Are they or are they not limited slip ???
KaptnKA
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Moderators: FORDification, 70_F100
Now that is my kind of science!!averagef250 wrote:On a straight stretch of dry back country road-
If it's auto- Place gear selector in reverse, push accelerator pedal swiftly to full, count "one thousand one, one thousand two" then without decreasing accelerator position rapidly move gear selector from down to it's limit which will be "1". Note engine tone, upon noticeable valve float sound bump gear selector upward one notch to "2". When speedometer indicates approximately 45 MPH ease off accelerator and gently apply brake.
If it's stick- With transmission in 2nd gear and clutch disengaged bring engine RPM's to approximately 3500. Rapidly release clutch pedal while moving accelerator to full. Note engine tone, upon noticeable valve float sound simultaneously ease off accelerator while depressing clutch. Shift transmission to nuetral.
Turn around and inspect tire marks on pavement. Two equal length tire marks indicate a Powerlock limited slip. Two marks with the driver's tire mark noticeably longer than the passenger tire mark indicates a new Trac-loc limited slip. One tire mark indicates an open differential or a Trac-loc more than a month old.
If you have determined you have a limited slip Dana 60 differential, but cannot determine if it's a Powerlock or a Trac-loc place the driver's side tire off the pavement in gravel and the other on pavement and repeat testing procedure. If there's a tire mark on the asphalt you have a powerlock. Lack of a tire mark indicates a trac-loc.