2017-2020 Lincoln MKZ Front vs Rear Brakes: What Wears First and What to Replace

By Core Brake Parts Tech Team — Circleville, OH warehouse

On a 2017-2020 Lincoln MKZ the front brakes almost always wear out first. The front pads and rotors do most of the stopping work, so on most cars the rears last roughly twice as long. The exception is a rear caliper that drags or an electric parking brake that is not releasing fully, which can wear the rears out early - so always measure both axles before you buy parts.

How the MKZ Brake System Splits the Work

The MKZ uses disc brakes at all four corners. The front axle carries the engine and transmission, and when you brake, the car's weight shifts forward onto the front tires. Brake makers design for that: Bendix explains that road cars ship from the factory with a front brake bias because most of the weight sits over the front wheels, and forward weight transfer during a stop is the main reason front rotors are larger in diameter than the rears. The MKZ is no different. The fronts turn more of the car's motion into heat on every stop, so they shed pad material and rotor thickness faster.

The rear brakes on the MKZ also do a second job. The 2017 MKZ owner's manual states that the car has an electric parking brake that replaces the conventional handbrake, with a switch on the instrument panel to the left of the steering wheel. The parking brake is applied by motors at the rear calipers. That matters when you service the rear pads, which we cover below.

The MKZ also has Auto Hold. According to the owner's manual, Auto Hold uses the vehicle's brakes to hold the car once it has come to a stop, for example at a traffic light, and in some cases it hands over to the parking brake. Holding pressure at a standstill does not grind pad material the way a stop from speed does, so it is not a major wear factor, but it is one more reason the rear calipers need to move freely.

Front vs Rear at a Glance

Symptoms: Which End Is Worn?

The owner's manual is plain about the warning signs: occasional brake noise is normal, but a metal-to-metal sound, continuous grinding or a continuous squeal can mean the brake linings are worn out. A continuous vibration or shudder in the steering wheel while braking should also be checked. Here is how to narrow down which axle is the problem:

• Steering wheel shake when braking points to the front rotors. Pulsation you feel mostly in the seat or pedal with a calm steering wheel can point to the rears.
• Squeal or grind from the front is the most common complaint, because the fronts wear first.
• Rear grinding on a car with healthy fronts is a red flag. It usually means a rear caliper or its slides are dragging, or the parking brake is not fully releasing.
• A hot wheel or strong burning smell after a drive points to a dragging caliper on that corner.
• Park brake messages in the cluster. The manual lists messages such as Park Brake Not Released, Park Brake Limited Function Service Required and Park Brake Malfunction Service Now. Any of these means the rear system needs a look before you blame the pads.
• Longer pedal travel or a red brake warning lamp is not a wear problem. The manual says that if the brake system lamp comes on while driving with the parking brake off, it indicates low brake fluid or a brake system malfunction, and the car should be checked immediately.

What Wears Rear Brakes Out Early

If your rear pads are thinner than your fronts, something is wrong. EBC lists the usual causes of rapid pad wear, and several apply directly to the MKZ rear axle:

• Dragging calipers. EBC recommends servicing and resealing calipers every 3 to 5 years, especially single-piston sliding types. Seized slide pins keep the pads in contact with the rotor.
• Mismatched pads front and rear. EBC advises using a similar grade of pad front and rear. Putting a more aggressive compound on the rear upsets the balance and speeds up wear.
• Scored rotors. Badly scored rotors rapidly escalate pad wear, so new pads on a grooved rotor will not last.
• Driving with the parking brake on. The owner's manual warns that driving extended distances with the parking brake engaged can cause brake failure. The MKZ will show a warning if the electric parking brake is set and the car goes over 3 mph, but a partially released caliper can still drag.

The Fix: What to Replace and When

Front brakes. Most MKZ owners will do front pads and rotors first. Measure the rotors when the pads come off. Power Stop notes that the minimum thickness is engraved on the rotor - on the side, in the vanes or on the hat - and that if the rotor is below that number or would need to be cut below it, you need new rotors. They also recommend replacing rotors in pairs, because a thickness difference side to side can make the car pull. Shop replacement brake pads and brake rotors, or ceramic brake pads if you want low dust on the MKZ's large wheels.

Rear brakes. Check the rears every time you do the fronts. If they are at or near the wear limit, do them in the same visit. If they still have plenty of material, leave them and check again at the next service.

