be duplicated upon command)?

I've ran a wrench over everything I've had off from last year...

 

So your front axles don't have u-joints?

 

Not that "move" when the hubs are unlocked...they would not affect the steering. Besides, they are in good shape and greaseable. Now a balljoint I could see, but they have been replaced too.

This truck is well maintained, not like its been neglected. I know the condition of all the typical wear items...I use this truck to get me from one side of the country to the other, I probably spend more time under my truck than some people spend behind the wheel. Like I said, I have eliminated all the easy stuff...balljoints (replaced last year with greaseables) are good and smooth (no tight spots), wheel bearings are good, all the front suspension joints are good and smooth. I checked the support bearing on the steering brace, its good.

The only other thing I could imagine would be if the steering stabilizer (replacement Monroe) is hanging up? Maybe its valving has become faulty? But it doesn't occur when I have the truck on stands.

 

So then the variable is the wheels aren't turning.

Just curious, what was the outcome on this? Seems like a pretty important issue others might benefit from a better understanding of.

 

I recently installed a filter on the PS system, and the problem/issue has not returned. I can only assume that it was debris in the system that would hang up something from time to time.

 

I'm a big proponent of filters and coolers.