Depending on the size, both will have three or four planet pinion gears in the assembly. Along with application of the front clutch, fluid is directed to the low-reverse servo, which locks the low-reverse band tightly around the low-reverse drum-rear planet carrier assembly. Engine braking uses the low-reverse servo to apply the low-reverse band around the drum. The old unit could always be put back into service while the discrepancy was corrected. These changes have been incorporated on A-904s and 727s since 1966.
The output shaft has four sets of splines cut into it. Torqueflite Case Assembly Shown is a 727 case and associated pieces the 904 is almost identical except the size and shape of everything is slightly reduced. I am not going to describe each valve or spring just yet. There are many types of kits made to improve Torqueflite and I'll give my recommendations on the ones I'm familiar with. These kits, when used as directed, were helping to eliminate a lot of premature failure of severe service transmissions.
Review by Steve If you are thinking about rebuilding or upgrading the performance of your Chrysler A-904 or A-727 this is the book for you. However, if the transmission is removed, a few more key items can be changed to give bullet proof operation. The original 727 was basically unchanged through 1965. Many thanks to David Frey, Vicki Milley, Debbie Hoflo, and a very special thank you to Tom Mallot for his photographic help. It includes development, operation, repair and modification. It supports the low-reverse drum, the governor-output shaft assembly, and it directs oil to and from the rotating governor weights The governor works with the throttle pressure circuit to control shift points.
The tailshaft of the 727 Torqueflite adapts the rear of the transmission to the driveshaft, which powers the rear wheels. I had no idea that they would consider upgrading to a wider front clutch retainer bushing, so the end play was my primary suggestion. Lowering the pressure helped keep the seals from leaking or wear; a regulator valve added pressure when needed. The springs and valves work together to modulate fluid pressure to time application of the bands and clutches. Remember to keep your Chrysler service manual handy and follow whatever kit instructions you finally decide upon. Next is the case-to-tail shaft gasket and the governor support. Usually the higher performance transmissions use a 3.
This case is 727-A which fits all small blocks. The parking gear-governor assembly is splined to the output shaft so when the gear is stopped, the output shaft is stopped. The valve bodies are extremely well designed, and it is hard to make a mistake while assembling them. TorqueFlites are known for their dependability, but many have endured a tremendous amount of abuse over 50-plus years when hooked up to V-8 Mopar powerplants. I will present information that applies to both the 904 and the 727 Most front wheel drive vehicles are not used for heavy duty purposes or racing as of yet so not much has been written on them. In 1989 and 1991, integral overdrives were added, resulting in the A-500 based on the A-904 and the A-518 based on the A-727 ; the engine computer controlled an electric overdrive unit built into the extension housing. The shift lever is moved to get the car in motion and then left alone until the car is stopped.
Direct Drive While the transmission is in second gear, there is governor pressure on the 2-3 shift valve, the front clutch retainer is stopped by the kickdown band, and the rear clutch is applied, turning the front planetary and, therefore, the output shaft. Pressure forces the lip seals against their surfaces and pushes the piston away from the clutch hub and applies force to the clutch pack through the Belleville spring-pressure plate assembly. Because the A-500 and A-518 were essentially made by adding and an overdrive planetary gearset to the A-999, gear ratios were not optimal; they were not redesigned to match the torque curve and torque rise of the mated engine. Toss in the occasional Ford C4 and C6 transmissions and Tom was fortunate to have learned about and worked on the best. The 904 rear clutch is smaller but similar to the 727; and the front clutch hub-rear clutch retainer is in two separate pieces in the 727 but only one in the 904. Reverse Gear When the Torqueflite is shifted into reverse a couple of interesting things happen. As the input shaft turns 2.
Then the front clutch is applied, which locks on to the front clutch hub-input shaft assembly. Part three give some of the techniques that can be used to troubleshoot Torqueflite irregularities that I've seen most often. He recently retired as a Precision Cleaning and Contamination Control Process Engineer, Senior, for one of America's premier aerospace companies. The word firmer is relative; the shifts are not severe in most cases this depends on kit manufacturer as well as intended usage , they are just more noticeable. The rear clutch is still rotating the annulus gear and the sun gear is stopped so no torque is transmitted to the rear planetary. This ball-check valve lets that fluid that is under pressure from the clutch assembly spinning and throwing the fluid out due to centrifugal force out of the clutch cylinder or drum. The over-running Clutch is not shown and the Valve Body is actually a 1970 model.
There was not enough money to modify the gears; I was told that the 80th percentile average driver would not notice the difference. When the sun gear and the front annulus gear spin at the same speed the planet carrier has to rotate at that speed gear train rules dictate that when two members of the same gear rotate at the same speed, the whole gear set rotates at that speed. The amount of pictures and their quality is unbelievable. Row three displays the Rear Clutch assembly. This collection of technical automatic transmission manuals empowers every owner, mechanic, teacher and student. Tom Hand shares his decades of experience rebuilding TorqueFlite transmissions with chapters dedicated to troubleshooting, disassembly, reassembly, performance modifications, post-installation procedures, and the most thorough source guide ever offered in print. The four pinions will be found in higher performance units.
Fireball Performance Automatics in Williamsburg, Ontario has converted these to shift via cable linkage, allowing owners of older cars to update while keeping their. Below all this is the oil pan I've shown the Direct Connection deep pan with a drain plug , the fluid source for the hydraulic system some oil cooling is also done by the pan. Right below the band is the anchor that holds the band when the piston pushes the low-reverse lever, which is also held in place by the reverse lever shaft. The 904 has a smaller over0running clutch so it depends on the band to give it sufficient holding power to prevent breakage of the clutch. This is a good kit for motor homes, taxis, and police vehicles; good shifts, firm, yet comfortable B. The output shaft, plug, and thrust washer could be retrofitted back to the 1974 model year, as a group. When in Park, something has to lock the output shaft solid to prevent unwanted vehicle motion.