Drivelines Northwest, Inc. - Troubleshooting

This page was designed to help you determine probable causes for common driveline problems and guide you to the best corrective action. For serious problems, we recommend that you call us for assistance in determining the cause and the best corrective action.

Symptoms have been categorized into 3 groups. Find the symptom that closely matches what you are experiencing and click on it to find the probable cause and probable corrective action.

Vibration Problems		Seizures, Breaks and Failures
	General Vibrations		Low Mileage U-Joint Failure
	Low Gear Shudder		Repeat U-Joint Failure
	Vibrations in Short Speed Ranges Under Full Drive or Full Coast		End Galling of Cross Trunnion and Bearing Cup
	Vibrations Under Light Loaded Conditions		Bearing Race O.D. Seizure in Yoke Cross Holes
Abnormal Wear			lip Spline Seizures
	Slip Spline Galling		Slip Spline Shaft or Tube Broken in Torsion
	Slip Spline O.D. Wear at Extremities and at 180°		Shaft Broken in Bending
	Frettage (Also: False Brinelling, Wear Oxidation, Friction Oxidation, and Chaffing Fatigue)		Tube Split in Longitudinal Seam Weld
			Tube Circle Weld Failure
			Yoke Broken in Hub
			Yoke Broke at Ear Tip
			Broken Cross or Cups
	Download the entire guide in a PDF file (121kb)		Needle Rollers Brinelled into Cups and Cross Trunnion
	Requires Adobe Acrobat Reader Available Free		Shaft Support Brg. Failure
			Shaft Support Rubber Insulator Failure
			Transmission Extension Bell Housing and Clutch Housing Failures

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Vibration Problems - Probable Causes & Corrective Action
General Vibrations
Probable Causes		Probable Corrections
Inadequate torque on cap screws retaining brg. plate		Torque bearing retention to spec.
Worn universal joints		Replace U-joint kits.
Continuous running u-joint angles - too large		Reduce U-Joint's continuous running angles.
Unequal u-joint angles		Shim drivetrain components to equalize U-joint angles.
Driveshaft balance and straightness		Straighten and balance.
Damaged driveshaft tube		Straighten and balance or replace tube.
Runout on drive and driven support shafts		Check with transmission or axle manufacturer...Replace shaft bearing.
Excessively loose u-joint for operating speed and length		- Install two piece driveshaft with shaft support bearing. - Straighten and balance. - Check U-joint flex effort for looseness. - Torque bearing retention to spec.
Loose O.D. fit on slip spline		Replace.
Driveshaft too long for speed - operating in critical		- Install two piece driveshaft with shaft support bearing. - Use larger diameter tube.
Driveshaft weight not compatible with engine - transmission mounting		- Install two piece driveshaft with shaft support bearing. - Revise power plant mounting scheme.
Driveshaft yoke phasing		Check O.E.M. maintenance manual or alignment arrows on slip yoke and male slip shaft for correct yoke phasing.
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Low Gear Shudder
Probable Causes		Probable Corrections
Secondary couple load reaction at shaft support brg.		- Reduce U-Joint's continuous running angles. - Shim drivetrain components to equalize U-joint angles. - Check O.E.M. maintenance manual or alignment arrows on slip yoke and male slip shaft for correct yoke phasing. - If 2 piece-3JT driveshafts...Adjust shaft lengths to 50-50 or 40-60 split. - Reposition shaft support bearing.
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Vibrations in Short Speed Ranges Under Full Drive or Full Coast
Probable Causes		Probable Corrections
Torsional excitation		- Reduce U-Joint's continuous running angles. - Shim drivetrain components to equalize U-joint angles.
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Vibrations Under Light Loaded Conditions
Probable Causes		Probable Corrections
Inertia excitation		Reduce U-Joint's continuous running angles.

