Bought a used knuckle should there be any play at the bearing has a little not a lot

I wasn't sure if you were asking about the front, rear wheel or other assembly.
The most common problem is the front wheel bearing:
I have a 2002 Escape and have changed my bearings. All the Ford Escapes are the same thru 2010. The front wheel bearings on the Escape are simple cartridge bearings, or Gen1 bearings, that are pressed onto the hub and knuckle. They are not so simple to replace. Unless you have the experience and tools, you'll need to take it to the dealer or a shop.

You will need a press and the correct press tools.
The knuckle/hub assembly needs to be removed from the vehicle.

Here's the short version:
Remove the tire/wheel.
Remove the brake caliper w/ bracket.
Remove rotor.
Remove the ABS sensor.
Remove axle nut and press the axle inwards, until loose. (sometimes easy, usual needs special tool).
Remove the strut bolts, tie rod, and the lower ball joint from the knuckle/hub assembly. Each of these connections can have it's issues.
Press the hub out of the assembly. One half of the inner race will be stuck on the hub. Use a bearing splitter to remove that half.
Remove the snap ring from the knuckle.
Press the rest of the bearing from the knuckle.
Press the new bearing into the knuckle. Press on the outer race only!
Snap ring.
Make sure the dust sheild is still in place.
Press the hub into the bearing. The bearing must be supported on the inner race only!
The point is that you must not press thru the balls in the bearing. That can cause the bearing to get brinnelled.... not good.
Reassemble the knuckle on the vehicle in reverse order. I like to put a little grease on the axle spline. The axle spline has a little helix on it... about half a degree. It's supposed to be a tight fit. The torque on the axle nut is 300Nm (about 220ft-lbs?). This torque is very, very important. It is needed to keep the bearing together and at the correct preload, so use a big torque wrench.

...or you can take it to the dealer.

Good luck. Here are some pictures that may help illustrate the difficulty:
Knuckle assy with lower control arm.

http://s2.photobucket.com/albums/y48/ZeeVert/2002%20Ford%20Escape/?action=view&current=CIMG1256ss.jpg

I have a 2002 Escape and have changed my bearings. The 2006 is the same. The front wheel bearings on the Escape are simple cartridge bearings, or Gen1 bearings, that are pressed onto the hub and knuckle. They are not so simple to replace. Unless you have the experience and tools, you'll need to take it to the dealer or a shop.

You will need a press and the correct press tools.
The knuckle/hub assembly needs to be removed from the vehicle.

Here's the short version:
Remove the tire/wheel.
Remove the brake caliper w/ bracket.
Remove rotor.
Remove the ABS sensor.
Remove axle nut and press the axle inwards, until loose. (sometimes easy, usual needs special tool).
Remove the strut bolts, tie rod, and the lower ball joint from the knuckle/hub assembly. Each of these connections can have it's issues.
Press the hub out of the assembly. One half of the inner race will be stuck on the hub. Use a bearing splitter to remove that half.
Remove the snap ring from the knuckle.
Press the rest of the bearing from the knuckle.
Press the new bearing into the knuckle. Press on the outer race only!
Snap ring.
Make sure the dust sheild is still in place.
Press the hub into the bearing. The bearing must be supported on the inner race only!
The point is that you must not press thru the balls in the bearing. That can cause the bearing to get brinnelled.... not good.
Reassemble the knuckle on the vehicle in reverse order. I like to put a little grease on the axle spline. The axle spline has a little helix on it... about half a degree. It's supposed to be a tight fit. The torque on the axle nut is 300Nm (about 220ft-lbs?). This torque is very, very important. It is needed to keep the bearing together and at the correct preload, so use a big torque wrench.

...or you can take it to the dealer.

Good luck. Here are some pictures that may help illustrate the difficulty:

I have a 2002 Escape and have changed my bearings. The front wheel bearings on the Escape are simple cartridge bearings, or Gen1 bearings, that are pressed onto the hub and knuckle. They are not so simple to replace. Unless you have the experience and tools, you'll need to take it to the dealer or a shop.

You will need a press and the correct press tools.
The knuckle/hub assembly needs to be removed from the vehicle.

