Disc brake pads - safe minimal thickness

Warren-Pat_01 · Guru

Disc brake pads - safe minimal thickness

Corndoggy · Senior Member

At 2mm I would be changing them tomorrow. And at130,000kms I'd be taking a close look at the disc itself.
These aren't the original pads?

Joda · Senior Member

I agree, put a new set on, especially towing, the van brakes help but the car does the bulk of the braking on the front brakes, are you doing them your self? A brake guy will probably want to machine the discs as well, disc wear varies from car make to car make, check the disc to see if there is a Ridge worn into the outer edge of the disc face where the pads sit, I check mine with a dial indicator to see if there is any run out in the disc (Wobble), Cheers, John.

Warren-Pat_01 · Guru

Thanks for your replies. In answer, yes the pads are originals - I tend to use engine compression where I can so I don't jump on the brakes every time when someone up front slows down. I checked both discs - they don't require machining. The independent mechanic is not going to be used again - I'll go back to one that I used with my previous two Patrols. I gave a friend the details of the independent mechanic & when contacted, this chap told my friend that if he didn't think the check was required, he wouldn't do it - not good when cars are under warranty! The next service will be done by the dealer as it will be the end of the warranty (six years) - but I will be checking how much oil they add to the engine - their record is not good - over filling by 0.5 to 1.5 litres! When challenged, they said it was ok because of fixed price services!!

TheHeaths · Guru

As a matter of interest, I am in SA, so checked minimum pad thickness requirement or guidance. I realise you live in Queensland, but under NSW roadworthy checks, 3mm is the minimum allowable.

Perhaps pad replacement would be a wise decision.

Warren-Pat_01 · Guru

Thanks Ian,
I should have been more aware of this geezza! He didn't even ask me what I was doing with the car ie occasional towing.
If I had a workshop manual, I'd do it myself but those things are rare now with only dealers getting them I've heard.

I have the car booked in for next Wednesday - the same day as we're off to Charters Towers (fingers crossed).

Burt65 · Senior Member

All disk brake pads have some form of wear limit indicator.

If you search online for "disk brake pads wear limit indicator" you will see all the pictures of the different way the manufacturer of either the car or the pads allow us to judge without removing them, when it is time to change them..

As mentioned by Corndoggy, make sure the disks have no deep lips on the edges, otherwise the new pads will wear out very quickly..

tempestv8 · Veteran Member

Hi Warren,

Are you referring to the front disc pads on the Isuzu D-Max? 2mm is a bit on the thin side and should be changed out sooner rather than later. One benefit of new pads is that the extra material helps to keep temperatures down. With so little friction material left, the brake calipers will get a lot of heat transfer from the rotors and you may experience brake fade if coming down a steep long mountain if there is not much engine braking available.

If it is the rear brakes and they happen to be drums, then 2mm might be OK, as drum shoes are fairly thin to start off with when new and they tend to last a long time. I am not familiar with the D-Max, but many of the utes tend to have drums in the rear.

Dick0 · Guru

tempestv8 wrote:
Hi Warren,

Are you referring to the front disc pads on the Isuzu D-Max? 2mm is a bit on the thin side and should be changed out sooner rather than later. One benefit of new pads is that the extra material helps to keep temperatures down. With so little friction material left, the brake calipers will get a lot of heat transfer from the rotors and you may experience brake fade if coming down a steep long mountain if there is not much engine braking available.

If it is the rear brakes and they happen to be drums, then 2mm might be OK, as drum shoes are fairly thin to start off with when new and they tend to last a long time. I am not familiar with the D-Max, but many of the utes tend to have drums in the rear.

And I have always wondered why.

erad · Guru

If you are replacing the brake pads yourself, have some new brake fluid handy and crack the bleed screw on the brake caliper just open as you press the pistons back. This disposes the brake fluid in the caliper, and you have to replace it with new fluid in the master cylinder. The reason for this is to remove the old fluid and replace it with new. Brake fluid absorbs water from the air and also if the calipers have been exposed to water. This drastically lowers the boiling point of the fluid, and if you brake hard, a lot of heat gets dumped into the fluid. If it boils, the brake pedal goes down to the floor - no brakes! Also, water in the fluid causes corrosion, and things then start to leak, losing fluid and needing new calipers as well. That is why manufacturers recommend replacing ALL the brake fluid every 2 years