Speedtech 9" Ford Gear Break In - Manual

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Nov 26, 2013
9” Ford 3 rd
Member Break-in Instructions
Gear Lube
Using Premium 85-140 weight or better gear lube, fill the gear case to proper level. To
protect the safety and working life of your gear set periodically inspect for leakage, oil
level, vent tube for cleanliness and function, and top off oil as needed.
New Gear Break-In
New Bearings and high ratio gear sets can cause excessive heat build up. High heat can soften
gear teeth surfaces. Proper break-in will prevent this. On initial run, drive lightly for 15 to 20
minutes then stop to allow differential to cool completely for 20 to 25 minutes. Avoid heavy
acceleration and vary speeds every 5 to 10 minutes while driving on highways. Drive
conservatively and do not drive more than 50 miles at a time without allowing a cool cycle
during the first 500 miles following installation. After completing initial break-in, change gear oil
at 500 miles. Small metal particles are normal and gear oil will typically be black. Excessive
metal in gear oil should be reviewed by a competent differential mechanic to ensure safety of
internal parts.
Speedtech Performance USA LLC
2884 S River Rd. Bldg. A St. George, UT 84790
1-435-628-4300 www.speedtechperformance.com