Here's the short version:
Remove the tire/wheel.
Remove the brake caliper w/ bracket.
Remove rotor.
Remove the ABS sensor.
Remove axle nut and press the axle inwards, until loose. (sometimes easy, usual needs special tool).
Remove the strut bolts, tie rod, and the lower ball joint from the knuckle/hub assembly. Each of these connections can have it's issues.
Press the hub out of the assembly. One half of the inner race will be stuck on the hub. Use a bearing splitter to remove that half.
Remove the snap ring from the knuckle.
Press the rest of the bearing from the knuckle.
Press the new bearing into the knuckle. Press on the outer race only!
Snap ring.
Make sure the dust sheild is still in place.
Press the hub into the bearing. The bearing must be supported on the inner race only!
The point is that you must not press thru the balls in the bearing. That can cause the bearing to get brinnelled.... not good.
Reassemble the knuckle on the vehicle in reverse order. I like to put a little grease on the axle spline. The axle spline has a little helix on it... about half a degree. It's supposed to be a tight fit. The torque on the axle nut is 300Nm (about 220ft-lbs?). This torque is very, very important. It is needed to keep the bearing together and at the correct preload, so use a big torque wrench.

...or you can take it to the dealer.

Good luck.

Hub and Bearing Removal & Installation NOTE: The removal and installation of the wheel bearing and hub from the steering knuckle is only to be done with the steering knuckle removed from the vehicle
To Remove:

1. Remove the steering knuckle and hub and bearing assembly.
2. Remove a wheel lug stud from the hub flange using a C-clamp and Adapter Tool 4150A or equivalent.
3. Rotate the hub to align the removed lug stud with the notch in the bearing retainer plate. Use a proper C-clamp and adapter tool to press out one of the lug studs
   
   Rotate the hub in order to remove the lug stud
   
   
4. Rotate the hub so the stud hole is facing away from the brake caliper's lower rail on the steering knuckle.
5. Install ½ of a Bearing Splitter Tool 1130 or equivalent between the hub and the bearing retainer plate. The threaded hole in this ½ is to be aligned with the caliper rail on the steering knuckle.
6. Install the remaining pieces of the bearing splitter on the steering knuckle. Hand-tighten the nuts to hold the splitter in place on the knuckle. Proper installation of the bearing splitter
   
   
7. When the bearing splitter is installed, be sure the 3 bolts attaching the bearing retainer plate to the knuckle are contacting the bearing splitter. The bearing retainer plate should not support the knuckle or contact the splitter.
8. Place the steering knuckle in a hydraulic press, supported by the bearing splitter. Properly support the steering knuckle for hub and bearing removal
   
   
9. Position a driver on the small end of the hub. Using the press, remove the hub from the wheel bearing. The outer bearing race will come out of the wheel bearing when the hub is pressed out of the bearing.
10. Remove the bearing splitter tool from the knuckle.
11. Place the knuckle in a press supported by the press block. The blocks must not obstruct the bore in the steering knuckle so the wheel bearing can be pressed out of the knuckle. Place a driver on the outer race of the wheel bearing, and then press the bearing out of the knuckle.
12. Install the bearing splitter on the hub. The splitter is to be installed on the hub so it is between the flange of the hub and the bearing race on the hub. Place the hub, bearing race and splitter in a press. Use a driver to press the hub out of the bearing race.

To Install:

1. Use clean, dry cloth to wipe and grease or dirt from the bore of the steering knuckle.
2. Clean the rust preventative from the replacement wheel bearing using a clean, dry towel.
3. Place the new wheel bearing into the bore of the steering knuckle. Be sure the bearing is placed squarely into the bore. Place the knuckle in a press with a receiver tool, C-4698-2 or equivalent supporting the steering knuckle. Place a driver tool on the outer race of the wheel bearing. Press the wheel bearing into the steering knuckle until it is fully bottomed in the bore of the steering knuckle. NOTE: Only the original or original equipment replacement bolts should be used to mounting the bearing retainer to the knuckle. If a bolt requires replacement when installing the bearing retainer plate, be sure to get the proper type of replacement.
   
4. Install the bearing retainer plate on the steering knuckle. Install the 3 bearing retainer mounting bolts. Torque the bolts to 21 ft-lbs (28 Nm).
5. Install the removed wheel lug stud into the hub flange.
6. Place the hub with the lug stud installed, in a press supported by Adapter Tool C-4698-1 or equivalent. Press the wheel lug stud into the hub flange until it is fully seated against the back side on the hub flange.
7. Place the steering knuckle with the wheel bearing installed, in a press with special Receiver Tool MB-990799 or equivalent supporting the inner race of the wheel bearing. Place the hub in the wheel bearing, making sure it is square with the bearing. Press the hub into the wheel bearing until it is fully bottomed in the wheel bearing.
8. Install the steering knuckle and the wheel.
9. Check and/or adjust the front alignment.

About an hour a side...This is the whole job and pictures....

