Hey guys. I just finished my front brake replacement. What prompted me to do this was I was having violent shaking when I braked from about 35mph to 15 mph. I got two rotors and 4 pads from Brakemotive on ebay after seeing some good results here on MCF. After getting them installed I have noticed a considerable amount of drag on the front wheels. I first noticed when I was doing the right side. After I had the new rotor and pads in I put the lugs back on the hub (without the wheel) and had my dad hop in the drivers seat and turn the car on so I could see how the rotor spun in the caliper (just out of curiosity and to look it over). The first obvious thing I noticed was movement of the caliper itself while the rotor spun. It's not much movement, maybe a few mm, but movement nonetheless. This got me a little worried. Is my new rotor pre-warped?? It's hard to tell by looking at the rotor if it's slightly out of line or not.

To see if this was a real problem or not I put the wheel back on, lowered the jack, and took it for a spin. There was hardly a shake at all if not zero shake anymore! So my question regarding this is if there is wrong like a bent bracket or perhaps pre-warped rotor. There is obvious movement in the caliper as the rotor spins through it (because the pads are rubbing I assume). Is this going to cause premature wear of the pads or rotor? Eventually shaking? Or is it not a problem at all?

Back to my dragging pads. After noticing the movement of the caliper, it was apparent that the pads were dragging along the rotor even when the brakes weren't applied. I checked the drivers side which I had done earlier and it showed similar signs of dragging. There was an audible dragging noise coming from the wheel when I turned it by hand, AND it required a lot more effort than I would think needed to turn the wheel. I wasn't pulling out my back or anything, but it did require some effort, and the wheels came to an abrupt stop shortly after I didn't apply any more force. I did give both tires a good kick at 3 and 9 o'clock to try and free the pistons a bit but that didn't help at all.

So why the drag? Is this common in new pads? This seems like it will cause a lot of unnecessary heat and friction. Perhaps this drag will go away while the brakes are used and 'broke in'. Anyway, looking for your advice on my situation.

Here's a pic because everyone likes looking at new brakes!



Thanks!

 

Over time the caliper pistons can become pitted, and/or the bubber boot can accumulate dirt around the piston. Either of these situations can cause the piston to not fully release when you take your foot off the pedal. Dirt trapped between the rubber boot and piston is a fairly common problem. I can't say for sure that this is your problem, but it could be. If the pistons and bores are in good shape you can get a rebuild kit for the calipers and renew them. It is also common for new pads to have a slight drag on the rotor until you get a couple hundred miles on them. I would drive the car for a while and see if the situation improves before worrying too much about the drag unless it's severe and causing the car to drift to one side or the other. If the calipers have excessive movement in the bracket you may need new mounting hardware. The excessive clearance could also be causing the 'shaking' when you apply the brakes.

 

Thanks for the reply. I'll leave them be for a while and see if it improves. I haven't noticed a significant drag to one side or the other.

By mounting hardware do you mean the caliper bracket and the two sliding bolts that hold the caliper on?

If I didn't point out in my OP, the shaking is gone now with my new rotors.

 

It could be wear to the brackets, or the bolt/bushing. You'll need to have a look and see if you can determine where the excessive clearance is. The caliper should be able to move a little, but it's fitment shouldn't be sloppy either.

 

Maybe I'll pick up a spare caliper and hardware next time I'm at the pull yard. I'll keep an eye on it for now.