Abnormal Wear - Probable Causes & Corrective Action
Slip Spline Galling
Probable Causes		Probable Corrections
Contamination (Abrasion)		Check components. If serviceable...Clean and relubricate per lube specs. If not serviceable...Replace.
Lubricating film breakdown		- Lubricate u-joints according to manufacturer specifications. - Use Hi-Temp grease. - Check components. If serviceable...Clean and relubricate per lube specs. If not serviceable...Replace.
Slip member working in extreme extended position		Increase driveshaft assembly length. Position slip spline head towards U-joint.
Male spline head engagement length too short for application		- Check for male slip member with longer spline. - Design is inadequate for application.
Excessive torque load for u-joints and driveshaft size		Replace with higher capacity U-joint and driveshaft.
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Slip Spline O.D. Wear at Extremities and at 180°
Probable Causes		Probable Corrections
Slip member working in extreme extended position		Increase driveshaft assembly length. Position slip spline head towards U-joint.
Excessive loose O.D. fit		If normal wear...Replace.
Male spline head engagement length too short for application		- Check for male slip member with longer spline. - Design is inadequate for application.
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Frettage (Also: False Brinelling, Wear Oxidation, Friction Oxidation, and Chaffing Fatigue)
Probable Causes		Probable Corrections
Contamination (Abrasion)		- Lubricate u-joints according to manufacturer specifications. - Check components. If serviceable...Clean and relubricate per lube specs. If not serviceable...Replace. - If normal wear...Replace.
Lubricating film breakdown		- Lubricate u-joints according to manufacturer specifications. - Use Hi-Temp grease. - Replace with higher capacity U-joint and driveshaft. - Check components. If serviceable...Clean and relubricate per lube specs. If not serviceable...Replace.
No u-joint operating angle		Re-align for a minimum 1° running angle.
Long shaft with loose u-joint thrust fit and unbalance		- Install two piece driveshaft with shaft support bearing. - Straighten and balance. - Check U-joint flex effort for looseness. - Torque bearing retention to spec.
Roller lock		- Yoke deflections under load...Use larger joint. - Replace.
Roller skewing		- Yoke deflections under load...Use larger joint. - Replace roller lock assembly. - Replace.
Excessive u-bolt torque on retaining nuts - pinching rollers		Torque bearing retention to spec.
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Seizures, Breaks and Failures - Probable Causes & Corrective Action
Low Mileage U-Joint Failure
Probable Causes		Probable Corrections
Lack of lubrication		Lubricate u-joints according to manufacturer specifications.
Inadequate initial lubrication		Lubricate u-joints according to manufacturer specifications.
Inadequate grease quality for application		- Lubricate u-joints according to manufacturer specifications. - Use Hi-Temp grease.
Inadequate relube cycles for application environment		Lubricate u-joints according to manufacturer specifications.
Failure to lubricate properly		Lubricate u-joints according to manufacturer specifications.
Defective or worn seals		If new kit...replace seals. If used...Replace complete kit.
Continuous operation at high angle - high speed		Reduce U-Joint's continuous running angles.
Excessive continuous running load		Replace with higher capacity U-joint and driveshaft.
End galling of cross trunnion and bearing cup		- Lubricate u-joints according to manufacturer specifications. - Reduce U-Joint's continuous running angles. - Use Hi-Temp grease. - Check U-joint flex effort. If sticks, binds or grabs...Replace U-joint kit. If still sticks, binds or grabs...Check yokes for span, lug squareness, cross hole alignment, etc. Replace as needed.
Excessive u-bolt torque on retaining nuts - pinching rollers		Torque bearing retention to spec.
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Repeat U-Joint Failure
Probable Causes		Probable Corrections
Lack of lubrication		Lubricate u-joints according to manufacturer specifications.
Inadequate initial lubrication		Lubricate u-joints according to manufacturer specifications.
Inadequate grease quality for application		- Lubricate u-joints according to manufacturer specifications. - Use Hi-Temp grease.
Inadequate relube cycles for application environment		Lubricate u-joints according to manufacturer specifications.
Failure to lubricate properly		Lubricate u-joints according to manufacturer specifications.
Defective or worn seals		If new kit...replace seals. If used...Replace complete kit.
Yoke distortion due to initial failure		- Yoke deflections under load...Use larger joint. - Replace yoke if distorted.
Continuous operation at high angle - high speed		Reduce U-Joint's continuous running angles.
Excessive continuous running load		Replace with higher capacity U-joint and driveshaft.
End galling of cross trunnion and bearing cup		- Lubricate u-joints according to manufacturer specifications. - Reduce U-Joint's continuous running angles. - Use Hi-Temp grease. - Check U-joint flex effort. If sticks, binds or grabs...Replace U-joint kit. If still sticks, binds or grabs...Check yokes for span, lug squareness, cross hole alignment, etc. Replace as needed.
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End Galling of Cross Trunnion and Bearing Cup
Probable Causes		Probable Corrections
Continuous operation at high angle - high speed		Reduce U-Joint's continuous running angles.
Contamination (Abrasion)		- Lubricate u-joints according to manufacturer specifications. - Check components. If serviceable...Clean and relubricate per lube specs. If not serviceable...Replace. - If normal wear...Replace.
Lubricating film breakdown		- Lubricate u-joints according to manufacturer specifications. - Use Hi-Temp grease.
Excessive thrust fit		Check U-joint flex effort. If sticks, binds or grabs...Replace U-joint kit. If still sticks, binds or grabs...Check yokes for span, lug squareness, cross hole alignment, etc. Replace as needed.
Yoke cross hole alignment		Check U-joint flex effort. If sticks, binds or grabs...Replace U-joint kit. If still sticks, binds or grabs...Check yokes for span, lug squareness, cross hole alignment, etc. Replace as needed.
Yoke lug face squareness		Check U-joint flex effort. If sticks, binds or grabs...Replace U-joint kit. If still sticks, binds or grabs...Check yokes for span, lug squareness, cross hole alignment, etc. Replace as needed.