The hub and wheel bearing unit is serviced as a complete assembly. Replacement of the front drive hub and bearing assembly can be done without having to remove the steering knuckle from the vehicle. However, if the hub/bearing assembly is frozen to the steering knuckle, removal of the steering knuckle is required.

1. Disconnect the negative battery cable.
   
2. Remove the cotter pin from the end of the stub axle. Remove the nut lock and spring washer. With the brakes applied, loosen, but do NOT remove the axle nut and washer with the vehicle still on the ground or damage to the wheel bearing will result.
   
3. Raise and safely support the vehicle. Remove the wheel.
   
4. Remove the front brake caliper assembly from the steering knuckle assembly and support from the strut assembly using a strong piece of wire.
   
1. Remove the front brake rotor from the hub/bearing assembly.
   
2. Remove the retaining nut and washer from the halfshaft stub axle.
   
3. Remove the ABS wheel speed sensor from the steering knuckle.
   
4. Remove the 4 hub and bearing assembly mounting bolts from behind the steering knuckle.
   
5. Remove the hub and bearing assembly from the steering knuckle.
   
5. To install:
   
   1. Thoroughly clean the mating surfaces of the steering knuckle and the hub and bearing assembly of any foreign material or nicks so the surfaces are clean and smooth.
      
   2. Install the new hub and bearing assembly and tighten the mounting bolts in a crisscross pattern to 45 ft. lbs. (65 Nm). Be sure the hub and bearing assembly is seated squarely against the front steering knuckle.
      
   3. Install the disc brake rotor.
      
   4. Install the brake caliper assembly onto the steering knuckle.
      
   5. Install the axle washer and nut. Tighten but do not torque.
      
   6. Install the ABS wheel speed sensor.
      
   7. Install the wheel and lug nuts. Torque the lug nuts, in sequence, to 95 ft. lbs. (129 Nm).
      
   8. Lower the vehicle. Do NOT roll the vehicle until the axle nut has been properly torqued or damage to the front wheel bearings will result.
      
   9. With the vehicle's brakes applied, torque the axle nut to 180 ft. lbs. (244 Nm). Install the spring washer, nut lock and a new cotter pin. Wrap the cotter pin prongs tightly around the axle nut lock.
      
   10. Reconnect the negative battery cable. Check the wheel alignment.
       

The hub/bearing assembly is attached to the steering knuckle with four bolts



Removing a hub/bearing assembly




If the hub/bearing is "frozen" to the steering knuckle, separate the ball joint and lightly tap on the hub/bearing from behind




The hub/bearing assembly should free itself from the steering knuckle

About $60 a hub.

your C/V axle has a bad joint/knuckle you need to replace the axle and also check the inner wheel bearing they tend to go out a lot on that model you have to pull the axle to check it

First, disconnect the electrical connector for the ABS at the backing plate if so equipped.
Remove the axle shaft nut and then remove 3 bolts on the back side of the steering knuckle. You may have to tap the axle with a hammer a bit to drive it out of the hub taking care not to damage the axle the and the bearing may also be stuck in the steering knuckle requiring a little, or lot, of hammer action to remove it ! If your car is ABS equipped be aware that on some designs part of the ABS sensor can remain stuck inside the steering knuckle and MUST be removed prior to installing the new bearing. I simply do not remember if the 98 malibu has this design but if it does this is very important. Good luck !

wheel bearing or cv joint . remove brake caleber remove spindel nut outer bearing comes out easy inter bearing is is a little harder

What year miata?

1. Remove the steering knuckle assembly from the vehicle, as described earlier in this section.
2. For 1991 vehicles, remove the 3 dust shield fasteners and separate the shield from the assembly.
3. If equipped, remove the Anti-lock Brake System (ABS) wheel speed sensor from the knuckle.
4. Assemble wheel bearing removing tool SA9159S or equivalent using the hub driver, hub driver screw, bridge retainer and bridge. Install the tool to the knuckle and secure the assembly in a vise using the bridge as the vise contact point.
5. Hold the hub driver with a wrench and tighten the hub driver screw to remove the hub. If the inner bearing race is pulled out with the hub, remove the race with a bearing race remover. The service tool can be used by assembling the inner race puller, 2 bridge retainer plates, 2 bolts and 2 flat washers.
6. Inspect the hub at the bearing location for pitting, scoring or wear, and replace if necessary.
7. Remove the assembly from the vise and remove the wheel hub removal tools.
8. Remove the bearing retainer snapring.
9. Position the knuckle in a shop press on the knuckle support tube, and press the bearing from the knuckle with a small driver.
10. Inspect the knuckle bore for pitting, scoring, wear or corrosion. If damage cannot be easily cleaned with light sanding, the knuckle must be replaced.