Editing AMC V-8s (section)
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===Automatic transmissions=== AMC used GM hydramatic transmissions in 1957 switching in the '58 model year to "Flash-O-Matic" units manufactured primarily by Warner Gear Division of Borg Warner. Only manual transmissions were used in the 1956 Specials. AMC called the GM automatic "Flashaway" and the Borg-Warner transmission "Flash-O-Matic". It's a three speed cast iron case Borg-Warner Model 8 with a vacuum modulator valve. The column shift quadrant will read P-R-N-2-D-1-L. The 1 and 2 are small. A dash mounted push-button shifter mechanism was used in the Rambler 6 and Ambassador from 1958-'62. The American models used a column shifter. The push-buttons were marked N-R-D2-D1-L, with a Park lever under the dash. P-R-N are self explanatory. In D2 the transmission will act like a two speed. It starts in second gear and shifts to third, downshifts only to second. This was mainly used for slippery conditions such as driving in snow or ice. Using second gear prevented excessive wheel spin. Many people think they have a two speed transmission because this is the third forward position on the transmission. Slip it down to D1, however, and you'll find the missing gear! In D1 the trans shifts from first through third and back down. L (low) is first gear only, no up shifts. The trans can safely be shifted into Low at any speed. As a safety feature the trans will not shift down until it has reached a safe speed to do so. If in third it will got to second, then down to first once a safe speed is reached. It will not shift back up until shifted into D1 or D2. To manually shift through the gears start in L, shift up to D1 then as soon as the trans shifts, go back to L. It won't downshift if accelerating. When ready for third gear go back to D1. 1965-'66 models used a throttle valve cable instead of a vacuum modulator to control internal pressure. This is the M-10, internally similar to the M-8 except for the TV cable and valve body. The cable '''must''' be connected for the transmission to work correctly! Otherwise it will burn up like a cable equipped GM TH700R4 or a Chrysler transmission without the "kick-down" linkage connected. On the '67-'71 "Shift Command" versions, an electric solenoid inside the valve body controls kick-down (passing gear). A switch on the throttle linkage (usually on the engine) is activated at wide open throttle to force a downshift for passing, etc. It will not kick down over a certain speed, usually in the 60-70 mph range. These are reasonably heavy duty transmissions. They are equivalent to a Ford-O-Matic or FMX three speed, which were used behind their 352 and 390 cid engines, moreover in smaller V8 Ford 150 thru 1979. Borg-Warner's website history page states they made Ford-O-Matic in 1950. Ford contracted to buy 50% of their automatic transmissions from Borg-Warner through 1958, and built a factory to build the other 50% on their own. That's why the same trans kit will work with Borg-Warner and several Ford auto transmissions; BUT it '''is not''' a Ford transmission! The Ford transmissions '''should''' bolt to the AMC bellhousing, no one I know has tried since the older Ford transmissions and parts availability is about the same as the Borg-Warner units. Kaiser Jeeps used a TH400 in the Wagoneer and pickup from 1963-'67. It's the "universal" TH400, which was the Buick Nailhead model. Buick Nailhead engines have a deep flange on the back of the block covering the flexplate/flywheel which require a shallower bellhousing than other GM engines. That shallow bellhousing left room to make an adapter without adding length to the engine/trans, so GM sold it as a "universal" model and continued production a few years after the Nailhead was discontinued. If you get one, make sure you get the 1-1/2" to 2" thick cast iron adapter as well as the flexplate and spacer. The crank will need a pilot bushing to match the flexplate. As stated, a Nailhead TH400 will work if you get just the adapter. Rolls-Royce and Jaguar used the universal TH400, among other smaller makers who didn't need enough units to warrant casting a new case. If using another AMC sourced transmission behind a former Jeep 327 with auto, make sure the thin pilot bushing is removed first. When Kaiser-Jeep became part of American Motors in 1970 (AMC/Jeep) the TH400 bellhousing was switched over to the AMC V8 and 72-06 inline six pattern. AMC phased in the use of the Chrysler Torqueflite for the 1972 model year (both AMC and Jeep vehicles used the Torqueflite with the exception of the Jeep Wagoneer which continued the use of the GM-sourced THM400 until 1979 when it was replaced by the Torqueflite 727 (later the 36RH).
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