Wheels - Shake/Steering Wheel Nibble
84ford17Article No. 84-5-12
VIBRATION - VEHICLE SHAKE/STEERING WHEEL NIBBLE - DIAGNOSIS AND SERVICE
- STYLED STEEL WHEELS (IRON CROSS/4Y)
FORD
1981-83 ESCORT, EXP; 1984 ESCORT, EXP, TEMPO
LINCOLN-MERCURY 1981-83 LYNX, LN7; 1984 LYNX, TOPAZ
The subject condition may occur on 1981-83 Escort/Lynx, EXP/LN7; 1984 Escort/Lynx, EXP, Tempo/Topaz with 13" x 5.0" styled steel wheels (Iron Cross and 4Y) if the tire/wheel center rib runout (CRRO) exceeds .030". Service as follows:
FIGURE 30:
1. Check the center rib runout on all four tire/wheel assemblies using procedures in the appropriate year shop manual, group 11-01.
NOTE: When measuring center rib runout, use care to determine the true wheel/tire assembly runout by ignoring "spikes" in the runout readings which last for less than 5~ of the tire circumference. These "spikes" can be caused by tire irregularities but do not affect ride. (See Figure 30 for Iron Cross and 4Y wheel identification.)
1. If runouts are less than .030" check balance, and balance if required. Refer to paragraph on checking and balancing wheels. 2a. If the runout is between .030" and .035", a reduction in runout can be obtained by reorienting the wheel on the hub (wheel studs). Remove wheel and rotate 90~ relative to wheel studs, retighten lug nuts and recheck CRRO. Repeat two more times if necessary to reduce runout to less than .030". 2b. If runouts are between .035" and .050", mark the point of highest runout on tire. Remove tire/wheel assembly from car, place on tire changer, break both bead seats but do not remove tire from wheel or rotate the tire relative to wheel. Inspect drop well for orange or green paint daub which marks low point of wheel runout (see paragraph on wheel replacement for description of markings) and mark this location on tire with an "X" (or other type of mark to distinguish it from point of high tire/wheel assembly runout). Rotate tire on wheel until mark on tire representing high point of assembly runout lines up with orange or green paint daub on wheel (it may be necessary to mark the location of the paint daub on the outside of the wheel rim). Inflate tire, mount on vehicle and check CRRO. (if runout is between .030" and .035", use procedure 2b.) If the runout cannot be reduced to less than .030" by this procedure, the wheel must be replaced. Refer to wheel replacement procedure in this article. 2c. After the runouts have been reduced to less than .030", check and/or balance wheel using the procedure in this article.
3. If runouts are greater than .050", replace wheel, Refer to paragraph on procedure for wheel replacement.
FIGURE 31:
II. The service procedure described above is summarized in the flow chart (See Figure 31).
Procedure for Checking and/or Balancing Wheels Dynamic on-car balancing is the recommended procedure for correcting balance on vehicles with this type of shake. To balance the front wheels using an on-car type balancer, it is mandatory that the front suspension lower control arm be supported as far outboard as possible to maintain the wheels in normal or nearly normal driving position.
CAUTION: DO NOT USE THE LOWER CONTROL ARMS TO RAISE THE VEHICLE.
The support must be placed under the control arms after the vehicle has been raised. Failure to support the wheels as described can result in severe overheating and/or seizure of the constant velocity joint (this results from the joint running at the very high angles created when the wheels hang free).
In addition, the engine should always be used to spin the wheels (not the power spinner). It is necessary that the proper wheel adapter designed for Escort/Lynx, Tempo/Topaz and EXP 13" wheels be used. The adapter is available from Rotunda under part number 006-01645.
CAUTION: ON FRONT WHEEL DRIVE CARS, DRIVE WHEEL SPIN SHOULD BE LIMITED TO 35 MPH AS INDICATED ON THE SPEEDOMETER.
This limit is necessary because the speedometer only indicates one half of the actual wheel speed when one drive wheel is stopped. Unless care is taken in limiting drive wheel spin, the spinning wheel can reach excessive speeds, resulting in possible tire disintegration or differential failure. Standard operating procedure may be used for rear wheel balancing.
If on-car balance equipment is not available and off-car balance equipment must be used, the procedure listed below should be followed.
FIGURE 32:
When removing the wheel to check or perform a wheel balance, mark the wheel stud position relative to the wheel and reinstall on the vehicle in this same orientation following balancing. When balancing the wheel/tire assembly, it is extremely important that the wheel is centered properly on the wheel pilot. Avoid the use of balance equipment with excessive taper on the center pilot shaft. For dynamic off-car balance, consistent wheel balance cannot be maintained using the conventional cone type wheel mounting adapter. For better balance, the optional lug adapter plate and wheel pilot collar assembly should be used. This additional equipment is necessary to assure proper wheel position on the balance equipment (Figure 32).
Procedure for Replacing Wheels
In production, the high point of the radial runout of the tire is aligned with the low point of wheel runout. This reduces the overall wheel/tire assembly runout and results in a better ride. When a new wheel is installed on the car, it must also be aligned with the tire to reduce runouts. The following procedure should be used:
1a. The service part number to be used when replacement of the 13" x 5.0" (Iron Cross) styled steel wheel is required is E2FZ-1007-A. 1b. The service part numbers to be used when replacement of the 13" x 5.0" (4Y) styled steel wheel is required are:
^ Escort/Lynx - E43Z-1007-A
^ Tempo/Topaz - E4GZ-1007-A
FIGURE 30:
1c. The low point of the wheel runout is marked by an orange or green paint daub in the area of the inboard bead seat (Figure 30).
2. Put the tire and wheel assembly from the car on the tire changer, break both bead seats but do not remove tire from wheel or rotate tire relative to the wheel.
3. Inspect the wheel drop well for orange or green paint daub and mark this location on the tire. If the tire has already been reindexed relative to the wheel Step 1 - 2b), this location will already be marked with an "X" on the tire. This will be the point of high radial runout of the tire.
4. Remove tire from the wheel and install on new wheel. When the tire is installed on new wheel, align high runout mark on tire with low runout mark on wheel and inflate.
5. Install on vehicle; check CRRO to confirm it is less than .030" and then balance.
PART NUMBER PART NAME CLASS
E2FZ-1007-A Wheel A
E43Z-1007-A Wheel B
E4GZ-1007-A Wheel B
ARTICLES SUPERSEDED: 81-7-7; 82-2-8
WARRANTY STATUS: Reimbursable within the provisions of the Warranty and Policy Manual.
DLR. CODING: Basic Part No. 1007 Code: 67