Sticky or stiff or sticking steering (solved)

Thanks for your post @Cowtc . I have the same issue on my 2008. Tires fine, alignment just done. The steering is fine and light but in a straight line it sticks so you have to make constant adjustments. On a very slight curve the car will continue the turn if you let go of the wheel. It doesn't want to re-centre. It is the same in both directions. I want to call it stiction, like a computer hard drive that won't start spinning unless you shake it.

I tried new Mevotech shock tower bearings, still stiff. I then regreased the old ones and went back to them. No change.
With the car raised I disconnected the tie rod ends and checked for stiffness of the shock tower by turning the steering knuckle by hand. It was smooth and easy to rotate. No stiction.

I disconnected the steering shaft and compared the turning effort of the steering column with a 2005 parts car. Overcoming the initial stiction was about the same for both.

I compared the turning torque on the rack with the rack of the parts car and it took 4 more inch pounds to overcome the stiction: 26 inch pounds for the parts car and 30 inch pounds for my 2008. (I controlled for friction of the tie rod ends dragging on the subframe by supporting them to make movement frictionless.)

Does anyone know the torque required to start the rack shaft turning? Has anyone ever regreased the rack? I doesn't look easy, especially with the large 12 point female plug. Torque values would be important or maybe you could do it by feel. What grease would be best?

I could simply go to a wrecker and get a new rack but the two torque measurements I took seem close and maybe the rack is not the problem.

Any suggestions would be welcome. Thanks everyone.

 

,are you aware there was a tsb offered about 10 years ago for a steering intermediate link that could fail or bind the steering? It was a big deal nationwide recall.

It was the same time they offered to chop the bottom of the gas pedal off to prevent runaway Prius from jammed floor mat.

There’s not much to grease steering rack wise unless the rubber boot failed failed there’s 2. Previous poster did a nice job checking the strut steer bearing they fail. But be aware you tested that bearing unloaded with no weight on them. There is tremendous weight on those bearings the entire front end.

I had my struts replaced at 100k miles and the steer bearing too and got 100% easier steering effort. Major improvement. If you have 150k miles or more I would buy new struts and steering bearing. They are a maintenance part. The factory struts only last like 80 to 100k.

 

Here is a follow up on my steering rack adjustment.

It worked! Steering is light now with little to no stiction. I loosened the large plug that holds the rack against the worm gear. I also had a bit of a dead spot at the gears. It might have been the rack but I decided to swap the worm (pinion?) gear because I didn't want to remove an inner tie rod to get at the rack. That seemed to solve it. I didn't regrease because the grease looked fresh. It had a jet-black grease that was probably lithium based and I didn't want to chance it with what might be a lesser quality grease.

I didn't have a 12 point torx that big so I used a 15/16" nut and a 15/16" socket. That worked. It was not too tight and came off fairly easily with the rack in a vice to hold it. It looked like they used a grey coloured gasket goo so I reassembled it using Hondabond (same colour and texture when cured).

 

Another follow up.

Working great. I was on the highway and the car had fingertip steering. It was a night and day difference. I caught myself going 125kph which I would never have done before when it was sticky.

For anyone who has the rack out or had dropped the cradle I highly recommend that you at least check the stiffness. Grab one of the tie rods then push and pull it. If it is sticky or notchy just loosen off that adjuster. You will probably have to completely remove the plug to clean up the threads so you can make fine adjustments. Use gasket goo on the locking nut to seal it.

There is a spring behind the adjuster plug which you shouldn't allow to drop, roll and hide in the corner of your garage under a heap of fossilized valuables but nothing about the job is really hard once the rack is out. I tried measuring the torque needed to overcome the stiction but you don't have to go that far. Besides, my torque wrench was at the bottom of its range and probably wasn't accurate at all. Just adjust it until the rack slides smoothly in the housing. Think like Goldilocks.

 

My 2012 Prius Plugin had the "sticktion" problem also. It wasn't too bad but was extremely annoying on road trips. It took a little tug to move the wheel just to make a small correction.
I started going to a car wash that spray waxed the car. I noticed the sticktion problem went away but came back within a week. Same thing after another car wash.
Checking into it further, after I removed the front tires and tie rod ends, the right wheel hub moved a lot easier by hand than the left wheel. So I put in new KYB struts from Rock Auto and after an alignment the sicktion problem is gone. It's been two months.
I assume that the car wash lubricated the struts???
I suspect the steering rack is still the real culprit and the stiff turning strut just brought out the problem to where I could notice it. So not a real fix- just kicking the can down the road.

BTW, now I have a slight clunk when I back out and turn the wheel. Not related to the sticktion problem, it might be a bad ball joint. I tried to replace it but stripped the nut flanges doing so. Thinking of welding a socket to it. (Disconnect the battery and put the welder ground on the socket. What do you think?)

 

Athos I need more information. Is the big torx an adjustment for pressure on the rack? So just back it off a bit and lock down? Can I do it with the rack in the car?
I have been trying to fix this, my car failed state inspection because of this problem. Thought it was a lubrication issue and filled the boots with oil which helped but didn't completely fix. Seems you found the problem, most of the time steering gets loose with age and more tension is required but not the case here I guess.
TIA