2001 kia sportage brake problems

kia
sportage

#1

My sportage is on it’s 5th set of rotors. The 1st set set had to be replaced 30000. The 5th set was put on at 160000. It’s ridiculous the way it eats them up. At around 145000 I replaced the wheel bearings calipers rotors and pads (did the wheel bearings and calipers as preventative maintenance). Both rotors had groves on the inside and were warped after only 15000 miles.

I don’t see how 2 new calipers could both be sticking in the same way. This is just one of several problems, but it seemed like a good place to start.


#2

First, rotors aren’t what they used to be. These days they are thinner to start with, and, especially for the cheaper rotors, are not made of the highest quality steel. If you keep putting “economy” brand rotors on I would just bump it up to a known brand at the middle quality level or higher. Do the same with the pads - they can have as much to do with it as anything else.

That said you haven’t given enough info about what is happening to the rotors. There is a vague reference to warping and a reference to grooves. As for the grooves, all rotors will get grooves in them when used - they end up looking something like an LP vinyl record. Unless you’re talking about very deep grooves in which case that really only comes from problems with the pad - such as running the pads down to nothing.

As for the rotors “warping” (maybe they are and maybe they’re not), there are all sorts of things to make sure of. One is that when the rotor is installed its mating surface w/ the hub is perfectly clean/smooth. The lug nuts must be installed onto the wheels with a torque wrench and put to the correct specs. This applies anytime a wheel comes off. You mention calipers but have you actually checked for sticking? Check the temp at each wheel after you’ve driven for a while. If you find excess heat there are multiple reasons that the brakes can stick. The caliper slides get sticky - those should be cleaned and lubed anytime to tear down the brakes. The flexible brake lines can deteriorate and not allow pressure to be relieved.

If you are buying bottom rack brake parts I would just stop. I had a long term go 'round with my brakes once that may be similar to yours. I always just went to a chain-type parts store and bought the cheap stuff. There was a time when that was adequate. I don’t think that’s the case anymore. Finally I just bought middle grade pads and rotors from NAPA and I no longer have any problems.


#3

As to the quality of the parts, the last 2 sets of rotors were the best rated Bendix parts Discount Auto Parts carries. The pads were the cheap Wearever silver line. I use synthetic dot4 brake fluid. I did a complete replacement of the brake fluid at 145000. I did not change the lines though.

A set the cheap pads last through 2 rotors.

The grooves on the rotors were only on the inside and 1mm or less, the warping I mention is from the feel of the pedal pulsing and soft-hard back and forth bouncing stop. I’ve done a probably 50-75 sets of brakes and i worked a in a shop 20 years ago, and I’ve never seen a properly maintained vehicle with so few miles (per rotor)have problems like this. I have seen some really screwed up rotors where the pads have been worn down the rivets with 1/4" groves in the rotors, but never at 15000 miles.

Sounds like I need to replace those flex lines replace the fluid and clean the calipers. And in addition to that build a forge and start producing my own steel so I can get the quality of yester-year.
Does that sound about right to you, and what would you suggest on the pads ? I don’t mind mind paying for quality just never saw any difference between the cheap pads and the most expensive ceramics.

Thanks in advance.


#4

Upgrade the pads with the rotors. I have no specific suggestions as to brand or anything else - just a mainstream brake parts brand at their middle level of quality or above (Bendix is fine). The cheap ones are likely to have less consistency in the friction material (perhaps then producing the rotor grooves) and more likely to leave residue behind on the rotors. While rotors do warp, often the brake pedal shudder isn’t from an actual warping. Rather it comes from an uneven rotor surface. Pad residue is one reason for this - a little smear of pad material, a little build up over time, gives you hot spots on the rotors - all downhill from there.