Transmission Troubleshooting

1. Preliminary Inspection

a. Personal Observation – look for signs of misuse such as broken mounts, fittings or brackets; check airlines.
b. Question the Owner or Operator – gather information on operating conditions and vehicle use, on history of problem, and on shifting characteristics if affected.
c. Gather History of Unit – including maintenance and lubrication procedures, past failures, and mileage or hours of use.

snubbed clutching gear teeth

Snubbed Clutching Gear Teeth

2. Disassemble Transmission

a. Keep oil sample for impurities, check if needed.
b. During disassembly, check for incorrectly installed parts, missing parts, and nongenuine parts.
c. Clean and inspect each piece closely

3. Determine Type of Failure.

Fretted Splines

Fretted Splines

Broken Synchronizer Pins

Broken Synchronizer Pins

Input Spline Wear

Input Spline Wear

Worn Yoke Bar

Worn Yoke Bar

4. Determine and correct Cause of Failure.

To Use Guideline Chart

The Troubleshooter’s Guideline Chart is used to locate and correct transmission problems.
To use the guideline:

1) Locate the transmission problem in the left hand column;

2) Trace line horizontally across the page until a rectangle with a number in it is reached;

3) Trace up vertical column to find a possible cause. The number in the intersection of the vertical and horizontal lines tell which corrections to use;

4) Possible corrections are listed below.

There may be more than one possible cause and possible correction for each problem

Possible Corrections

1. Instruct driver on proper driving techniques.
2. Replace parts (after trying other listed possible
3. Loosen lock-screw and retighten to proper torque.
4. Look for resultant damage.
5. Smooth with emery paper.
6. Reset to proper specifications.
7. Install missing parts.

8. Check airlines or hoses.
9. Tighten part.
10. Correct the restriction.
11. Recheck timing.
12. Clean part.
13. Apply thin film silicone.
14. Apply sealant

For further assistance, please contact our transmission support specialists at (407) 872-1901.

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*See warranty. All other warranties are that of the manufacturer.

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