Intermittent, random, stiff steering

Hello all,
My 05’ Tacoma has began a weird symptom of the steering becoming stiff at random intervals, not speed dependent nor wheel position dependent. Suspension is stock, tires are 265’s instead of 245’s, everything else is stock. Power steering pump makes no noise and nothing is leaking. The only pattern I’ve noticed is the truck doesn’t do it when “cold” (NC in the summer so that’s relative) but it does it 2-4 times a minute when warm. Then it’ll go 5 minutes without doing it and begin again.

So far I have,
Replaced the lower intermediate shaft u joint with a quality greasable unit (Tuesday). That went well, no issues. Upper universal and rubber coupler disc are in good shape.

Today I flushed a full qt of DEXRON 3 through the power steering system. The symptom didn’t begin as quickly this time relative to drive time and under hood temps but it did begin acting up after 15 minutes of driving. (FYI don’t trust the sight marks on your reservoir if your truck has some mileage on it, my 240,000 mile truck has a stained reservoir that doesn’t reflect the actual level until it’s above the hot low mark!)

The best way I can describe it is driving the truck with my arm perched on the door and my hand at 12’ o clock on the steering wheel it takes double to triple the regular effort to initialize any turn, then once through 5-10 degrees of motion the full power steering assist comes right back just like normal. Like something in the PS hydraulic system is resisting flow and once that resistance is gone the system functions perfectly normal till the obstruction/resistance returns.

Sound familiar? Please chime in and share in the fun!

 

Did you cycle the wheels completely from side to side multiple times to purge air for the PS pump?

 

Correct, with the wheels off the ground and on the ground. Engine off and engine running. Plus 20ish miles of road driving.

The pump makes no noises whatsoever like most PS pumps do when air is in the system. (In my experience)

 

Another interesting thing is the steering wheel will remain in the “stiff” position until I actively move it away. So if it gets stiff in a sharp turn, the truck will hold the turn and the wheel won’t revenged itself like it does when the steering issue isn’t manifesting itself.

I don’t usually notice the stiffness through the turn, it’s only the initial movement required to get the wheel to turn. There’s no binding once the wheel is rotating which suggests to me that it may be hydraulic and not a mechanical issue. I’m thinking PS pump, rack or lines. No fluid loss after 30 miles of driving today.

 

it could be your steering rack but your ball joints could be binding up. my steering was pretty stiff for a week or so after had a new ball joint installed. I could see how an old one could bind up and cause stiff steering.

 

Interesting thought, I have a 3rd Gen set of struts to put on my truck, this may be a great time to take the tie rod ends off the knuckles and pivot the knuckles by hand. I can go ahead and install the TRD/Bilstien struts while I’m in there.

Are there any other ways to check for a binding ball joint? The drivers side all looked good with the boots and seals intact on Tuesday when I fixed the steering shaft.

Not disputing you, but I’d expect a straight mechanical issue like that to be more consistent and easier to duplicate. The ball joints may be dry and seizing but shouldn’t be temperature dependent I’d think.

 

have you done anything that could have bent the rack? If not, i would think the pump the most likely culprit.

 

Nope, I don’t wheel the truck at all. It just started this about a month ago. I don’t use it as my daily driver anymore so I’ve only put about 150 miles on it since this began. The used car dealer I bought it from told me the prior owner had replaced the rack and the clock-spring, I saw “alignment” tape on the steering column so I wonder if the prior owner wasn’t chasing this 40,000 miles ago before I bought the truck. If the rack is new I’d be surprised as the rack bushings allow a lot of flex. My goal is to get a full poly bushing kit and go over the truck this fall.

I’ll add the TRD goodies then, including some TRD bronze beadlock wheels!!

 

i'd get under the truck and check all the steering/suspension components. make sure nothing is bent.

 

Will do, thanks for the suggestion!

 

Similar problem.

https://www.tacomaworld.com/threads...hile-pressing-the-brake.716971/#post-25523200

 

This would not be my first guess, but easy to test. Lift the front up and with engine off, take the wheels lock to lock and feel for binding. Furthe BJ's tend to get sloppy, not bind. Your steering rack has a torsion bar that senses turning forces and transfers that to spool valves that open to send pressurized fluid to the pistons for assist. Sounds like problems in that unit. the initial light force is not opening the valves, but once they finally do open with more force, all works fine. Possible it is an oring in there (probably 20+ in the assy) and thy sell kits. Lot of work and possible it is also a worn steel part that you cannot get. Probably best to go with a new or reman rack. Carefull of the cheaper remans, as several are sloppy and don't bring it back to OEM specs.

