ICQ>

The M46 with OD should not be an 8 speed. The OD is a planetary gear system which in non OD mode drives the output shaft of the OD via a spring pressured clutch to metal contact.

To engage the OD mode, a pair of pistons must move the clutch material away from the metal housing and engage the planetary gears. These pistons are moved using hyraulic pressure created by a pump attached to a cam that is driven by the output shaft of the transmission.

To generate enough pressure to overcome the force of the springs, the output shaft must be turning fast enough to generate the pressure required. This is around 35 to 40 MPH in 4th gear.

At any speed below this there would not be good contact between the clutch material and the output shaft of the OD. This will wear the clutch material out reyl fast and it would slip a lot beginning around 25 to 30 MPH. Like riding the clutch all the time.

The damage caused by reverse with the OD engaged is to a one way "clutch" which locks the sun gear stationary to enable the planetary gears to drive the output shaft faster than the input shaft. This type of damage can only occur if the ring gear carrier fails to slide back into "normal" position after the OD has been disengaged. It would be VERY hard to go backwards fast enough to engage the OD via hydraulic pressure.

Duane

83 245 DL LH 2.0 M46wOD 160xxx

85 245 GL LH 2.2 AW71 121xxx

The OD Guru ( Laycock Only )