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MG MGF Technical - Rear discs corroded

I have just taken my 96 F into the local MG Rover dealer (Chelmsford) to have the suspension raised up a little and have the tracking done. They have just pointed out that the rear discs are corroded quite badly and the discs glazed. Is this something that is common ? They are asking for GBP 264 to replace these; is that reasonable.

I have no previous experience of this dealer but am already a little suspicious on the basis that the suspension was adjusted and tracking altered in a little over an hour !!!!! What happened to the 2 hours settling time ?

Any thoughts anyone ?

andrew northcott

Andrew - one of my rear discs is showing signs of corrosion & pitting on inside face - easilly seen if you crawl under neath (easier still on a ramp)
I believe Rog has noted that most rear brakes are only along for the ride and parking.
Corrosion and seizure, esp of handbrake mechanisms is pretty common across lots of makes.
I have now made a mental note to try to remember to regularly exercise the rear brakes by pulling handbrake on/off several times - when cruising on a nice strainght empty bit of road.
For your money any garage should replace both rear discs and pads.
It's not rocket science, if you have reasonable skills and decent socket/spanner set you could diy.
I aim to do my own when I get round to it.
I'd advise you get a quote from Lucas Autocentre or similar outfit who ought to be able to beat 264 'cos the Dealer's price will includes inflated Rover parts costs
(Repair time is ~ 1hr labour)

When you say the "suspension was adjusted and tracking altered in a little over an hour" do you mean 1hr elapsed time from drop off to pick up - or you were expecting to be charged for settling time? :-)


ps re trac
John Thomas

Re suspension - I was just suprised that the dealer did not allow for settling time. From what I have read on this BBS when the hight on a hyragas system is altered, a 2 your settling time is needed prior to the work being done. They seem to have done the hydragas and the tracking in about an hour. Still, they're the mg specialist so they must know what is right.

Thanks for your comments on the discs. I agree I think I need to look at alternatives, and to be fair to the Rover dealer, they did tell me that the regular garage where I have the servicing done (non Rover dealer)may be cheaper than them for such a job. I just used the MG dealer this time because they seem to be the only guys with a hydragas pump round my way.

andrew northcott

I agree- one hour is not long enough to set the suspension height. Whilst I have not found that it is strictly necessary to allow the car to settle before altering ride height, I know that if you are altering the hydragas pressure to get a particular height, the first height you set is not the one the suspension ends up at... in other words, to get the ride height equal and 'just right' takes time and perservence!

Regarding glazing of the rear discs- its nothing that a couple of 'emergency brakes' won't shift. Same applies to surface rust- unless there is pitting as John mentions.

Funnily enough, I find that the rear brakes on my car do a fair bit of work, judging by the quantities of brake dust covering the wheels. The braking balance feels absolutely fine, and no preponsity for the fronts to lock unless under low grip situations and very severe braking. Braking (performance and balance) has been improved since I fitted 'those' tyres (the S-02s)... Hmm, I wonder... Coincidence?

Rob Bell

Had my front discs and pads changed a couple of months back by a Lucas brake fitter at my local tyre centre. They did the job for 130 (inc. VAT , parts & labour) and a one year guarantee!

It's worth noting that brake discs do rust but that doesn't mean they're always corroded.

My front discs had corroded, and were a MOT failure; they were apparently badly pitted. My May '96 F is treated well and kept in a garage, and rarely put away wet. Thats mainly the effect of winter condensation and sweating I guess. Cost me a new set of disks and pads. I've not had a problem with my Rover 200 in ten years, but it is driven every day.

Perhaps as John suggests, brakes do need to be worked hard to keep them in good nick.
Rob Speare

Very interesting comments. Without seeing the discs for my self I cannot see what their definition of 'coroded' is but the only other comment was the pads 'were servicable but glazed' and I assume they were considering 'roughing them up' to use on new discs.

I think I have to find out exactly how coroded they are. My car is always garaged and not used in the wet that often anyway. Maybe a couple of emergency stops will help.

I also had SO2s fitted to the back last week and have to agree that they really make a difference.

My main concern when I pick up the car tonight is that with suspension being adjusted, I have a car looking like a Freelander. I did tell the garage not to set the ride hight at more than 360 though.
andrew northcott

This thread was discussed on 26/10/2000

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