Brake Discs minimum thickness

steadynerve

Hi I just had my brakes tested at kwik fut (free service) they show that the fromt pads are fine but the front discs are sllighly below manufacturers minimum thickmess.

Kwik fit are saying replace the discs and this also means replacing the pads. However a quick check of my haynes manual and it says you can run one lot of pads down first and then replace the dsics if they disc in between goes lower than the mimummum thickness/

Apparently discs can be resurfaced above the minimum thickness but not below it. But clearly if you have the disc resufraced just above the minimum thicknesss you would be looking to wear out the brake pads out first.

Does anyone know if the manufacturers minimum thciness recoomedations have tolerance in them to allw the current pads to be worn down first (if fitted before discs below minimum). so that discs and pads can all be repaced when the pads need replacing.?

I think they must else they would specify a higher thickness for having discs resurfaced? i think all the stuff on the net about replacing as soon as reach minium thickness is jsut sales speak. obvisoulsy you musn't fit new pads if below the minimum but surely the guidleline only works if the minimum thickness also allows tolerance for the pads currently on the car to finish there life?

When answering if you can provide a source that would be great.

skiddlydiddly

Discs should last longer than pads.There is a stamp pumnched into the edge of the disc to show when they are getting too low.

To get them skimmed will prob cost £5-10 a disc so if they are on a popular car like a Fiesta which you can get cheap replacements for I'd just get new ones if they are bad.

steadynerve

The discs are fine apart from the thickness being below the manufacturers recommended minimum thickness. But does anyone kow if the manufacturer buidls in tolerances to allow the discs to be used until the current pads need replacing. This it what the haynes manual seems to suggest and i trust his more than a kwik fit or any other salesman?!!

(Obviosuly when the disc cracks or so signs of excessive heat then it needs replacing. But this is not the case).

So presumably if would be ok to check them say every six months for sign s of excessivce wear but keep them going until the pads need replacing.

BillTrac

Sorry, you went to Thik Fit and believed them?

Speak to a local stealership, or an independant. Do not listen to Thik Fit

skiddlydiddly

Well bear in mind that the thickness of the disc also relates to its ability to dissipate heat.A thinner disc is goint to heat up quicker so you might risk brake fade.

Personally if its below what the manufacturers recommend I'd swap them regardless of whether Kwik-Fit-You-UP said.

cajef

steadynerve wrote: »

Kwik fit are saying replace the discs and this also means replacing the pads.

Surprise, surprise if you go to Kwik Fit for a free check you do not expect them to say nothing needed doing do you, they are infamous for doing work that is not necessary.

Gloomendoom

steadynerve wrote: »

The discs are fine apart from the thickness being below the manufacturers recommended minimum thickness.

Well they are not fine then! They are too thin.

The minimum thickness is just that. Any less and they need replacing (in pairs, and the pads too)

forgotmyname

Below the minimum is an instant MOT fail.

The brakes will still work, Just dont have a serious accident. If they have to inspect your car you will be guilty......

Hammyman

skiddlydiddly wrote: »

Discs should last longer than pads.

Not anymore since they got rid of asbestos pads and had to put in metal to get the same efficiency.

Hammyman

steadynerve wrote: »

The discs are fine apart from the thickness being below the manufacturers recommended minimum thickness. But does anyone kow if the manufacturer buidls in tolerances to allow the discs to be used until the current pads need replacing. This it what the haynes manual seems to suggest and i trust his more than a kwik fit or any other salesman?!!

(Obviosuly when the disc cracks or so signs of excessive heat then it needs replacing. But this is not the case).

So presumably if would be ok to check them say every six months for sign s of excessivce wear but keep them going until the pads need replacing.

No they don't build in 10,000 miles worth of tolerance. Secondly, thin discs are liable to crack under prolonged braking such as going down a 1 in 6 hill. Finally, they're the one thing that prevents you piling into a stationary object so scrimping on them is just plain madness.

somech

forgotmyname wrote: »

Below the minimum is an instant MOT fail.

The brakes will still work, Just dont have a serious accident. If they have to inspect your car you will be guilty......

they cant fail an mot unless they are excessivley worn/pitted (they cant measure them for an mot)

personally i would get a second opinion from a reputable garage