Steering clunk over rough roads

[FRSBRZGT86FAN]

Originally Posted by 73TORANA!

Nah sent it via emails and on the Toyota face book page and I have now been blocked from there page, mind you i was polite and non abusive, they did reply but did not want to enter into any further discussion saying my case is closed as its a characteristic. Toyota request you use electronic media to contact them, easy to delete i guess. I have also lodge a case with the ACCC, waiting on response. I have written to Wheels magazine, Toyota Japan and there general manager, Tetsyuya Tada, Toyota global, to JTEKT, the power steer manufactures and to Paul Gover a motor journalist. No reply from anyone as yet. I have a few more to try but its a really disappointing but I'm not surprised and im not gunna give up. Might have to try paper mail.

How do you contact Tetsuya!?

[73TORANA!]

He has a face book page. Not much activity on it but I sent him a message pleading for help. Ha Ha I only joined F.book to contact Toyota and got blocked with in 3 days.... Beat that !!

[ZZT86]

Send via snail mail to Akio Toyoda !

[Gords_zenith]

Originally Posted by 73TORANA!

Hi all, Ive done a lot of research over the weekend and today and come up with some interesting results. I was able to simulate the exact same noise that we have grown to hate in both cars sitting in the drive way but not to the same extent as driving over rough roads so i am 90% convinced its not in the suspension, rack or intermediate shaft but in the power steer unit.
The Electronic power steer unit or EPS is made by JTEKT a sub company of Toyota I believe. JTEK make all sorts of automotive stuff including the Torsen LSD in the 86/BRZ. The column P.Steer or C-EPS has / is used by countless brands and models including Toyota Corolla so i had a look at the 86 and my 2009 Corolla and they are 99 % identical, DAM. On the JTEKT web site i stumbled across some engineering publications and in these I found that they have been chasing an issue that they call rattle and back lash of the worm drive gear in the C-EPS, one artical also mentions inverse input, I.E input forces from the wheels over rough roads ( bumps)to the C-EPS and how the C-EPS dampened's these inputs via electronic inputs so the driver does not feel these input forces from the road at the steer wheel and that this dampening may increase rattle backlash over rough roads. They also mention in depth how they have tried to reduce this "rattle" and development is on going. So it seems that any car that uses this type of C-EPS has the potential to make this noise over rough roads. I have added a link if anyone would like some light reading, I will be seeing Toyota tomorrow armed with this info.
Click on the link http://eb-cat.ds-navi.co.jp/enu/jtekt/tech/ej/index.htm scroll down to the blue journal, No.1009E 2012 Automotive Technology Special Edition, click the drop down list and scroll to TECHNICAL REPORTS then the 4th line down click on Development of rattle noise analysis...... there's also and artical the 2006 journal.

So it seems if we want this fixed we will all have to make a noise !!

Thank you. I knew I wasn't crazy! Maybe they can tighten up the slack within the worm drive unit with tighter tolerances or use some Bellevelle washers to absorb shock and take up the slack.

[FRSBRZGT86FAN]

Wonderful job this research deserves a bump and sticky....

[troek]

ive gotten this issue since day one. theres no play in the steering, and the car drives great so ive always just attributed it to some flaw in the steering rack design or something. its good to know i may have not been too far off.

[73TORANA!]

Just in case you have missed the link on the previous post this JTEKT 2012 rattle update is a good read, its a bit tech "o" but its interesting.
Yeh troek my steering is great as well and I have had it independently checked twice by different companies. I think its just a poor design. The computer is supposed to eliminate the shock vibration from bumps on the road getting to the steer wheel and in this process the power steer unit counteracts these vibrations so you feel very little or no shock from the road. It works well but the down side is the clunk. I am asking can the computer be reprogrammed to not be so sensitive in this area, still waiting... I managed to get a hold of the Aus marketing manager and he has agreed to look further into my case. Hoping to get answers soon. The steering i feel they will not do anything unless they get multiple complaints world wide, so get on to your dealers to lodge a complaint but im hoping they will sort out my noisy / sticky brake booster.

[gravitylover]

Since 2008 I've had a C30, Challenger, XV Crosstrek and now this BRZ and each of these cars have the same rattle/clunk through the steering wheel and it is terribly frustrating. Thankfully it hasn't been a problem but it feels terrible, like bad bushings in the steering rack or sometimes depending on the pavement it can feel like loose struts or strut bearings going bad. It's nice to know that it hasn't been a wear problem caused by too many miles or abuse I've dished out to all of my cars but it's annoying to think that it could be solved but hasn't been.

edit: Somewhat dry reading but now that I understand the problem I probably won't be as frustrated by it. Hopefully someday some smart dude will actually solve the issue and tighten up my front end for me.

[FRSBRZGT86FAN]

Originally Posted by gravitylover

Since 2008 I've had a C30, Challenger, XV Crosstrek and now this BRZ and each of these cars have the same rattle/clunk through the steering wheel and it is terribly frustrating. Thankfully it hasn't been a problem but it feels terrible, like bad bushings in the steering rack or sometimes depending on the pavement it can feel like loose struts or strut bearings going bad. It's nice to know that it hasn't been a wear problem caused by too many miles or abuse I've dished out to all of my cars but it's annoying to think that it could be solved but hasn't been.

I guess the manufacturers would rather not waste the time sort of like the fuel pump crickets if it's not a total detriment to the car and not everyone complains why fix it?

[Wilcats]

Its just weird how other 86/BRZ owners don't complain much about this. Are they that numb or are we just that sensitive?

[FRSBRZGT86FAN]

Originally Posted by Wilcats

Its just weird how other 86/BRZ owners don't complain much about this. Are they that numb or are we just that sensitive?

Probably inadvertently ignored because a clunk over a bump in this car is just deemed normal along with all the other ticks and restless

[73TORANA!]

Originally Posted by Wilcats

Its just weird how other 86/BRZ owners don't complain much about this. Are they that numb or are we just that sensitive?

Yeh I don't know, Im not used to plastic cars im a bit old fashion in the fact that if there's a knock or clunk it used to mean something was worn I guess im a bit pedantic in this area but still its annoying, ha there i go again. I have just fixed another rattle this time in the console that makes a total +10 fixed.
I love, hate, love, hate, love this car.

If Toyota don't come up with a fix I guess we will have to live with it or live without it ?