F 350 4WD Pickup V8-351 5.8L VIN H EFI (1997)
Tires: Customer Interest
Rear Brakes - Vibration/Shudder When Applying Brakes
Article No.
98-5A-25
03/18/98
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BRAKES - REAR VIBRATION/SHUDDER WHEN
APPLYING BRAKES - SERVICE TIPS
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SHUDDER - REAR - WHEN APPLYING BRAKES -
SERVICE TIPS
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VIBRATION - REAR - WHEN APPLYING BRAKES -
SERVICE TIPS
LIGHT TRUCK:
1994-97 F-250 HD, F-350
ISSUE:
A vibration or shudder may be felt during braking on some vehicles. This may be caused by heating of the rear brake drums causing surface roughness
and/or distortion of the drums.
ACTION:
The following provides a list of diagnostic Service Tips to help resolve vibration/shudder concerns induced by the rear brakes.
SERVICE TIPS
1.
Determine if the vibration/shudder is being caused by the rear brakes by making a light stop from about 80-55 km/h (50-35 mph) using the parking
brake. In order to do this, hold the release handle out while depressing the parking brake with the left foot. If the vibration/shudder continues to
occur during the parking brake application, continue with the following Steps.
2.
Check the vehicle for loose or over-tightened lug nuts.
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Inspect the wheel studs for damage and replace if needed
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Inspect the wheel stud holes to see if they are elongated. If so, replace the wheel(s)
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Retorque the lug nuts on the vehicle using Accutorq(R) lug nut socket per TSB 98-5A-4. If this tool is not available then retorque the lug nuts
with a standard torque wrench to 190 N.m (140 lb-ft) in a double star pattern
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Check tire pressures to make sure they are at the correct setting
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Reverify concern
3.
If the concern is still present and the vehicle has Ford original equipment tires/wheels, check the tires and wheels for excessive radial and lateral
runouts by referring to the appropriate Service Manual, Section 04-04. Service as required.
4.
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If the vehicle has aftermarket wheels and/or tires, replace with Ford original equipment wheels/tires
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If the condition is corrected, explain to owner the effect aftermarket wheels/tires have on vibration/shudder
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If the condition is still present, proceed to Step 5
5.
Remove the rear brake drums and inspect for axle lube leaks. If present, service the rear wheel seals and brakes as needed. For cold weather
operation in sub-zero temperatures see TSB 98-5A-27. If no leaks are present, proceed to Step 6.
6.
Check adjustment of the rear parking brakes and routing of the cables to be sure excess drag does not exist in the rear brakes. Refer to TSB
98-5A-35 for correct rear parking brake cable routing. If the vehicle is a Crew Cab model, secure the cable midway in the routing to prevent
excessive bounce/movement of the cable while driving.
7.
Inspect the rear drums for signs of excess heating including cracking and glazing of the braking surfaces. Resurface the drums if glazing is present.
Replace the drums if any visual cracks/damage appear or if they exceed the maximum diameter listed on the rim of the brake drum.
