Rear Wheel Bearing and Hub Replacement
Rear wheel bearing failure can be detected by a rumble, grinding or humming noise. This can be best heard when coasting in neutral with the engine off. This is a practice I would suggest doing once a year, just to keep tabs on what is normal and abnormal. Bad bearings can also be detected by a "loose" feeling in car handling. To further check for bad bearings, lift tires off the ground, grab the tire at the top and bottom and attempt to rock the tire in and out. If not too bad, you may only detect a slight thump noise. If any play is detected, first check that the spinners are tight, the wheel pins are tight and that the center axle nut is tight. If you still detect play at the rear wheels, the bearings need to be replaced. Front wheels are not addressed in this article.
If caught early, bearing replacement may be all that is necessary, however, it it was not caught early, rear hub damage is also possible. This article will cover both rear bearing and hub replacement.
Depending on your car number and your own capabilities, you may be able to do all of the repair yourself or where special tools, machining or presses are required you may need the help of your local rear axle repair and/or machine shop.
This article is written for cars in the late 2000 range that came with a Dana rear end. If you car is of a different vintage, there may be several differences that you will notice and may need to adjust the repair process.
Because I do not have the special tools and presses necessary to press off and reinstall wheel bearings, my process is to remove the wheel hubs with axle shafts and take the complete assembly to a local axle shop for repair. That is the process that will be addressed here.
1. Lift and secure the car with the rear wheels off the ground.
2. Remove the rear wheels, wheel pins and spinner adapters. No need to remove the wheel nut. On this vintage car, the hub is a tight press onto the axle and it can not be removed without the proper press. Leave that for the axle shop.
3. Remove the brake caliper and set it back on the lower A-arm. Do not leave it hanging from the brake line as this may damage or kink the brake line
WARNING. While the brake caliper is off the brake rotor, do not touch the brake pedal. This will blow the brake pistons out of the calipers, draining the brake fluid. Also on this vintage of car that has the integral parking brake, do not attempt to engage the parking brake handle.
4. Remove the center, aluminum spinner adapter centering ring. It is a slip fit over the wheel hub, but may need some persuasion to get it off. tapping a sharp chisel down behind it or applying a little heat may be necessary.
5. Remove the brake rotor. It just slips over the wheel studs and hub center, but like the centering ring, may need some persuasion to get it off. For the rotor, tap on the back side with a rubber mallet, working your way around the rotor, so it pulls straight off.
6. Pop the inner axle stub out of the differential. To do this, push a large screw driver or pry bar between the stub and the differential case. Pry in a manner where the tip of the screw driver pushes the stub out using the differential case as the fulcrum. Do not pry in the opposite direction as this may damage the axle seal that is pressed into the differential case.
7. Remove the upper A-Arm bolt. There are multiple spacers/shims on this bolt to secure the knuckle in it's proper position. Pay particular attention to the location of all spacers/shims. This assembly must go back together exactly as it came apart to maintain proper rear end alignment.
8. Loosen the forward, lower A-Arm pivot bolt.
9. Remove the Allen head set screw that is located in the Knuckle, half way between the front and rear pivot bolts. This screw engages the pivot shaft about 1/4" and must be backed out so you can drive the pivot shaft out.
NOTE - This is specific to newer cars. On older cars, you remove the front and rear pivot bolts at the lower A-Arm and the Knuckle will come loose. Also on the older cars there are loose shims between the A-Arm and Knuckle. Pay close attention to the location/number of these shims so you can get it properly shimmed on re-assembly.
10. With the forward pivot bolt backed out about 1/2", tap on it with a lead hammer to begin to drive the pivot shaft out. If the shaft does not move, it may be stuck due to lack of lubricant. You may need a bigger hammer.
11. Remove the forward pivot bolt and use progressively longer drifts to tap the shaft out. A drift can be a piece of pipe or a bolt, just as long as it is not so small in diameter to engage and damage the pivot bolt threads. A 3/8" bolt, inserted head first works nicely. The shaft does not need to be completely removed, just removed far enough to disengage the knuckle.
12. Remove the knuckle, hub and axle as an assembly
13. Repeat for the opposite side
You will not know the extent of the damage until the hub and bearings have been disassembled. At a minimum you will need new bearings. The proper bearings are Ford Racing part number M-1215-A. If the damage is severe, you may also need new hubs. The proper hub is Ford Racing part number M-1109-A. However, where the bearing is a direct replacement, using the M-1109-A hub will require machine work.
M-1109-A hub modifications.
1. The lugs need to be either cut off to the same length as the originals, to allow for wheel pin assembly, or, if the original lugs are in good shape, you can have them pressed out of the original hub and into the new.
2. The M-1109-A hub is a little larger in diameter that the original and will not fit inside the rotor hat. This may not be true for all vintage of cars, but is for the series addressed in this article. For this installation, the hub O.D. must be machined down to 5.43" Dia. from 5.50" Diameter
Brake rotor hat modifications
1. The M-1109-A hub has a larger pilot, requiring the hat pilot hole to be enlarged to 2.75" Dia
2. You must also add a chamfer of about .080" to the pilot hole so it does not interfere with the fillet on the hub.
Centering ring modification.
Because of the hub pilot diameter is larger, the original centering ring will not fit.
Option 1. Use no ring and allow the spinner adapter to center with the wheel pins.
Option 2. If you feel you need a centering ring, you will have to machine one that pilots inside of the Hub and then steps out to center the spinner adapter. You can not simply machine out the original aluminum centering ring because it would only be .080" thick. Not substantial enough to be of any aid.
Not an option - You can not machine the new hub pilot down to the original pilot diameter because the new hub pilot I.D. is too large. You could do a combination of machining down the hub pilot and machining out the original centering ring, but that seems like the long way to go. Option 2 would seem easier, but then again, you should be fine with Option 1
Reassembly is just a reverse of disassembly. A few worthy notes.
1. Makes sure the inner stubs are fully engaged into the differential. Tapping the inner stubs with a 3' length of 2x4 and a lead hammer helps. Be sure to not pound on the CV boot.
2. When reassembling the the brake calipers, it is suggested you apply red thread locker to the bolt threads.
3. The shop that rebuilt the axles should have properly tightened the wheel nut. but you may want to recheck. 280 ft. lbs is suggested. On cars 1529-2200, there should be double nuts because on that series of cars, the axle to hub spline is a slip fit, not a press fit.
4. To tighten the wheel pins, slip a pin alignment tool (available from http://www.trigowheels.com ) on till flush with the end of the pins and torque to 80 ft lbs. Tighten in a sequence of every other lug in 3 steps, 40/60/80 ft lbs. Do not remove the tool until all lugs are all tight.
5. Test the brakes before lowering the car. If you had to back the pads off to reassemble, the first stroke of the pedal may be longer than normal.
Below are photos of old and modified parts
Old Hub
New Hub before any mods
New Hub Mod's.
Rotor Mod's.
New hub installed with original (shorter) lugs and machined to 5.43" O.D.