hetman

I believe it is the surface variation as an object rotates. So for example to check if you have warped disks you measure the runout, a lot of runout means warped disks and hence shuddering.

So I thought I'd do a bit of an update. I've had this looked at by a vehicle inspection joint. They seem to have found the problem: runout on the axle flange (wheel flange? I thought there were no axles on the front). I've had the car for a few weeks now and had a chance to push it a bit and there has been no recurrance of the shudder. You'd think 4 other mechanics would be able to figure this out :-/ Thanks again for the feedback!

I've bedded them my self on a few occasions (no stopping until cool again and all that), let the mechanic bed them other times, etc etc. Never seems to make a difference either way. The calipers have been checked by a couple mechs who reckon pressure is even on all of them. The runout's been checked, although on the last two occasions the first time the runout was apparently within tolerance, and the second time it was not. Shudder seemed just as bad in both cases. And strangely the shuddering seems to randomly get better and worse (which if my damaged disk theory was true I would've attributed to the angular displacement between the two front wheels, i.e. how the carbon hardened blobs lign up... I know seriously stretching for any kind of explanation here). Good question with which rotor is warping, I forgot to mention that last time I had it checked although I can only assume if it was only one they would've told me (or not). It seems the last mechanic I had look at this decided he couldn't make any more money out of me and lost interest in actually troubleshooting this any further. That's why recommendations for someone with decent persistence and experience with this sort of thing would be great. Cheers guys

Hi guys. I'm after a bit of input on your experience with warped disks, I can't seem to get a straight story out of any mechanics (though most are usually keen for a dollar). Any suggestions or recommendations for a mechanic that might be equipped to deal with this would be awesome. I have an R33 GTS-t with the standard 4 pot calipers. Haven't had an opportunity to track it, so while there are some nice roads out of the city for spirited driving, obviously there's only so hard you can push it. Until recently I've probably braked pretty hard even in normal traffic because of annoying squeel from the fronts. Originally my disk warping problems started with a set of slotted RDA's together with some PBR performance pads. Warped after a couple months. From then on these would hold on for maybe 2 weeks if machined, and then the shudder would slowly creep back. During this time I had a problem in the steering rack fixed which had a bit of play when warm, a wheel bearing and stub axle bearing replaced, all on the right side. Since then no one has been able to fault the suspension since I presume what remains is a brake heating issue. Eventually I had the disks replaced with original Nissan rotors and pads downgraded to Bendix Heavy Duty. Of course, it didn't fix the problem. After a while these rotors started to go as well, the killing blow being a nice drive through some mountains... the disks badly warped as a result (in retrospect those Bendix pads probably weren't so good for those rotors... there didn't seem to be any fade when hot). Anyway, no amount of machining seems to get these disks good now. At best it reduces the shudder which then returns in full force over the next few days!! I've downgraded to a Maxi pad but that seems to make no difference (at least this guy managed to finally shut the squeel up with some shims & grease). I understand cast iron disks if seriously stressed tend to result in patches hardening due to uneven carbon content so it's likely these disks are fubared now anyway. This is consistent with the uneven grabbing I get from the at low speeds (30km/h and below) which doesn't seem to be coming from the back given that's been recently worked on. I presume if I upgrade to some DBA 5000 this might finally make my issues go away, but I'd like some advice before I pour more money into this. Cheers

I guess that's not the problem then. My whirring noise is only there when the clutch is engaged (foot off the pedal). It goes away when I depress the pedal though. (You only really hear it distinctly in neutral though since there's a lot more noise from everything when accelerating).

Oh one more thing, grey pearl mentioned something about clutch noise. I did also get a Exedy Heavy Duty Organic clutch put in when I had the reco done, but that's not a twin plate so I guess it shouldn't be contributing to the noise?

Yeh, R&R included. Apparently they replaced the bearings but I'll have to look into it further.

Thanks for the suggestions. The oil making the synchros slip might explain why the gear changes are quite smooth if you give them a little time like I mentioned. I'll have to try another oil. For those interested the job cost $1500

Hey Guys, I had the gearbox reconditioned in my R33 gtst recently. It used to have problems crunching going into 4th and 5th if you didn't let the revs drop and this was fixed which I'm pretty happy about. There's still a few things that are bothering me though which didn't really improve: - Still a bit notchy if you shift quickly. Much better if you give it a half second before pushing through. - Used to be a bit noisy when idling in neutral. Now it's a lot more noisy (especially noticeable from the outside). The guy that did the recondition claims the gears don't mesh very precisely on these boxes and hence the noise. - Sometimes won't go into reverse. After you blip the clutch goes in ok. I have the redline lightweight shockproof oil in it now. I guess what I'd like to know is whether all these sound normal for this gearbox. Should the recondition have made a bigger difference? Cheers

Cheers mate, they look a lot better than the old worn crap

G'day. If you still have any of these spare I'd love to get a set. PM details. Cheers

Hi guys, I've been wondering about how noticeable tyre roll is with the stock rims/tyres on the R33 and how much better it is with 17" rims. Right now I'm running the stock rims with 225/45R16 (I know, yuck), I've been thiking about either putting some 205/55R16 on there for a while or going straight to the 17" rims. I wanted to know if there'd be a noticeable difference from my current set to the stock tyres. Also, anyone that's upgraded from 16" to 17" rims, how have you found the handling of the tyres changed? Finally, if anyone has any recommendations for tyres that grip well but sacrifice longevity for lower price I'd love to hear 'em. Cheers