 

I agree 100%, I’m not a steering system expert but this makes really good sense to me. I’ll dig further into this angle and see what I come up with. Thanks!

 

I’m still digging into this one, I’m known for overlooking the basic issues while trying to reinvent the wheel to find an obscure issue so I started with the basics.

The lower steering shaft U-joint has been replaced, I also replaced the (unknown origin or age) serpentine belt. When I changed the belt I noted that the tensioner felt strong and the belt doesn’t hop when the engine is idling.

In driving the truck about 6 hours yesterday I noted a few peculiar things. The issue seems to be most likely to occur while accelerating or at cruising speed. I have yet to see the issue occur at idle regardless of the surface I’m parked on.

When accelerating through a turn the steering wheel may stiffen up in what ever position it was left in. I can override it by pushing either way to turn as needed.

The last really interesting thing that points more towards the PS control valve and it’s torsion bar/valve assembly is, if I’m driving straight down the road and I feel the resistance when turning one way or the other I can turn the wheel 5-10 degrees in the opposite direction on the stiffness and it immediately unlocks and full power steering is restored. Almost like the torsion bar is loose in its housing or something and not diverting PS fluid into the proper side of the rack until the wheel is turned 30+ degrees.

I wish the issue was more repeatable and less random. When cold the truck performs flawlessly everytime, when warm it can happen as often as 5-6 times per minute or it can go 10-15 minutes operating perfectly before malfunctioning again.

It’s puzzling to see something mechanical like this be so random. Perhaps an oring has failed internally as noted before. I’ll keep this thread updated.

Parting thought, my rack bushings are worn to the point that the bump steer was immediately noticeable when I test drive this truck before buying it. That was at 200,000 miles, it’s just over 240,000 now. Could excessively worn rack bushings be taking the steering input force I apply to the wheel and not transferring it to the rack control valve which are supposed to be hard mounted to the rack in the chassis? The rubber bushings would likely get softer as I drive, from flexing as I steer and from ambient engine bay heat softening them? Thoughts?

 

The more I think about the bushings the more sense it makes, my last set of tires had even showed some uneven edge wear at the outer edges of the tires that would be consistent with loose and shaky toe settings. When I was diagnosing the truck a couple weeks ago my Dad moved the wheel lock to lock with the wheels on the ground and the rack appeared to be moving 1/4”-3/8” independently of the chassis.

 

That sounds like rack bushings or bolts to me. Have you checked the torque in the rack bolts? Very possible PO or their mechanic didn't torque them correctly on reinstall.

 

Double check torque specs, too.
Even when I thought I was right, I've been wrong.
Lots of incorrect numbers floating around this site.

 

I’ll do that, I have no idea about the age, or mileage of the rack on my truck. I don’t think it has ever been wheeled or lifted but I’m not 100% sure what it saw before I owned it.

I ordered the Energy Suspension master bushing kit last night. Found it for $283 with two day shipping! Seemed like a steal to me.

I’ll check the bolt torque but more than likely I’ll go ahead and install the poly bushings and be done with it.

 

@OP - Were you able to find the cause? I have an 05' doublecab pre-runner with 225K miles and I had very similar symptoms. I replaced the PS pump almost exactly a year ago and that resolved the issue. As of this week, the issue is back. Stiffness at random points of turning, not wanting to return to center on its own, and all at random times. I drove home from work last night and it was fine ( 20 miles on Frwy/7 miles in town). This morning was stiff at random points again.

 

Good morning,
Sadly no, I got the master bushing kit and never moved any further. My issue seems to be temperature related though.

In addition to getting another car that I drive more frequently than the Tacoma, I also found that the cooler weather seemed to have resolved my issue.

I do feel more free play in my steering wheel now that I did before, that really makes me think it’s a rack issue and no a pump issue.

If/when I address it, if I get a resolute answer, I’ll absolutely let you know.