Driveline - Moderate To Severe Vibration
86ford22 Article No. 86-4-14VIBRATION - DRIVELINE - DIAGNOSIS AND SERVICING
MERKUR 1985-86 XR4Ti
This article provides instructions for aligning and centering the (two-piece) driveshaft to resolve a driveline vibration as described below.
1. A severe but temporary driveline vibration after the vehicle has been parked in extreme cold temperatures for an extended period. This symptom will go away after 3 to 4 miles of driving but will recur when the vehicle is again parked in extreme cold for an extended period.
2. Driveline vibration that is much less severe than condition 1, but can be felt in the floor of the car after the vehicle is warm (or in ambient temperatures above freezing). This driveline vibration is most often felt when driving away from a full stop but on some vehicles can be felt at highway speeds.
Driveline vibration in both driving conditions is caused by improper driveline alignment.
NOTE: Driveline alignment on the XR4Ti is measured at the rubber joint/damper (guibo joint) at the front of the driveshaft. Any misalignment is measured as runout at the guibo joint.
Figure 32:
To check and set driveshaft guibo joint runout, a dial indicator that indicates off the back of the gauge (such as Starrett Model No. 196B1) Special Tool Number TOOL-4201-C, must be used with a 1/4" x 1/4" trunnion and a fabricated fixture which mounts the indicator to the driveshaft. The fixture must be fabricated as described in Figure 32. To perform alignment of the driveline guibo joint, the following procedure must be followed.
A. Raise the vehicle in such a manner that the rear wheels are free to rotate. (Transmission in neutral and the emergency brake released.)
Figure 33:
B. Verify the vehicle is properly assembled with a spacer (quantity of 2, one on each side) between the body and the driveshaft center bearing (as shown in Figure 33).
C. After checking that the vehicle is properly shimmed, check/set the runout of the guibo joint as follows:
Figure 32:
Figure 33:
1. Using the dial indicator tool (fabricated as detailed in Figure 32) clamp the tool to the driveshaft as shown in Figure 33 and determine the driveshaft angularity by measuring the rubber guibo joint rotational runout while rotating the rear wheels. Vertical alignment can be determined by the difference in dial gauge readings between the 6:00 and 12:00 o'clock positions as described on the sketch. Horizontal alignment is the difference in the dial gauge readings between 3:00 and 9:00 o'clock positions.
2. If either the vertical or horizontal misalignment exceeds 0.005 inch on the dial indicator, an adjustment must be made to make the alignment as close to .000" as possible.
a. For vertical alignment adjustment: With the dial indicator placed on a bolt end as shown at the 6:00 o'clock position (after zeroing the gauge at 12:00 o'clock) push up and down on driveshaft near the center bearing while watching the dial reading to determine if the center bearing is to be adjusted upwards or downwards.
1. If center bearing is to be adjusted upwards, remove the washer spacers from between the center bearing and the body and refasten the bearing to the body.
2. If center bearing is to be adjusted downwards, add to the existing washer spacer on each side an additional 3/16" thick flat washer.
b. For horizontal alignment adjustment: With dial indicator at the 9:00 o'clock position (after zeroing out at 3:00 o'clock) push shaft (near center bearing) from side to side while observing the dial reading to determine direction the bearing is to be moved to align the shaft. Loosen the center bearing attachment bolts and move the bearing in this direction approximately 1/8 inch. Snug bearing bolts and check alignment again. Re-align if required.
3. With vertical and/or horizontal adjustments made and center bearing bolts snug, re-measure the alignmentt to verify that both vertical and horizontal readings are less than 0.005 inches on the dial gauge. Remove gauge.
4. Tighten center bearing bolts to 18-23 N-m (13-17 ft.lbs.).
5. Lower vehicle.
OTHER APPLICABLE ARTICLES: None
WARRANTY STATUS: Reimbursable within the provisions of the Warranty and Policy Manual.
OPERATION: SP4602A86 - Time to fabricate special tool. Use only once.
TIME: 1.0 Hr.
OPERATION: SP4602B86 - Set driveline.
TIME: 0.6 Hr. DLR. CODING: Basic Part No. 4602 - Code: 67