After getting the cooling system under control, ,I decided to head out on some trails. The disco and the cooling system Disco dd great. Until it was time to head back down hill. Over the course of about a 15-20 minute decent the brakes over heated and faded to almost useless. Took a 20 min break on the side of the road and let them cool, babied them down for the next 20 min and all was fine. Now I can hear a clicking when engaging the breaks. It sounds like it is coming from the front drivers side. I removed the wheel and can see nothing noticeable.

For background; all four corners have been replaced with Power Stop slotted rotors and pads with less than 500 miles on them. A “new” junkyard ABS module, and full brake fluid flush also with less than 500 miles. I have no amigos and Traction Control was working throughout the day as it should.

One buddy thinks it could be the caliper. How do I go about investigating this?

 

Calipers are cheap and super easy to replace. Not a terrible idea to just replace all 4 and rebleed the system. The clicking could be a rock or other debris in the pads. It seems I'm always pulling things apart after a few wheeling trips to remove pebbles or other things stuck where they shouldn't be and make a ton of noise.

 

You "should" not get brake fade on disc brakes, it is possible but usually takes riding the brakes to the point you can smell it.

If that is the case check all 4 corners for function,if it is all good use your engine to brake. Low range 1st gear and idle down hillusing brakes as required to control engine revs and speed.

If not check for vacuum leaks it could be a brake booster issue.

 

That is how i came down the hill. In first and second but stayed in 4high. Definitely did get fade and could smell them. they weren’t glowing or anything but would not have been a good time riding someone’s tail at 50 mph.

I will check the vacuum. Who is the go to brand for calipers?

 

I wonder if drilled an slotted discs for off-roading are a good idea at all. Debris can get stuck there.

 

What brake fluid and pads are you using? That's what I would start with for brake fade issues. On my track cars, higher temp fluid and pads are necessary because street compounds don't hold up well to high heat. if you're smelling brakes and seeing fade, my first thought would be the pads aren't up to the task of holding the disco back on extended declines.

 

Im using Prestone DOT 4 fluid, and Power Stop Z36 pads and rotors. The Z36 is supposed to be Long life Truck and Tow.

 

Prestone has a wet boil point of 311F which is seems low to me. But I guess it's about in line with other non-racing oriented fluids. I would think the the Z36 pads would be pretty resilient to fade if they're towing.

 

Anyone expert take anything from these pics?





These are from Driver Front where it sounds like the clicking. I do see some chipping on the outside pad.

 

Those look kind of shiny to me, but overheat can do that. They seem to be a decent product.

If you did not follow the brake in procedure this could be normal, although unusual.

Check your caliper guide pins and make sure they are well lubricated and not binding, you can have some step on the brake and watch the caliper