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Bearing Race O.D. Seizure in Yoke Cross Holes
Probable Causes		Probable Corrections
Frettage corrosion due to yoke working under load		No immediate fix. Anti-seize lubricant on bearing O.D. will initially help.
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Slip Spline Seizures
Probable Causes		Probable Corrections
Lack of lubrication		Lubricate u-joints according to manufacturer specifications.
Inadequate initial lubrication		Lubricate u-joints according to manufacturer specifications.
Inadequate grease quality for application		Lubricate u-joints according to manufacturer specifications.
Inadequate relube cycles for application environment		Lubricate u-joints according to manufacturer specifications.
Failure to lubricate properly		Lubricate u-joints according to manufacturer specifications.
Contamination (Abrasion)		Check components. If serviceable...Clean and relubricate per lube specs. If not serviceable...Replace.
Lubricating film breakdown		- Lubricate u-joints according to manufacturer specifications. - Use Hi-Temp grease. - Check components. If serviceable...Clean and relubricate per lube specs. If not serviceable...Replace.
Galling (Adhesive wear)		- Lubricate u-joints according to manufacturer specifications. - Use Hi-Temp grease. - Replace with higher capacity U-joint and driveshaft. - Check components. If serviceable...Clean and relubricate per lube specs. If not serviceable...Replace.
Slip member working in extreme extended position		Increase driveshaft assembly length. Position slip spline head towards U-joint.
Excessive torque load for u-joints and driveshaft size		Replace with higher capacity U-joint and driveshaft.
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Slip Spline Shaft or Tube Broken in Torsion
Probable Causes		Probable Corrections
Excessive torque load for u-joints and driveshaft size		- Replace with higher capacity U-joint and driveshaft. - Use larger diameter tube.
Improper slip spline shaft neck heat treatment		Replace.
Inadequate radius at slip spline shaft neck runout - stress riser		- Replace with higher capacity U-joint and driveshaft. - Design is inadequate for application.
Tube size inadequate		- Replace with higher capacity U-joint and driveshaft. - Use larger diameter tube.
Defective or worn part		Replace.
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Shaft Broken in Bending
Probable Causes		Probable Corrections
Driveshaft too long for operating speeds		- Install two piece driveshaft with shaft support bearing. - Use larger diameter tube.
Bending fatigue due to secondary couple loads		Reduce U-Joint's continuous running angles.
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Tube Split in Longitudinal Seam Weld
Probable Causes		Probable Corrections
Defective or worn part		Replace.
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Tube Circle Weld Failure
Probable Causes		Probable Corrections
Excessive torque load for u-joints and driveshaft size		- Replace with higher capacity U-joint and driveshaft. - Use larger diameter tube.
Defective circle weld		Replace.
Balance weight too close to circle weld		Replace.
Balance weight located in apex of weld yoke lug area		Replace.
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Yoke Broken in Hub
Probable Causes		Probable Corrections
Excessive torque load for u-joints and driveshaft size		Replace with higher capacity U-joint and driveshaft.
Bending fatigue due to secondary couple loads		Reduce U-Joint's continuous running angles.
Inadequate hub and radius for application		Design limitation due to axle's or transmission shaft's requirement.
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Yoke Broke at Ear Tip
Probable Causes		Probable Corrections
Defective forging or casting		Replace.
Missing yoke lug interference at full jounce and rebound		- Reduce U-Joint's continuous running angles. - Use wide angle yokes.
Improper shaft length and slip		Check installed length. Adjust driveshaft length to provide proper slip conditions.
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Broken Cross or Cups
Probable Causes		Probable Corrections
Excessive torque load for u-joints and driveshaft size		Replace with higher capacity U-joint and driveshaft.
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Needle Rollers Brinelled into Cups and Cross Trunnion
Probable Causes		Probable Corrections
Excessive torque load for u-joints and driveshaft size		Replace with higher capacity U-joint and driveshaft.
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Shaft Support Brg. Failure
Probable Causes		Probable Corrections
Lack of lubrication		If normal wear...Replace.
Inadequate initial lubrication		Replace.
Defective or worn seals		If normal wear...Replace.
Contamination (Abrasion)		If normal wear...Replace.
Defective or worn part		If normal wear...Replace.
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Shaft Support Rubber Insulator Failure
Probable Causes		Probable Corrections
Shaft support brg. misaligned - interference with slinger		Re-align mounting bracket to frame cross member and eliminate interference.
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Transmission Extension Bell Housing and Clutch Housing Failures
Probable Causes		Probable Corrections
Worn universal joints		Replace U-joint kits.
Continuous running u-joint angles - too large		Reduce U-Joint's continuous running angles.
Unequal u-joint angles		Shim drivetrain components to equalize U-joint angles.
Driveshaft balance and straightness		Straighten and balance.
Damaged driveshaft tube		Straighten and balance or replace tube.
Runout on drive and driven support shafts		Check with transmission or axle manufacturer...Raplace shaft bearing.
Excessively loose u-joint for operating speed and length		- Install two piece driveshaft with shaft support bearing. - Straighten and balance. - Check U-joint flex effort for looseness. - Torque bearing retention to spec.
Loose O.D. fit on slip spline		Replace.
Driveshaft too long for speed - operating in critical		- Install two piece driveshaft with shaft support bearing. - Use larger diameter tube.
Driveshaft weight not compatible with engine - transmission mounting		- Install two piece driveshaft with shaft support bearing. - Revise power plant mounting scheme.
Driveshaft yoke phasing		Check O.E.M. maintenance manual or alignment arrows on slip yoke and male slip shaft for correct yoke phasing.
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