Brake disc life
Seventeen months ago, on the advice of my local Toyota dealer, I had new discs and pads fitted all round to my 2002 Toyota Corolla Verso automatic. I now think that the front discs have warped as the steering wheel shakes when braking from speed. Toyota has informed me that the brake discs only have a 12-month warranty. Does this seem reasonable? I have done 13,000 miles since they were replaced and do not drive fast – mainly shopping trips, with one journey to Cornwall each year and one 100-mile round trip each week.
Second, occasionally I find a light film around the edge of the passenger airbag lid. It wipes off easily and does not return for some weeks. Any suggestions as to what it could be?
And third, I had an advisory at the last MOT that the brake pipes running from the front of the vehicle to the back had surface corrosion. Can I give them a rub down with wet-and-dry, give them a coating of Kurust and then a coat of Hammerite, and would any of these actions give me a problem at the next MOT?
Geoff Allen
The shaking you describe does sound like the effect of warped brake discs. Unfortunately, it is very hard for the manufacturer to place any warranty longer than 12 months on parts that are so susceptible to damage from various different usage scenarios.
Many years ago, I was involved in trying to determine why the discs on a Vauxhall Omega were constantly warping. Three sets of discs were replaced and all ended up the same after less than 6000 miles. The discs were professionally fitted using a dial test indicator and it took a while before it was discovered that one of the front road wheels was distorted. This was causing the disc to be unevenly clamped into position.
As 13,000 miles is not a lot for a set of discs, if you do have them replaced then I would ask the garage to check the disc run-out with the road wheel fitted. This is tricky but worth the effort. However, the problem may not necessarily be the discs – I would inspect the track rod ends and suspension joints to ensure there is no excess play in any of these components.
The light film you find around the airbag housing is most probably just silicone deposits from the edge of the housing. The silicone lubricant ensures that, should the airbag deploy, it will open without friction.
Regarding the corroded brake pipes, as the note was only an advisory, I would imagine that the pipes are only suffering from very light corrosion. Painting with Hammerite may prevent rust, but there’s a danger it may also cover up further corrosion which occurs to the pipes. I would give the pipes a clean with nothing harsher than a scouring pad, then coat them with grease. This should prevent further corrosion forming, but will not hide any serious or potentially dangerous rust which could occur under a painted surface.
I must add that it still surprises me that manufacturers continue to use steel brake pipes with a limited life when excellent cupronickel pipes are readily available for the aftermarket.