In 1998, due to durability concerns, the intermediate one-way roller clutch was replaced with a mechanical diode providing extra holding capacity and longer service. Advantages are that the shift points and firmness, as well as the lock-up point can be programmed. If a seam does exist, it will be necessary to inspect the oil pan to determine whether the transmission is a C3 or a C4. A smooth 1-2 shift at 12 mph tells you the governor and 1-2 shift valve are free; and that the servo is applying the band. Larger bellhousings accommodate a 12-inch converter; an 11-inch converter is found in the versions with the smaller bellhousing.
For 1967, the C4 went to a more conventional P-R-N-D-2-1 pattern and a different valve body. A lockup converter version called the C5. The C4 Dual-Range is equipped with a valve body that allows a driver to start out in second gear on snow and ice with a 2-3 upshift, which is the small dot off detent next to neutral on the indicator. Measure the length of the transmission's bell housing with a measuring tape to determine whether it is a C4 or a C5. Ford first introduced an automatic transmission in the Fifties discounting the Hydramatic offered in 1949-54 Lincoln Continentals , with the three-speed Ford-O-Matic, in service from 1951 to 1968.
Versions of the C4 have also been produced for big-blocks. This is when Ford engineers developed lightweight aluminum-case automatic transmissions for an exciting lineup of automobiles that arrived in the 1960s. Cores can be purchased and rebuilt to suit the needs of a specific vehicle for much less than a comparably rebuilt modern overdrive automatic transmission with electronic controls. The 3-speed C4 Cruise-O-Matic was introduced just in time for the 1964 model year. This is known as a split torque path. These are nothing that cannot be fixed however. You can tell you have a C4 because it has an aluminum case with detachable bellhousing.
As with everything, time and technology move on and today many overdrive automatics are available, mostly computer-controlled. While there is some speculation that the 70 can be multiplied by 10 to indicate the ft-lb of torque this transmission is capable of handling including torque converter multiplication, i. A smooth 1-2 shift at 12 mph tells you the governor and 1-2 shift valve are free; and that the servo is applying the band. Introduced in 1980, it was 's first four-speed automatic overdrive transmission. D, 2 and 1 Forward clutch All driving ranges Perform control pressure test R only Reverse and high clutch or low reverse band and servo Figure 72 Line control pressure testing is often called for on shift complaints; and may be useful in diagnosing slip conditions.
From 1971 to 1982, the C4 had a split-spline count. This causes the engine to flare up and then down again as the clutch cannot hold back the power of the engine. However, the advantages of the overdrive gear make up for this. For 1967, Ford did away with the Green Dot Dual-Range C4. The governor is still doing its job, the clutch circuit is hydraulically tight, and the 2-3 shift valve is free. This characteristic may result in a dark coloration of the fluid and does not by itself indicate malfunction or need for repair.
For 1971—1981, the C4 valve body changed significantly and does not interchange with 1964—1969 bodies due to changes in the case. These purely mechanical no electronic controls automatic transmissions are still popular with racers, hot rodders, and restorers today due to their simplicity and low cost. Upgraded and hardened input shafts, usually manufactured from chrome moly or billet are available. The C4 and C6 are held in higher esteem by automotive enthusiasts than the C3 and the C5 for their durability and simple designs. When you reach about 10 mph, governor pressure should cause a shift. Ford called its C4 the Cruise-O-Matic while Mercury called its C4 the Merc-O-Matic. Determine the number of bolts used by the transmission's oil pan.
Some C4s were built with a larger spread bell housing to use with V8s, but these are rare. The production plant in was converted to production of the which was relocated from , as the Livonia facility was converted to the. C4 teardown technique generally applies to the C6 as well, though there are some distinct differences in the ford c6 transmission and ford c4 transmission. In 1960, Ford introduced its lightweight-iron Falcon and Comet sixes. If they are not, a governor test can be performed either in the shop or on the road to determine if the governor is functioning. Remove torque converter and bench test for reactor one-way clutch slip. Now, governor pressure has risen high enough to overcome the 2-3 shift valve spring.
The fluid should be clean and normally not discolored. Internally, it has different valving and shift programming. For one model year only—1964—the C4 had a five-bolt bellhousing for V-8s only. This C4 Dual-Range is an early V-8 unit with a five-bolt bellhousing. At a glance, the Dual-Range valve body looks identical to 1967—1969. Again, depending on the application, three different length tailshaft housings are available; 7 inches for trucks, 14 inches for passenger cars, and 17. If they are not, a governor test can be performed either in the shop or on the road to determine if the governor is functioning.
The pan-fill C4 really is more about strength for heavy-duty applications like full-size cars and trucks than anything else because the bellhousing bolts to the case outside the pump housing. The one-piece casing with its integral bellhousing means each C6 is limited to the series of engines its bolt pattern will accept, and its sheer physical size and length means it is awkward to fit it in many cars. The 90-degree Fairlane small-block V-8s followed in 1962. Since control pressure opposing the governor is low, the 1-2 shift valve moves to charge the servo apply system. For the longest time, if you ran a Ford small-block or Windsor engine and wanted to run an automatic, your transmission of choice would likely be a C4.