that would make sense, but for them to install the wrong parts, there would have to be a caliper that had the correct external dimensions, but has a larger bore diameter than the original/stock caliper. that's the only physical change that would produce the problem that I have. that' or by working on the front, they somehow introduced air into the rear system such that it's effectiveness has dropped.

I don't think either of those are possible, so I'm starting to wonder if it's an electrical problem that was caused by the original issue, but was not noticed and resolved by the dealer. I've never seen brakes be so puzzling.

 

 

Is it possible to install the wrong bracket on the knuckle thus allowing the wrong caliper? Are the knuckles different?

 

I do know that some aftermarket calipers do come with the bracket. Is the bracket new?

 

The more I think about this the stranger it seems. If you do confirm you have the right parts installed then disconnect the batteries for a while. Make sure everything is dead. Even turn headlights on while disconnected to drain everything. Then hook back up and see if it changes. You guys may be on the right track with the advancetrak. I'm not familiar with it. Hopefully it does have some kind of code. If you're lucky a battery disconnect will clear it. Battery disconnects don't ALWAYS clear codes tho

 

No. That's the point. Both the bracket to knuckle and the caliper to bracket locations are changed.

The only deviation was during the '05 to '11 years on the rear brake. Akebono on the previous design used the same rear caliper design across everything in the P131 platform, Excursion, SRW and DRW pickups. TRW initially thought it was a better idea to go with different calipers SRW and DRW. Later in '08 they conceded there was no reason for it and converted to a single design rear brake for all applications. Their stubbornness just made a mess of the early years. The front caliper '05-'011 never changed.

But Ford has in its design criteria to not do carry-overs when major changes occur so in the public domain people don't alter the brake balance and leave Ford in a position after an accident to be left with "you could have prevented this..." liability. Well, to a point....... The person has to go radical.

 

Jack - thanks for confirming that there is no other caliper that could be installed on the front. yup, bracket and caliper came together as an assembly. (as shown below). so that would almost rule out a physical problem. no bigger pistons on new calipers causing the problem and I really don't see how they could have gotten air into the rear system to reduce it's effectiveness.

I could disconnect the battery and test, but that will leave some uncertainty as to whether there was an error there. I might take it to my local dealer and ask them to check if there is indeed a code. then I would know a possible source of the problem.

the other thing I'm wondering, if the wheel hit 350 degrees and melted the hub cap off, could it have damaged a sensor. I think there's only a wheel speed sensor, so if either the wire to it or the sensor itself was damaged, what would Advancetrac do? on my initial stop I had a hub cap and no error message. then I pulled off the highway and the hub cap was gone and I had the "service Advancetrac" message. then I drove 5 miles to the dealer and the message was gone. at some point Advancetrac was upset and it was not because the tires were sliding because they were not, so what caused the message? I'm starting to think the sensor or wire was damaged and the dealer did not catch it.

 

Since TRW likes to cast in the piston diameter into the caliper housing, based on your first image I think we can re-confirm you have stock front calipers.













FM 2160 FE was the original equipment friction material on the '05 to '11 model years.

So friction material coefficient can make a difference. FE friction vs FF friction codes. Each letter represents something between a point of friction, E = 0.25 to 0.35, F = 0.35 to 0.45.

While using a friction material that has a higher coefficient of friction, it may feel better to the person who is driving the vehicle because the pedal effort during normal driving is lessened, and in most cases, especially with a vacuum boosted vehicle, the pedal travel is shorter. Great, you have better brakes.

However, both the driver and the ABS functions have limitations in reaction time and pressures. And in full panic mode stopping, the release time of the ABS can be longer and lower pressure trying to compensate. So during that 3 to 4 seconds of stopping from 60mph overall the applied hydraulic pressure is lower, the stopping time is increase by a tenth of a second or two, and most importantly the stopping distance is longer. At 60mph, 88ft per second. So feels better isn't necessarily stopping better when it really counts. And why in Europe EEC13 regulates that aftermarket replacement materials have to be within 10% COF of the original materials (OE). There are no such rules in the USA or Canada. The ABS engineer and recal the algorithms, but you can't recal your muscles. Public service announcement over.



