Bizarre Binding Power Steering Issue (1 Viewer)

[atomicshawn]

A couple of years ago I noticed my power steering would fade and not work sometimes when stopped to negotiate obstacles on the trail. The ps pump would get super noisy too so I figured I needed to flush the system at least if not install a new pump. Over the years I would also notice the steering would intermittently get heavy sometimes just maneuvering in a parking lot without rhyme or reason but never paid much attention, just figured i needed to get around to that flush... but never did.

A few weeks ago the pump started making noise sometimes just cruising around town, under a load. I also noticed the pump was starting to leak so I ordered a new OEM. The day I picked up the new pump the old pump totally failed. (Note: A loaded 80 series on 315s is not fun to drive without power steering.) After the new pump install and flush (the fluid was a little dark but not terrible and no metal) the ps seemed to work fine. I thought for sure the pump would take care of that intermittent binding issue but much to my dismay I have found it has not.

So I have spent some time trying to figure out exactly when the problem occurs, and here is the weird part; It only happens after the system is warm, when the truck is or is almost completely stationary, and when the truck is facing downhill. I turn it around uphill, maybe a 6% or so grade, and the steering is smooth as butter in a full sweep from left to right. I immediately turn it around and stop and it starts to get heavier and heavier the closer it gets to the stops, to the point that it feels like there is no ps. I think it has had this problem the whole time. Weird.

The gear is all I can guess. Any other ideas?

 

[T rex80]

If you have a decent lift and caster correction brackets, the tie rod can sometimes bind on the radius arms, easy to check just look on the top of the tie rod near each end for any rubbing marks

 

[T rex80]

Make that the underside of the tie rod

 

[rove_mcanus]

The steering box sounds like the culprit. Oil thins out when it gets warm, and thus gets past the seals easier. I've noticed alot of toyota steering boxes tend to leak internally causing hard steering.

The fact it doesn't do it facing up hill could just be the weight shift unloading the front end. Also being stationary is when the power steering works the hardest. Most fail because people spend so much time turning the wheels when not moving such as when attempting to park.

 

[djoneab]

The steering box sounds like the culprit. Oil thins out when it gets warm, and thus gets past the seals easier. I've noticed alot of toyota steering boxes tend to leak internally causing hard steering.

The fact it doesn't do it facing up hill could just be the weight shift unloading the front end. Also being stationary is when the power steering works the hardest. Most fail because people spend so much time turning the wheels when not moving such as when attempting to park.

So what is a fix for this? I think I might have the same problem with it getting hot also.

 

[atomicshawn]

So what is a fix for this? I think I might have the same problem with it getting hot also.

So are the problems you're having only related to temperature, or does it change if you're on a hill? (are there even any hills in Texas? )

I've gone over everything on mine again looking for obvious problems with the fluid lines and steering components as suggested (thanks T rex). Everything appears to be in order. So I'm afraid mcanus is right and this is where I'm headed next: https://forum.ih8mud.com/80-series-tech/443494-steering-gear-box-rebuild.html

Mine had pretty low miles when I picked it up and I'm thinking maybe the gear failure (if it is indeed the culprit) is due to lot rot.

I'm not looking forward to rebuilding the box, but I am at a loss at this point. I think I might try to check line pressure before I yank the gear just to see.

Based on my experience and what I have read here, 90+% of the time issues like this are related to the pump. If I were you djon I would look there first if you haven't already. Fluid flush first and if that doesn't help pump rebuild or replacement. Checking line pressure can shed some light and is probably a good place to start. Its what I would have done if my pump didnt already have obvious problems.

 

[Bishop97LC]

Similar problem but -

New power steering pump and steering gear box. Binds when warm only, steering at very slow speeds, like parallel parking. I believe the last owner disengaged the power steering paperclip cooler. Could this related? Is the atf power steering fluid to hot? Why would it be smooth at speed? Any help appreciated.

 

[leonard_nemoy]

Why would it be smooth at speed?

I know nothing but maybe it's just the same principle as driving an old truck with no power steering.

When your stopped it is super hard to turn and than the faster you go the easier it gets. It just the physics of turning a tire, the faster it's moving the easier it is to turn.

 

[baldilocks]

Similar problem but -

New power steering pump and steering gear box. Binds when warm only, steering at very slow speeds, like parallel parking. I believe the last owner disengaged the power steering paperclip cooler. Could this related? Is the atf power steering fluid to hot? Why would it be smooth at speed? Any help appreciated.

Is it binding as in sticking at a certain point then finally past that or does it simply lose power assist until the rpm’s are increased?

 

[mudgudgeon]

Jack the front end up and check that knuckles are rotating freely through full rotation without binding.
Trunion bearings could be toast.

You may need to pop tierods loose to check this

 

[harrydunn]

I'm going through something similar on my '97 LX. My '93 did not steer nearly this heavy. Power steering pump makes no noise, I have no PS pump bubbles, popped off my drag link and tie rod ends and the trunnion bearings are very smooth, although they do "snag" a bit in the straight ahead position since that is where they live the majority of their lives. Once you move out of that centered position "bump" they are butter smooth. Following along here...curious if a gearbox rebuild is in my future. Video below....

1997 FZJ80 Knuckles

 

[Bishop97LC]

Is it binding as in sticking at a certain point then finally past that or does it simply lose power assist until the rpm’s are increased?

Increased rpm's don't help. It's basically without power assist when fully warmed up and not moving much like when parallel parking.

 

[IdahoDoug]

I offer this only as a hail mary input. We recently sold our 92 LS400. A year before we sold it, the power steering began exhibiting an odd binding, though I never drove it enough to establish a pattern like you folks did. And I told the buyer what I learned. Apparently, there is a filter in the LS pump that can get clogged over time and fresh fluid won't clean it - some deposit. I learned out to clean mine by getting on LS forums and learning about this known issue, but never did - the car sat and was a loaner to people who came to town, etc.

Since some have replaced the pump with new and still had the issue, I wonder if there is a device in the lines (which presumably were not replaced?) that is quite common in power steering lines that is similar to a filter and may get clogged. It's a noise suppression device to prevent hydraulic whine. So perhaps that device is causing a restriction under certain flow and temp conditions, since it can happen with a mere filter clog. Best.

 

[harrydunn]

That’s good info Doug. I’ve been kicking around getting a pressure test performed. That could possibly uncover a blockage or weak pump scenario. I’m not sure if most shops have the equipment for that.

 

[Bishop97LC]

Increased rpm's don't help. It's basically without power assist when fully warmed up and not moving much like when parallel parking.

Correction, increased RPM is do help actually.

 

[Bishop97LC]

Correction, increased RPM is do help actually.

Actually, they don't.