High speed shudder
Hi Guys.
I got my new wheels fitted a few months back (17" with cheapo zetum tyres)
I had them balanced from bob janes when I bought them but it didn't really feel right around town and at 110km/h on the freeway the wheel was shuddering like crazy.
So I took it to bridgestones near my place and paid to get it rebalanced again, they said bob janes had done a crap job and they had fixed it.
But its still shuddering just as bad at 110 like the wheels were never balanced in the first place.
I have a 1200km round trip coming up next weekend all sitting at high speeds and would like to get this fixed before I go for safety and comfort.
Anyone know what could be causing this, its been balanced three times now and still no difference....I have jacked the car up and no play in the wheels so its not tie rod ends.
Car is a 96 VS live axle on Superlows and monroe GT gas shocks
Exhaust Guru
^^^ That will most likely be your problem.Originally Posted by someguy360
Put some different wheels on your car and take it for a test drive. If it still shutters with different wheels then check all your bushes and wheel allignment.
Don't have any spare wheels, but will check over all the bushes....I did replace them all within the last 6 months.
Don't know if its the cheap tyres as I have had them on previous cars and a couple of mates with commodores have the same ones and they are ok too
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Hello Someguy, if its not the new tyres maybe check to see if one or more of your brake discs is bent slightly and not running (spinning) true.
EDIT - Thats only if its happening whilst braking.
Last edited by VT_SS; 09-02-2012 at 06:18 PM.
did you change your castor bushes? If your control arm has any movement in it, it can wobble when you get up some speed.
All bushes are good, had it up on the hoist and went over everything on the weekend (there is a bit of wear/play in the rear lower control arms but the shudder definitely feels front end related)
The shudder seems to be occuring at low speeds too (60,70 when cruising in 4th) and also when braking......then gets particularly bad between 100-120km/h
The only thing left to try is the tyres so I have a mate bringing a set of stockies with RE92's down tonight to test and see if it makes any difference.
Exhaust Guru
Ahhhh...more info comes to light.
The shuddering under brakes will be warped rotors. Sometimes this can cause a high speed vibration as well.
Well its not happening just under high speed anymore.....its also just cruising at 60 its not really noticeable at that speed unless your paying attention but its still there
Exhaust Guru
See what happens when you change the wheels over.
Why is nobody asking if the correct wheel spacers are fitted to the hubs?
Didn't even know I needed any spacers
Real cars are steel cars.
No matter how much you balance the tyres they need to be round to prevent vibration.
You get what you pay for.
If I told you I was a compulsive liar, would you believe me?
yup, cheap nasty rotors that are warped because they are crap! can indeed be unbalanced and cause vibration. you will be surprised at how many brands of rotors are not balanced. I bought Brembo under the IBS brand name and these were clearly balanced as you could see where they had machined out some metal at the edge and the other side rotor had a counter weight clipped in one of the vents.
Great rotors in fact the best I have usedno cracking, no warping, balanced and I have flogged the absolute shit out of them for well over 60k so far and still nothing wrong with them except a fair bit of metal is gone, but that's just me driving
my last set of rotors did vibrate a little at high speed.
Its possible that its your brake rotors as mentioned, but, that said, my mates VZ had a wheel come off at 80km/h and naturally he hit the brakes and the car landed on the rotor which was locked up and has put a huge flat spot on it. Its taken off about a 1/3 of the rotor on one part but it doesnt vibrate or even shudder under brakes, which is pretty amazing, even more amazing is that he still hasnt fixed it and it still passed a roadworthy lol.
Also could check if your axles are straight too.
Thanks guys, just remember this problem isn't only apparent during braking, lots are jumping to brakes right away, the problem is almost as evident when cruising (even at low speeds such as 60)
I put a set of stockies with toyo tyres on the front, made no difference.....trying the rear tomorrow.
Only things left that haven't been replaced are front and rear lower control arm bushes, the fronts seem ok, a tiny ammount of play when attacked with a crowbar and the rears aren't great but it still feels more front end related......every other bush has been replaced
If the rotors are indeed warped would I notice that when I am driving, the problem is just as apparent with my foot on the accelerator.
Could it be bad front shocks, the rears were replaced with monroe GT's when I lowered the car but the fronts are still original (date stamped 1997), could worn shocks cause these symptoms?
Obviously Unsensible
regarding warped rotors (i am aorta getting a similar problem but it goes away and comes back when driving)
how can you tell if they are warped?
i did take all weight off the wheel once and was spinning it and every once around it would have tge rotor on pad noise. but not enough to slow it down.
would that be them because they are warped?
how about we make the pedals out of sticky rubber and the shoes with steel spikes. at least my shins would like that
Ok so tested stockies on the front, still the same
tested them on the rear...still the same
Got it back off the ground today.....all front end bushes have been replaced with fresh nolathane bushes which are tight as a drum.....exept the front control arm bushes which look like this
They have a little bit of play when attacked with a crow bar.....could this be my issue.
I also had a look at my link pin bushes, do they look to be installed correctly? they don't look like they are sitting properly to me (should there be that gap between them?)
Other than that i'm not sure what it could be other than rotors which is wierd as the problem occurs while driving and not just braking
Real cars are steel cars.
Did you try four stockies at the same time?
If I told you I was a compulsive liar, would you believe me?
no did the fronts....noticed no difference then did the rears noticed no difference.
so all 4 wheels were swapped at different times to eliminate a flat spot in one of the tyres etc.
I'm thinking its fairly safe to say is the front inner control arm bushes.....they have play in them and after some more in depth searching others have had the same symptoms and replacing them was the key.
Car is booked in with the mechanic to get some work on the exhaust done this week so will get them to press some new bushes in and see if that fixes it
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I had this problem and it ended up being warped rotors. It was also noticeable whilst I was just cruising around, i would certainly look into it.
Yeah, well the bushes are still due to be replaced so I will do them while I have access to the press
I will also machine the rotors while I am there.
wow! a lot of people threw opinions at you mate, did you find the problem?
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