Hi Evo community,

It's been a while since I've been here, but I've got a really long-standing issue I'd like to get your opinion on (so far I've read just about everything on the forums about this problem, including all of smike's excellent advice, so I know I'm not the only one!). Bear with me; this is gonna be long.

The car is: '06 Evo IX GSR, 133k miles

Problem summary: at freeway speeds, 60mph - 90mph, the steering wheel shakes. The shake may be minor (a few millimeters) or major (a good inch back and forth left to right). The shake comes and goes, sometimes the car rides smooth as new for a short while, sometimes it feels like I have a severely bent wheel. My hands and wrists are tired of this. When the steering wheel shakes, so does the whole car (of course) and I'm sure it's part of the cause for all my interior rattles.

How it happens: the shake occurs most often after accelerating onto the freeway (straight line), and will invariably occur after driving (at freeway speed) through a long sweeper. It may fade off for a bit (where the wheel sits perfectly quiet and still at 70mph) then come back on strong (both after a long sweeper or just changing lanes even). Clenching the steering wheel with my hands seems to help get things back in balance. I have not yet found a piece of road long and straight enough to see if the problem will recur if I only drive in a straight line.

What I've done so far to diagnose this:

• new tires all around Dec 2013 (Direzza ZII, oem wheels, 245/40/17)
• road force balanced all four wheels 2 weeks ago (they were out of balance for sure even after having them double-balanced at my standard shop) -- this made a noticeable difference but it's slowly getting bad again
• full front suspension inspection this morning (see odd notes below)
• replaced steering rack (oem unit cost me insane $, but it was leaking so... yeah) last year
• replaced various suspension components last year:
  • ohlins dfv c/o's, lowered from stock height ~1" (stock shocks were leaking)
  • whiteline front sway/poly bushings/links/rca kit
  • whiteline TREs
  • recently aligned perfectly at: -2.0/-2.0 camber front, -1.0/-1.0 rear; 0 toe
• replaced front-half of main driveshaft this morning (shop indicated it could get out of balance)
• replaced front driver side CA (oem) and axle a couple years ago (@80k miles)
• replaced all wheel bearings Jan 2014 (oem units including the hub)
• replaced all corners' rotors/pads countless times
• currently (Jan 2014): Baer slotted two-piece up front (Eradispeed) + Perf Friction pf01 pads
• new Exedy sport single-disc, PP, flywheel
• I think that's about it?

I'd say the thing that made the most difference was definitely road-force balancing.

Some odd notes:

• there is a tiny bit of play in every outer axle on the car (shop says that's normal)
• main driveshaft bushings are pretty soft rubber (also said that was normal)
• I've had plenty of issues with warping rotors and bad pad transfer, hence the many brake replacements (could be related?)
• on the lift, no wheel play in/out/up/down (solid)
• no free play in steering wheel
• the ball joints' boots (RCA kit) are torn on the inside facing the rotor heat shield, but there's no play and they're practically new (last year) and no grease is leaking (maybe it already leaked, but they don't make any noise)
• shop that road-force balanced everything said there was indeed some kind of rotational vibration behind the rotor (didn't do further diagnosis on that)

If you've made it this far, I owe you a beer.

Basically I'm at the end of my rope for trying to figure this out. I could go and replace the ball joints again sure, and I may end up doing that anyhow for track usage and my own sanity, but this problem preceded those in the first place, and they didn't make a difference (although the steering is awesomely sharp now). I've never had the transfer case inspected inside, but as I understand it there are two inner driveshafts in there. Not sure if they could affect steering though.

Maybe running a wider tire isn't helping, and maybe the neg camber isn't either. Maybe my xfer case is borked, sending different torque side to side? Maybe it's the wheels, the tires, the rotors, stuck caliper piston... or maybe this is just an evo long-life fact and I have to live with it. Maybe it's all of the above. The CA Bay Area has the worst roads I've ever experienced.

I'm just hoping this community of years of expertise can step in and offer me some ideas to explore. Please feel free to ask me questions about anything, and I try to get pictures for you if need be (though I don't have regular access to a lift). Tell me about your experiences and what you went through as well, maybe I can learn from you. I'm looking for your ideas for sure.

My next move is to check the rotors for uneven heat left-to-right to see if I have a dragging caliper piston (thanks for the tip smike!). However we don't see uneven wear in the pads, nor do I see uneven wear around the rotors.

