Solved - Weird front brake pad issue on '01 Sport Trac

[koda2000]

Hey Guys.
I haven't been here for months, but I have a problem with strange front brake pad contact/wear on my '01 Sport Trac RWD.

First some background...
I decided that it was time to replace the front rotors on my Sport Trac. The old ones were very worn and had gotten very rusty while the truck sat idle for almost 2 years. I went to RockAuto and looked up my vehicle and to my surprise I learned that the Sport Trac rotor is not the same diameter as the regular 4 door Explores it is slightly larger, which I guess I can understand as you might put/pull more weight on the pickup version, though oddly both the regular Explorer and the ST use the same calipers and brake pads. I had changed the brake pads on the ST when I first got it 6 years ago and I used the same brake pads as the ones on my '01 Eddie Bauer without any problem or uneven wear for 6 years.

I ordered new Raybestos brake rotors, Timken bearings and new rotor seals from RA and I took my old ceramic brake pads back to AutoZone for a free warranty replacement.

Last Saturday I decided to go ahead and do my brake job. Everything went smoothly (I've done hundreds of disk brake pad jobs and at least 20 rotor/bearing replacements and/or resurfacings over the years and have never had a problem.

After finishing up I took the ST for a test drive and a brake pad bed-in and everything seemed normal. When I got home I noticed that the wear pattern on my new rotors was not equal. It looked like only 1/2 the pad was contacting the rotor's outside surface. Normally I'd question the caliper or caliper bracket was bent, but before this brake job my pad wear was normal. I checked the other side and saw the same wear pattern.

Today I took apart one side completely to make sure I didn't do something stupid. I found no indication that the caliper, or caliper bracket were misaligned, nor that the rotor was somehow not centered. Looking at the new brake pads they were worn differently. The inside pad showed contact wear on its lower half only and the outside pad had wear on its upper half indicating something was ****ed. I've never encountered this before. Does anyone have a clue what the problem is? The truck drives and seems to stop okay, though I'm currently only getting 1/2 the pad-to-rotor contact. As the only new parts are the rotors and brake pads I'm thinking the problem must be there.

Rotors Ordered - Raybestos 680021R
Brake Pads - AutoZone DG652C

 

[swshawaii]

A big welcome back Phil! I had a similar problem with front disc brake pad contact and ended up replacing the calipers that solved the issue. How calipers fixed it I have no idea. LOL. Also had the same issue with both REAR disc rotors on my 2005, but 2001-02 have drums. Remanufactured calipers fixed that too. Weird because all the slide pins and phenolic pistons were moving smoothly. And yes, I made sure they were the correct pads.
Hope to hear from you more often, you have been missed by many.

 

[swshawaii]

I vaguely remember there was a difference with front pads. Something about the end letter on the pad part number DG652C.

Know it's a PITA, but go to AutoZone and physically compare both pads with their DG652 without the C.
https://www.autozone.com/brakes-and...ads/duralast-gold-brake-pads-dg652/529520_0_0

 

[koda2000]

I vaguely remember there was a difference with front pads. Something about the end letter on the pad part number DG652C.

Know it's a PITA, but go to AutoZone and physically compare both pads with their DG652 without the C.
https://www.autozone.com/brakes-and...ads/duralast-gold-brake-pads-dg652/529520_0_0

The "C" stands for ceramic. Apparently I got the last set that they had and they do not plan to get anymore in, so I can't compare and the old pair has already been turned in. Maybe I should just try a set of their cheap organic pads to see if there's a difference?

 

[swshawaii]

OK, I guess AutoZone has a different part numbering system. Wagner uses a B suffix on one and both are semi-metallic. (SX833 vs. SX833B)

 

[429CJ-3X2]

Good to hear from you, Phil! Wish I had something more to offer, but that's about it.

 

[Josh P]

I'd suspect the caliper slide pins.

 

[koda2000]

I'd suspect the caliper slide pins.

I removed, cleaned, lubed the slide pins during the brake job. They looked fine and they weren't causing a problem with the old parts. I just don't get it. Maybe I'll just try replacing them too. They're cheap enough.

 

[koda2000]

OK, I guess AutoZone has a different part numbering system. Wagner uses a B suffix on one and both are semi-metallic. (SX833 vs. SX833B)

I saw different part numbers for front pads while looking at RA's on-line catalog, but I assumed these were just diff manufacture's part numbers. The pads looked the same in their info pics. The AZ pads looked just like the ones I'd removed, though I didn't measure them and they seemed to fit perfectly. I'm going to replace the slide pins to see if that makes a diff.

 

[koda2000]

Solved - It turns out that the ST front pads are not the same as the regular Explorer's. I could have sworn I'd used the AZ's 652's when I changed the brake pads on the ST 6 years ago, but the correct Sport Trac front pads are AZ's 833's. The only difference is that the 652's have 2 little bumps on the top of each pad and the 833's do not. Apparently the bumps interfered with the ST's calipers and ****ed them to one side. Oh well, I can save the 652's for our Mountaineer or Eddie Bauer Expl and I now have a spare set of caliper slide pins.

 

[CDW6212R]

Welcome back here Phil, and I'm glad you figured it out.

I suspected that was it, when I read you posted the pads and calipers were the same etc.I learned that in 2006 when I swapped Sport Trac calipers onto my 99. The pads are similar in size, I tried both pads in both caliper versions. Since they wouldn't work any better, I kept my original calipers on my 99, so I've been using the same pads for my Explorers. I stored the Sport Trac calipers as spares, her'e what they looked like, a bit more gold in color.

 

[koda2000]

Welcome back here Phil, and I'm glad you figured it out.

I suspected that was it, when I read you posted the pads and calipers were the same etc.I learned that in 2006 when I swapped Sport Trac calipers onto my 99. The pads are similar in size, I tried both pads in both caliper versions. Since they wouldn't work any better, I kept my original calipers on my 99, so I've been using the same pads for my Explorers. I stored the Sport Trac calipers as spares, her'e what they looked like, a bit more gold in color.

View attachment 330509

Yeah, other than the 2 bumps on the top of the non-ST pads, the Explorer pads are identical. In retrospect I guess I could have just ground the bumps down, but I just bought a set of the 833 pads for the ST and will use the 653's on one of my other vehicles. I took the ST around the block and bedded the new pads and it stops on dime now.

BTW - I had the trans in the ST replaced back in Feb. The old one was trashed big-time. It now runs and drives like a new truck.

 

[JustAnotherMember7]

It is nice to see you back Koda! We've missed you, so welcome back!