I really think you have something going on with the electronics, and I agree when you originally said the hubcap melted I thought there was other damage. Cluster lights tell of an in-process fault (on-off) or a hard fault (always on).

 

gave up and took it to my local ford dealer - I purposely did not pull the battery ahead of time because I wanted to know if there was a code in the system for Advancetrac, that might be causing the rear brakes to be weakened. Ford said "no code" - UGH

Then they test drove it, reproduced the front skid marks. Took it back out with the computer hooked up to display the wheel speed readings and said all 4 wheels read same speed, (except one time they noticed the front left reading 3 MPH below the others, but dismissed it because it only happened for a moment and they could not see how that could cause my problem).

I talked to the tech for a while trying to figure next steps. he's frustrated as he can't think of a cause. His shot in the dark was for me to replace the front rotors. He said, the original dealer used aftermarket parts to get me back on the road. he said with a 2WD the tone ring for the wheel speed sensor is on the rotor. his long shot is that the aftermarket rotor is slightly out of spec causing speed reading problems, thus causing it to allow the fronts to skid and somehow reducing brake force in the rear. then they priced out replacing with Ford rotors at $850 and we all agreed that would be an expensive shot in the dark.

So back to square one:

Symptom/problem - at medium brake level, the front tires leave long black skid marks (in other words, the tires are rotating maybe 10 MPH slower than the car is traveling). the fronts appear to be overpowered compared to the rears. In wet weather, the ABS kicks in much earlier than before and my braking distance it a good bit longer.
When did it start - one road trip, left front caliper stuck and the wheel hit 350 degrees and melted the hub cap off. out of state Dealer put aftermarket rotors, calipers, pads and hoses on the front. noticed problem on way home.
Troubleshooting since: - replaced the front pads a second time, replaced all 4 tires, bled the brakes and ford verified there are no codes in the system - but the problem remains.

not sure what I'll do next. I could replace the rotors (myself) or the wheel speed sensor. drive the truck off a cliff.

 

 

you are 100% right - no reason to replace more parts till I test the hydraulics without interference from Advancetrac and ABS. I will do an online search to find which fuses I need to pull.

I was surprised I could not find anyone at the dealer who could tell me the conditions under which the Advancetrac changes the front to rear brake bias. I suppose it would have to sense the front wheels were spinning faster than the rear (meaning rear lock pending so it reduces rear pressure to avoid lock).

I also agree with the physical checks needed - after the fuse pull to verify the hydraulics are working correctly

 

The owners manual will show all relevant fuses for your model year. 3mph under speed would tell thats the wheel thats skidding, not the rear. It seems weird whats going on here.

 

pulled fuses 54 (ABS), 86 (ABS coil feed ) and 96 (ABS pump) and went for a test. before pulling fuses, it would pre-maturely lock the fronts and the rear braking was reduced. once fuses were pulled, it locks the rears first. I measured rotor temps and front were 370's while rears were 220's.

My take away is the electronics are reducing the pressure to the rear too much. I don't really know what's causing that, but given what has been replaced so far, I think the next step is to try a new set of rotors (theory being there's something wrong with the tone ring on one of the ones the dealer put on). if that does not work I think my next step is the wheel speed sensor on the side that got hot (due to frozen caliper).

 

So I replaced the front rotors and the problem went away. in the process, I noticed the wheel speed sensor on the left front was caked with metal shards from when the caliper was frozen. so either there was a problem with one of the previous rotor tone rings or the wheel speed sensor did not like all the metal stuck to it.

 

Either could be the fault. You'd have to swap rotors back to A-B the experiment. But no matter, glad you have it figured out.

Any chance the dealer installed rotor has witness marks from touching the sensor?