Thanks all, apologies for the length.

 

Just throwing it out there is there any possibility that the whole wheel itself is bent, in my Jetta I had countless alignments, balancing, and suspension components replaced like you've done no where near the extent of you but never got the vibration away. Bought new wheels and when I had everything re-aligned and balanced it never vibrated again

 

Great suggestion, and I have considered this. The only thing is, would the vibration come and go like it does if I had a bent wheel? I guess the answer is, maybe, depending on how bad the bend is.

I haven't yet tried another set of wheels/tires, but that could be an easy step to take to see if that's the issue. FWIW the shop that did my RF balancing said the wheels were fine and that the wheels+tires were perfectly true and straight after balancing.

Over the lifetime of the car I've had 3 wheels replaced so they're not all the same age (but they are all oem enkeis).

 

Yeah that's what comes to mind when I read everything. Guys who did my balancing said it was fine but I noticed the wheel that was bent had a lot more weights which led me to switching them I only got vibration going 70-85 if I did over or under it was fine. Or maybe since there all different wheels the weights off? Just trying to think outside the box you've done everything logical so far lol

 

You're a good man, and thorough.

I think I'll take your suggestion to my shop and see what they can do they have plenty of wheels and tires laying around to try. Thanks man.

 

I may be way off here, but, when I started dating my wife back in the day she had a car she named, "Shakes."

She's such a dork, but cute anyway.

After driving her car and discovering that the darn thing shook around turns at speed, sharp or minor, I took a look. One motor mount was busted clean off and another wasn't that far along in this world. She'd been driving that way for a while.

Sorry if you mentioned motor mounts, I did read the whole thing, but forgot some of it. Good luck.

 

when you got road force balanced, did you by chance happen to get the road force lbs? This is the spec that shows if it needs road force matching to correct the balance of the wheel and tire assembly. Sometimes you can match the assembly and get it in spec, but still have an rather large road force (measured in lbs). If its in the green that still doesn't guarantee a non vibrating assembly. It may still have a out of round tire or bent wheel. Also check your tires for any abnormal wear.

Have you tried swapping the front wheels to the back to see if there is any change?

 

You can try borrowing a relative's set of 5x114 wheels and see if there are any differences. Or you can try the 'ghetto way' and use the spare tire and keep swapping each tire out for a test drive and see if there are any significant changes.

Working at Walmart TLE, a bent rim is very common for highway shakes and does not truly balance a wheel even if the machine shows that it is.

 

Quote of the day, that's hilarious. lol

 

Could be a bent wheel or messed up caster bushings.

What was the caster reading after alignment?

 

I would consider a bent rim or material inside of a tire such as fix a flat or rubber. How do your tread patterns look on the tires? Any signs of odd wear or chunks missing?

I have a KCA395 Kit for sale if you want to do those ball joints.

 

besides the bent rim or out of round one, this is going to seem random but bear with me lol the roads that you drive on, does this occur only on concrete? or asphalt as well? Here in my state of south dakota, they cut the interstate drain groves with the lane instead of across, so with my nittos i get tire vibration at random speeds. they go away around 90ish idk just a thought

 

Ever look at motor mounts? Trans mount?
What comes to mind first for me is a broken mount, or possibly solid mounts?

How does the car steer after the new rack and pinion?
Possible there is something wrong with the system.

If its Rpm variable, Does the car have a balance shaft? If it does maybe its possible that is out of sync.

 

Switch rear wheels with front wheels, if interior shaking persists but not on the steering anymore then is a wheel tire issue. see if there is any end play by moving the tire.

If possible decrease camber and increase caster, that will provide more negative camber during curves, but less negative camber during straight driving. what´s the caster and toe on the front?

Do you hear a clicking noise apart from the tire squeal? might be a damaged bearing.

Did you tighten the cv shaft nut to spec, check/retighten after 1k miles?

I've seen assemblies of axles (I do axle engineering for a living) going bad on nvh just because there is a paint mark or score on the hub, then the stack up goes to hell and the wheel vibrates like crazy. check for a sticker id in the rotors, you may have missed that as well.

can you provide a video of the issue if possible?

 

I say tires. I had some Goodyears that were like you describe but not as bad. They were mounted and balanced by the same outfit that does all my tire work and everything else was always fine. I could sometimes drive for twenty miles with a smooth ride and then the shakes would start. After a few miles - smooth ride again. Well, it made long car trips less boring.