From what I am aware of my car has a power steering rattle, where the driven (plastic) gear has been worn excessively and a rattle (gear backlash) becomes apparent. Instead of replacing the whole column to "fix" the issue, has anybody tried to rotate / reclock the driven gear 180°? If anybody with this problem has tried driving on a gravel road at low speed (where EPS is most active) you will readily notice this rattle, but if you take the wheel, left arm at 12, and move it to 10 or 9, you will notice that the rattle goes away. This suggests that most of the gear lash issues are around the normal (straight forward position) which would make sense since the amount of time spent at the normal condition is much more than any other position, making the normal position on the driven gear a high wear zone. Basically I am wondering if anybody has attempted to reclock the driven gear 180ish° to suppress this gear lash issue.

TLDR; powersteering geartrain rattles, has anybody played with it to supress the noise?

Any input is appreciated.

 

Sure its not just your intermediate shaft? Those are way more prone to rattle than anything else in the column.

 

Yup, as I increase speed to 20+ mph the rattle dampens out since the powersteering controller's gain reduces (sensitivity). Furthermore, the issue isn't there if I unplug the EPS unit.

 

Just spent the afternoon working on my car addressing the same problem among other things. I thought it was the intermediate shaft and was going to replace it but its tight and operates smoothly and is definitely not the problem. I also changed the lower control arm rear bushings which will take care of some of the front end rattling, but I can definitely feel the play in the steering mechanism when I rotate the wheel back and forth with the car not running. I'm also having problems with the wheels not returning to the straight ahead position when coming out of a turn. I am thinking its time to replace the rack, but I also understand there are some electronics at work here. Do I have a combination of problems?

 

The intermediate shaft is a common problem in GM vehicles. You won't really be able to feel play in the shaft. The original tsb required a certain grease or lubricant to fix the issue but the rattle would usually start again after a few months. Eventually they just started replacing the shaft.
Your wheels not returning back to a straight position after turning could be a bad alignment or tire wear. I would get that checked first.

 

He just said it's not the I-shaft. This is a different clunk.

My car does this too, you can feel the backlash in the motor. I wonder if replacing the power steering motor will eliminate it?

 

He said he checked the shaft for play. It will still rattle even if it doesn't feel loose or have play. I worked for Saturn dealers for 4 years, and we never replaced an eps motor because of a rattle.

 

Your thinking of 2 different clunks. When its the intermediate shaft or rack, its a very loud clunk thats audible over the smallest bump. The backlash in the gear is alot more subtle that you can hear by turning the steering wheel from 11-1 quickly with the car off.

 

No, I know exactly what Im talking about. The shaft will make noise whether your on a rough road or sitting in your driveway wiggling the steering wheel a few inches. I'm not going to argue about one of the most common issues to plague GMs for over a decade. It's your car and your money to waste, but I can pretty much guarantee that if you take your car to a dealer the SA or tech is going to get in, wiggle your steering wheel, and tell you the intermediate shaft needs to be replaced or greased. It's that simple.
If you guys find it needs to be replaced you can find the shaft for pretty cheap on Amazon sometimes. I got mine for around $70 a few years ago. It's pretty easy to install as long as you don't mind cramped spaces.

 

Relax. My post wasnt even in response to yours. Ive chased this problem multiple times. Yes the shaft is a common problem. Find a spot in my post where i said it wasnt and ill shut my mouth. The gear backlash is also a common problem that can be heard after you replace the shaft

 

Yes, but you test the two in different ways. The shaft you can tell simply by wiggling the steering wheel. I'm not %100 sure how you do it but to see if it's the motor you have to drive the car on a rough surface and turn the wheel, then release it to see if you can hear the noise when it spins back, or something like that. I had a tech drive my car when we checked for it and it was like 5 years ago so im not sure if that's exactly how you do it.

 

You can hear both just by moving the wheel in my experience. The shaft is a very loud clunk and the wheel will have more play in it. I replaced both the shaft and rack at the same time and all i was left with was a much quieter clunk/click with a tight wheel.

 

When I had my rattle.... I ended up replacing control arm bushings.... sway bar endlinks... sway bar frame bushings.... and lastly the intermediate steering shaft. BOOM. No more rattles.

 

So, ended up getting an amazon card from work, thought "screw it" i'll through an I-shaft at it. No difference. Semi annoyed, went to the local scrap yard, bought a EPS unit and slapped it on in. Bam! Not the slightest rattle, well minus the sunroof but that is a whole other issue.

 

Glad to hear you figured it out, sorry it wasn't the shaft. My motor is on its last leg and it still doesn't make noise. I guess you just never know.

 

Wasn't really the motor that was the issue, its the gear-train that it connects to that has excessive backlash. Less noticeable at speed since the EPS unit becomes less sensitive as speed increases.

 

So I guess I was right.....

 

Yes, you were right.