Does an AOD transmission have a vacuum modulator?
Does an AOD transmission have a vacuum modulator?
The AOD is a true hydromechanical 4-speed automatic transmission controlled by a manual shifter and throttle valve (TV) cable. There is no vacuum modulator or kickdown linkage with the AOD as we see with the older C3, C4, C6, and FMX transmissions; only the lone TV cable.
How does a 4R70W transmission work?
With the AODE/4R70W, throttle tip-in while you’re in overdrive disengages the converter clutch, which enables torque multiplication with improved acceleration without having to switch from one input shaft to another. With the AODE and 4R70W it all happens via one input shaft.
How to change the AOD transmission in a Ford?
Disconnect the driveshaft, shift, and kickdown linkages. Have a solid means of support beneath the transmission. Remove the dust cover to get at the torque converter and flexplate. Remove the torque converter fasteners with a 5/8-inch socket. Rotate the engine crankshaft to get at hard-to-reach fasteners.
What causes a transmission to shift from OD to OD?
If your transmission shifts from first to second, seems to hold second longer than normal, and then finally neutrals out completely at the point where it would normally shift to OD then the most likely cause is a damaged Direct Clutch Pack. This would require transmission removal and disassembly to repair.
Why does my AOD transmission shift to full throttle?
There are a few common causes for this. The first is a disconnected or missing TV linkage. If the TV linkage is disconnected the transmission should default to full TV pressure which will make the transmission shift as if it were at Wide Open Throttle all the time.
Why does my AOD transmission stick in high pressure?
Often during the adjustment procedure of the aftermarket TV cable the TV valve inside the transmission gets pushed in farther than the factory cable would allow. This causes the TV valve to stick in the high pressure position even when the linkage returns to the idle position.
If your transmission shifts from first to second, seems to hold second longer than normal, and then finally neutrals out completely at the point where it would normally shift to OD then the most likely cause is a damaged Direct Clutch Pack. This would require transmission removal and disassembly to repair.
What’s the throttle point on an AOD transmission?
It sounds like you don’t have a TV cable hooked to the transmission. If the TV cable is not connected the transmission will default to full TV pressure. If TV pressure is full shifts will only occur at the wide open throttle shift point, which is usually around 4900 RPM.
Often during the adjustment procedure of the aftermarket TV cable the TV valve inside the transmission gets pushed in farther than the factory cable would allow. This causes the TV valve to stick in the high pressure position even when the linkage returns to the idle position.