Both axles at once. If both ends are worn, a matched kit saves time and keeps the pad compounds the same front and rear, which is what EBC recommends. We carry a 2017-2020 Lincoln MKZ front and rear brake kit with rotors and pads for all four corners.

How often to look. The MKZ maintenance schedule calls for inspecting the brake pads, rotors, hoses and parking brake at every oil change interval, and the manual says not to exceed one year or 10,000 miles between service intervals. That is the easiest time to catch uneven wear before it becomes a rotor job.

What to Replace at the Same Time

• Hardware and slide pins. New clips and cleaned, lubricated slides stop the drag that eats pads early. See our brake hardware kits.
• Calipers if a piston is sticking, a boot is torn or one corner runs hot. Shop brake calipers.
• Front brake hoses. NHTSA recall 23V-162 (Ford 23S12) covers 2013-2018 MKZ models with non-hybrid engines built with suspect front brake jounce hoses between February 3, 2012 and July 19, 2017. Ford's report says the hose's internal braid can fatigue from suspension and steering movement and rupture, causing a progressive fluid leak, longer pedal travel and weaker stops. Have the recall checked by VIN at a dealer before any front brake job. Outside the recall, cracked or bulging hoses belong in the brake hoses collection.
• Brake fluid. The owner's manual specifies Motorcraft DOT 4 Low Viscosity (LV) High Performance Motor Vehicle Brake Fluid, or an equivalent meeting Ford specification WSS-M6C65-A2, and warns that other fluids may degrade brake performance. Keep the fluid clean and dry.

How Hard Is the Job?

The front pad and rotor job on an MKZ is a standard floating-caliper job that a careful home mechanic can do with basic hand tools, a torque wrench and a way to compress the caliper piston. Torque the caliper bracket bolts, caliper bolts and lug nuts to the values in the factory service manual.

The rear job is harder because of the electric parking brake. The owner's manual describes a Park Brake Maintenance Mode, a special mode used to allow service of the rear brakes. The rear caliper pistons have to be retracted electronically through that mode, typically with a scan tool that supports it, before new pads will fit. Forcing the piston back by hand can damage the parking brake actuator. If you do not have a capable scan tool, have a shop handle the rears. After any brake job, pump the pedal until it is firm before you drive, then bed the new pads with a series of moderate stops.

Frequently Asked Questions

Do the front brakes on a Lincoln MKZ wear faster than the rear?

Yes, normally. The MKZ has front brake bias and weight shifts forward when you stop, so the front pads and rotors do most of the work. On most cars the rears last about twice as long as the fronts.

My MKZ rear pads are worn more than the fronts. Why?

That points to a problem rather than normal wear: a sticking rear caliper or slide pin, a parking brake that is not fully releasing, or a mismatched pad compound. Inspect the rear calipers before you install new pads, or the new pads will wear out just as fast.

Can I push the rear caliper piston back on an MKZ?

Not the usual way. The rear calipers carry the electric parking brake, and the owner's manual describes a Park Brake Maintenance Mode used for rear brake service. Put the system in that mode, usually with a scan tool, before retracting the pistons.

Should I replace rotors every time I replace pads?

Only if they are below the minimum thickness stamped on the rotor, would go below it if resurfaced, or are warped or badly scored. When you do replace rotors, do both sides of the axle together.

What brake fluid does the 2017-2020 MKZ use?

The 2017 owner's manual specifies Motorcraft DOT 4 Low Viscosity (LV) High Performance brake fluid, or an equivalent that meets Ford specification WSS-M6C65-A2. Check your own model year's manual to confirm.

Is my MKZ part of the brake hose recall?

Recall 23V-162 covers certain 2013-2018 MKZ models with non-hybrid engines built between February 3, 2012 and July 19, 2017. The vehicles were not built in VIN order, so check your VIN with a Lincoln dealer or on the NHTSA recall site.

Sources

1. 2017 Lincoln MKZ Owner's Manual (Ford) - electric parking brake, Park Brake Maintenance Mode, Auto Hold, brake noise guidance, inspection schedule, DOT 4 LV fluid spec
2. NHTSA Part 573 Safety Recall Report 23V-162 - front brake jounce hose recall scope, cause and risk
3. Bendix: Brake Bias Explained - factory front bias, forward weight transfer, larger front rotors
4. EBC Brakes: Rapid Pad Wear Faults and Cures - rear pads last about twice as long, matching compounds, caliper service, scored rotors
5. Power Stop: Minimum Rotor Thickness - where minimum thickness is marked, replacing rotors in pairs