I have a strange brake issue with my 2007 Ford Escape XLT (3.0 litre, front wheel drive). This issue occurred around the time when I changed from my summer tires (on factory rim) to the winter tires (on black rim).

The rear drum brakes are braking at different times from each other / and after the front brakes.
I can hear and feel that the left and right rear drum brakes are activating a fraction of a second *after* the two front disc brakes. They are also not activating at the same time.
This is causing the vehicle to have erratic braking and occurs at even low speeds (40km/hour).
This appears to occur only when moderately to firmly applying the brakes. (not when brakes are lightly applied)

This is causing the front end only to brake at first, then the rear end pushes the whole vehicle forward and slightly to the side (fishtail style) in the rear. The vehicle acted similarly years ago, due to a faulty ABS sensor on rear wheel. The vehicle has been scanned and shows *no* abs or other fault indicators.

The front brakes are new, rotors and pads changed recently.
The rear brakes are original (100KM) on them, the shoes look to have little wear and no rust visible (which seems strange for their age/km).
The drums have been sanded and appear smooth as well.
The rear flex lines have been swapped out new, with no results.
The rear brakes were serviced *twice* by Ford, with no results.
The parking hand brake was overly tight, (with 2-3 clicks worth of play).

Any suggestions?

 

So if you change back to original stock tires it goes away? It still sounds like a abs concern. Most of the time it does not set a light when the tone rings crack have you checked the tone rings for looseness or cracks?

 

I haven't tried the summer tires on it. It occurred right after having the winters put on.

I figure the dealership must have banged an ABS sensor (damage or knocked out of place) or the tone ring as you suggested was affected (dirty/cracked/loose). Going to take a look at these two things today, and will post the findings.

So far it's been to the dealer twice and several independent shops with no resolution. One mechanic also mentioned it could be the ABS pump or full ABS module, but not sure that would explain just 1 wheel acting up.

 

Just to help eliminate some possibilities. You might remove the ABS fuse and see if the problem is still there. If so, not necessarily ABS related. I gone, now you know where to look throughout the ABS system.

 

I will check the drive with the ABS fuse out tomorrow, sounds like a good idea.

I've replaced both rear ABS sensors, inspected the rear tone rings, they are clean and attached properly, no signs of damage. The issue is still there.

I can hear the rear left (driver side) brake about a quarter second before the rear right (passenger) brake kicks in. This causes a slight fish tail.

 

Have you checked the front rings closely though? Tires and rims not of different size right front to back?

 

have you put the summer tires back on?
tried driving with them and gotten the same braking condition or did the problem go away?
i'm thinking the tires are different sizes and the computer is receiving different speed signals for the front and rear... and is returning weird pressures to the brakes.
winter and summer tires with the same size designations may still have different circumferences.

 

I checked the tone rings in back, they are clean/tight/in good condition.

I changed out the rear ABS sensors with new.
The vehicle is still making a "clunk" noise (sounds like something heavy in trunk area pushing forward during stop), then you can hear the rear left drum shoe activating a split second before the rear right does.

The winters are same size as the summers.
I had them on last year and didn't experience this issue, but I'll try swapping them over for a test drive just in case.
I'm also going to try pulling the ABS fuse and see if it still acts the same.

 

that clunk sound isn't good. you need to find the source.. it could be causing a wire from a sensor to rub and short out or break. if something is moving, it can cause your vehicle to dart to the side when you brake and accelerate. or worse come apart....
the rear brakes applying one before the other is un-equal pressures on the brake pads... a cause could be a restriction in one brake line or a sticking hydraulic cylinder.
with the clunk sound, something is moving. check for a pinched brake line...

 

yes but have you checked the front rings closely?