Wondered if anyone could help me out, I have serious steering wheel wobble under braking and I;ve only just (1month ago) fitted new Godspeed discs! I did the following checks;

4 wheels fully balanced

this didn't solve the prob so I had the steering checked out and wheel play, no play left to right, no play vertically on each wheel, track rod ends no play, ball joint no play, no play in steering rack.

SO...I had it put on a 2wd rolling road (with clutch held in), and they powered the front left wheel and I applied the brakes with consistent force...the needle went up and down rather than maintaining steady braking force....right wheel stayed bang on level with constant braking applied...?

Does this mean the left hand disc is warped? They are new Godspeed discs only 1 month old and they haven't been worked hard at all!

My last set of discs did the same kinda thing so I thought ah I'll replace the warped discs...but now it's doing the same...I suppose my question is this:

What's the chances of Godspeed providing me with a new warped disc.

or

Could the discs be ok but something else is making the whole lot wobble under braking, can the caliper be warped or can the disc be fitted badly causing to wobble? Or can hub carrier be bent?? Much confusion and sadness

Spence

 

Spence,
I too am a user of 'Godspeed'brakes, however, mine are of the disc and bell variety, which are yours?
Ron
(very happy with my brakes)

 

Spence, have your new discs always been like this? If so, maybe they weren't fitted properly.

I'm thinking that if you don't clean all the rust and crud off the mounting face, the disc doesn't sit true. This would feel like the discs were warped.

Also, it's unusual for just one disc to warp, and if they are the alloy bell variety you'd have to give them some serious abuse.

I can only think this is either a fitting problem or a manufacturing fault.

Richard.

 

Spence , The chances of us supplying you a warped discs is non existence , I make the discs and bells myself and they are as true as a discs can be , I am very carefull of this , It could be either muck or rust on the hub face , you should allways clean these off with WD40 and emery cloth before fitting new discs to make sure the surface is perfectly clean , It could also be a warped hub if it was doing it before , Clean off the drive flange and if this doesn't cure it if you want to take the drive flange off and send it to me I will skim it F.O.C. ,
Our discs are covered by a 12 month guarantee so in the unlikely event of the discs being at fault we will change them , Hope this helps , Ian

 

I saw an interesting post the other day from a chap who reckons that if you do get warped discs once, then you need to check the wheel bearing run out for play, otherwise the warping will come back again and again....

Funny that because it happened to me on a cavalier once where I tried all sorts of different discs, even cleaning the surfaces as Ian says but the problem remained. I didn't get to check the bearings.

Be careful running with warped disc for too long, it shagged my stearing rack seals and cost me a packet to fix. Also when running in new discs, be careful not to keep your foot on the breaks when stationary as this causes a hot spot.

F

 

I have the very same problem with my 94 Legacy GT (TT)

When i bought it a month ago i test drove it and told them to replace all four discs - which they did....

...with cheapy ones (Blueprint)....which i had the same warping occur after 3000 miles!

Have just bought Black Diamond Combi's and they are new on yesterday and i can feel a slight pulsing at 70 / 80 mph braking speeds!

The run out was checked both times and nothing appears to be even slightly out of true....

I'm wondering whether it may be duff tyres as there are a large number of balance weights all in one place. Could it be distorted beading in the tyre?

Last thing i want is to shaft my new discs!

 

I did manage to cure my warped disc problem in the end. I took the latest set of brembo disc that had warped and got them skimmed for £10. The problem dissapeared, I guessed at the time that all the heat warping had occured, which I then removed with a skim. Most engineering workshops should be able to do it for you.

Try it on an old set of discs but try to keep them on the original sides of the car just in case.

F

 

cheers for all the advice guys. Ron, they're single piece discs by the way...

Hoppy yeh well the brakes have kind of always been like it. I had old discs on and they wobbled alot under heavy braking, so I assumed it was the discs so I replaced them. At the same time as I fitted new discs I also had a new wheel bearing fitted cos it was noisy as hell.

Thing is they seemed ok for a while after I'd had them fitted, probably because I was taking it easy because of bedding in like. Anyway, it just got worse and worse!

I've heard it's difficult to fit a wheel bearing wrongly though? I mean the wobbling was there with the old bearing, but it's actually worse now with the new bearing and new discs !

So basically I need a new/skimmed hub face, and probably the disc needs a skim as well, and the bearing re-aligned if this possible? Hope I haven't damaged the new wheel bearing ! Anyone got any second hand hub faces? All I've found is complete hubs for £100! Might have to check out new hub face prices.

Ian, cheers for the mail, didn't mean to question the quality of your discs, I kind of knew it wasn't them, but it was always a possibility and you know what it's like when you're trying to troubleshoot a problem like this! Very Very annoying!

ok so a new/reskimmed hub face and skimmed disc. Ian where abouts are you? I could drive to your workshop and get the disc skimmed so I don't have to take the car off the road if that's ok?

Spence

 

oh yeh the hub face was clean had that checked t'other day

cheers

 

Interesting that you mention this, as I have just noticed this on mine. I fitted Ians kit about 3 months ago and have done very little miles since, but enough to run them in.

I must admit that they have been very good, and the few demo runs i have done for friends, where the car triggers the abs at about 90mph and then pulls up straight and very fast have been impressive.

However I too have noticed a slight wobble on the front, but it only seems to be when warmed up, I cant feel it all the time. Also it only seems to happen from higher speeds, like over 40mph, so I cant feel it in town.

Unfortunately I have not been able to investigate this properly, as there is so much it could be, like bearings, hub face, CV?, etc one thing to note was that I twatted a kerb broadside very hard with both left hand wheels (18s) and have maybe pulled something out of whack. Cant remember if i had the wobble before or not.

Anyway, I imagine that by the time i pull everything apart, take the disks off, put a straight rule on the disks, find they are fine, then reassemble everything the problem will go. Or does the heating up factor point to something else?

Gareth

 

Yeh not sure about that Gareth. Fact they are new discs should in theory mean that they are ok. It seems that things like hub faces can be dirty and cause it or they can be warped themselves. I think I'm just going to invest in a new entire hub assembly, because i can't find a hub face only, not sure how much subaru charge. I can get a 2nd hand entire hub assy for £100 though (from scoobyimportparts website) - so i might try that.

 

Floyd nice one I think I'll get the disc skimmed as well.

Don't understand this wheel bearing 'run out' though, I thought they were pressed into the hub with a tight interference fit, and basically couldn't move. Obviously not I guess!

Wonder if my bearing is damaged then? It's a new bearing as well in that side. Damn.

I dunno I hope getting a new hub assy sorts it all out.