Shuddering/vibration At Speed, quickly running out of patience..

[Bry]

So as you guys know I've been pretty meticulous in cleaning up my Altezza to the point where I'm happy with it.

I'm not sure if I only noticed this issue after replacing a bunch of suspension parts, or if that just made it more prevalent. I've spent more than I wanted to in the hope of getting it riding nice and smooth, and I'm really starting to lose my patience..

At highway speeds (80-100+km) there is a rather unsettling shuddering and vibration from the front/middle of the car.. almost as if I had a loose wheel or dead balljoint. It is even noticeable at 20-60km like a loud diff whining/wheel bearing type noise. When heavy breaking (ie. heel toeing) there is pulsating in the pedal (not abs). A little difficult to explain.. but it makes me hate driving the car at the moment - don't want to aimlessly replace parts, so before I take it to a suspension specialist thought I'd ask for opinons.

Relevant Parts replaced:
Engine oil: Castrol Edge 5w-30
Diff oil: Castrol SAF-XA
GBox oil: Redline MT90
New TRD Castor Arm Bushes
New Front Lower & Upper Balljoints
New Front Swaybar Links
New Tie Rod Ends
New Tyres - 215/45/17 Federal 595SS
New BC BR Coilovers
New Ikeya Formula Rear LCA's
New FIGS Rear toe arms
Wheels replaced with known good ones
Wheel Alignment & Balance

My thoughts
1. Wheel bearings - All feel good, however rear left has very slight side to side movement

2. Brake Rotors warped - Came with Slotted/drilled so this is a possibility. Though problem occurs at low speed as well as highway AND braking.

3. Tailshaft center bush/bearing

4. Diff bearings - Oil was low when i changed it, due to leaking axle seals

5. Sticking caliper - Haven't checked this yet..

Ideas/things to check please?!

[mlcoolj]

I would start with the rotors

[will02]

yeah i would say start with replacing the rotors.. by far the most common fix for those kind of issues.

I had similar vibrations when i first purchased my car. Had the rotors replaced and problem gone.

Do both front and rear.

[Bry]

Luckily I've never had these kind of issues in the past so I'm not too familiar with the fixes. Is there an easy way to check disc runout without a micrometer/dial gauge? If this is the culprit (I wish) would machining them not fix it or are they destined for the bin?

Just a shame to throw out near new slotted and drilled rotors and spend $400+ on a net set...

If my calipers are seized and need a rebuild then I was considering a BBK lol....

[will02]

Personally wouldnt know an easy way to check, I went and got them checked at my mechanic and there was slight warp on mainly front and slight at the rear.

Would say give machining them a go. If the rotors still have plenty left dosnt seem wise to get a new set.

[greeneyes]

Check the rims too, as balance is not everything.

Jack the suspension so the wheel is a few mm off the ground, then put a screwdriver on a paint tin or some stable block the puts the screwdriver blade against the machined outer edge of the rim.

Spin slowly and watch the gap come and go. Keep an eye on the edge of the tyre too, a fault in a tyre wall can make the tread wobble. Check inside and outside rims.

You could do the same with the discs, take a wheel off and use a couple of nuts to fix the disc on again, then spin against a screwdriver. I've never had to do that, so I don't know if you will see a significant amount of runout, it might be less than a mm that is important.

[peanut]

if there is a slight warp in the disc you should be able to detect it by:
find a stretch slightly downhill road. while the car is rolling press on the brake a little. as your car is rolling slowly, if the disc is warped you'll feel the car jerking. it's hard to explain but I always feel it when the disc is slightly warp when i almost come to a stop at the lights.

if you feel the padel is vibrating under braking then you have a very warpped disc.

but if you feel the vibration without braking then i recommend you check your hub bearing

[Tezz-Winnie]

Check your calliper pins too. I have replaced a couple from poor maintenance from previous owners. They get seized and dirty and cause one side of the pad to wear quicker then the other and they bite randomly causing bad vibrations. Thats what my issue was anyway when I first bought my Altezza.

My list to check would be
Calliper pins
Rotors
Wheels
Wheel bearings(you would know if these were gone though!)

[Bry]

Just checked front caliper pins, few were a little hard to move.. definitely not seized though. Cleaned and regreased them all. Caliper pistons have a little surface rust but move in and out freely with vice grips.. pad wear is also nothing unusual.

Front wheel bearings seem fine.. no movement from the usual testing.

Wheels/tyres are fine on my other car so we can rule them out.

Rotors - may pay to get them machined...

Will check out the rear tonight if I get a chance

[Tezz-Winnie]

If the wheels were buggered you would feel the vibration through the steering wheel at high speeds. If the rotors were warped you would feel them through the pedal.

[Bry]

Slight improvement after greasing front slide pins.

Steering wheel isn't really shaking.. Can feel more noise and vibration through pedal and chassis.. Above the typical drivetrain noise. Not too noticeable under hard breaking either.

Almost feels like axles or tail shaft is to blame, definitely feels rotational in nature. Might pay a visit to my driveshaft shop for them to check it out.

[Tezz-Winnie]

This was the exact symptoms I was suffering from before changing my pins, boots and screws. What sort of grease did you use? If you just use any grease they will eventually seize.

My money is on a warped disk. More then likely to be the rears from heavy braking then using the handbrake to park.

[Bry]

Used anti-seize lithium grease type stuff.

Interesting.. I'll check out the rears tonight. May see about getting them machined before I blame axles then - argh I hate this so much!

[Tezz-Winnie]

Lithium base grease is a no no. Try Silicone based grease...

[Bry]

Sorry was thinking of something else - I use the permatex
Anti-seize.. Believe it's graphite based.

[Tezz-Winnie]

Ahh that brand is great I use the Brake Parts lube. Are you sure its graphite based? Most of their lubes are copper based, a step better then silicone based lubes but cost to much to justify unless you see track time or your having lots of issues r you have it just lying around lol.

Aside from your rotors, at least you have your brakes sorted. Just roll into any brake shop and get them to check your disks for deformation, make sure you slip quote in there somewhere so they dont charge you for the pleasure

[Bry]

Yep it's this one - http://www.permatex.com/products/automotiv...Lubricant_a.htm

Yeh will try drop in somewhere near work, such a hassle getting work done that I can't do at home!

[jeremyflower]

I had a brake rotor that was warped enough to almost send me off the side of the road under braking, turns out it was only warped by 0.006".

It's worth getting your rotors skimmed anyway.

[Bry]

Taking it into advantage suspension in the morning to see if they can pinpoint the problem rather than me aimlessly replacing stuff.

[Bry]

Cars in the shop now.. after a quick drive has been isolated to the rear of car (knew this already), doesn't think diff.. leaning towards wheel bearings or possibly axles. He did just say it did sound a bit like just tyre noise and the rosejoints in aftermarket arms may be amplifying it - i really hope that's not the case because it sounds and feels worse than my race s14 with solid mounted/rose jointed everything!

He's gonna check it out and let me know anyway.

[mlcoolj]

any news?

[Bry]

Rear wheel bearings, possibly driveshafts too. Ordered bearings from Nick, will take it back to get it done next week when they arrive.

Front bearings possibly slightly noisy, replacement not necessary yet though. Will see how rears go first since it's costing 100-150 a corner in labour... at least he'll do the diff side seals for me at the same time since I cbf!

[mlcoolj]

ok man, keep us posted!