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I've just replaced the pads on my daughter's '01 F-150 2WD pickup and was wondering how much should the pads be dragging against the disk itself when there's no pressure on the brake pedal?  The inner pad was worn down to the metal while the outer pad still had about 25% wear, or a little less, to go.  According to the diagrams on the new pads' box it says this is symptomatic of either the slide guides not working correctly or the pistons are stuck.  The pistons retracted all the way back in when I installed the new pad on that side and I polished the slides up with steel wool and emery cloth.  There doesn't seem to be any drag on the steering wheel to that side when I test drove the truck and the brake itself had no noise during braking either.  Should I be concerned about the drag on the disk?  Will that result in premature wear on the pads and disk rotor?

Thanks.  

that kind of thing has been seen before where the inner rotor face was warn before on the previous pad install.. the rough surface will wear that pad faster...

i am taking that the caliper slides are free to slide ....

so when the caliper is off in your hand.. the bushing with the rubber boots is free to move fully



the boots come in a caliper hardware kit usually sometimes alone..




if the caliper pins are not free to slide...  when the pistons extend the brake caliper cannot slide back slightly  to allow the inner pad and the outer pad to place equal pressure on both sides of the rotor for proper brake wear....

when the caliper slides bind... sometimes they will allow almost equal pressure. but will stop the caliper from freely returning to center ...      i have found a few that somebody used the wrong grease... DO NOT ever use dielectric tune up grease as any kind of lube... one caliper slide was so tight it would not budge when i tried to break it free on the 30 ton press..



so if your caliper sides are free to move.. the brake wear you experienced was just from the rough inner surface..  

by the way... look at the brake pads below.. the top pad has a little metal tab at about the 5 o clock position... thats the low pad warning sensor..



that little tab will rub the rotor and make the brakes squeal until you touch the brake pedal... then it will get quiet.. that notifies the driver that the brake pads are wearing down.. before it tears into the rotor...


if you look at the second pad down.. you will see the wear sensor in the same location.. as that pad goes on the other side of the truck...  

Thanks for the info!  I only looked at the pressed metal clip-ons when I was working on them yesterday.  I'll go back and look at them again tomorrow.  I had to buy a breaker bar today to see if I can get the bolts off of the passenger side caliper as my 1/2" drive ratchet wasn't long enough to provide enough leverage.  May even need to find a pipe to lengthen that one too.  Those two bolts are in there solid!

I did see the squeaker tab on the old pads.  They'd been bent back to where they were even with the pad.  No telling how long my daughter has been driving on them like this.

I did not have the rotor turned that had the bad pad on it.  I'm hoping the pad and rotor will wear into themselves and smooth out the little roughness that was on the rotor.  As I said before there was no noise when I braked with the new pads on, nor was there any vibration.  

Speaking of grease in the caliper bushings -  I did go back and check that driver's side caliper and it was pretty sticky so I pulled the caliper off by unscrewing the bushing pin screws and extracted the pins.  They had what was left of a blue grease of some kind on them.  I have some Pennzoil 707L wheel bearing grease.  Would this be a suitable grease for these pins and bushings?  The rubber boots looked fine, still pliable, no cracks.  

i am not familiar with grease specifications by number...


it will probably work..

i like white lithium grease.. or Silglide...    

since the rotor faces are worn on that side... you will probably be back in there sooner than later...





or




or



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i like the little pouch or the white lithium over the sticky synthetic stuff..   as i use white lithium on the lug nuts also... and you cannot use the synthetic lube on them as far as i know..
the CRC white lithium grease also comes in a large plastic toothpaste type of tube ... about 10 inches long..  

Thanks for both of your replies.  I'll probably be back when I tear into my dad-in-law's engine with the coil problem.  Got to get the scanner from Autozone first, however.