Jaime frees up the intermediate...
Jaime frees up the intermediate band and reverse/high clutch and forward clutch packages, which are the first items to come out through the front. Inside the reverse/high clutch are composition steel and friction clutches along with a clutch piston that engages them under pressure. For proper operation, good friction is needed.
Valve Body
If you're rebuilding a C4 to stock specifications, all your valve body should need is a thorough cleaning and inspection. Valve pistons should be checked for smooth operation-a nice, smooth glide back and forth with no resistance. Springs and check balls should be replaced as necessary. If you desire a firm shift, TCI Automotive has complete performance valve bodies and shift kits. Ask for the #522100 performance valve body.
| Application | Shift Improvement Kit |
| 1965-1966 | No. 526000 |
| 1967-1969 | No. 526100 |
| 1970-UP | No. 526200 |
When Should Your C4 Upshift?
|
| D1/Minimum Throttle with 3.00:1 or 3.25:1: | 1-2 | 8-10 mph |
| D1/Maximum Throttle with 3.00:1 or 3.25:1 | 1-2 | 31-41 mph |
| D1/Minimum Throttle with 2.80:1 or 2.79:1 | 1-2 | 9-11 mph |
| D1/Maximum Throttle with 2.80:1 or 2.79:1 | 1-2 | 36-44 mph |
| D1/Minimum Throttle with 3.00:1 or 3.25:1 | 2-3 | 12-24 mph |
| D1/Maximum Throttle with 3.00:1 or 3.25:1 | 2-3 | 54-71 mph |
| D1/Minimum Throttle with 2.80:1 or 2.79:1 | 2-3 | 14-25 mph |
| D1/Maximum Throttle with 2.80:1 or 2.79:1 | 2-3 | 64-76 mph |
These are the composition...
These are the composition clutches. Because this is a low mileage transmission, these "frictions" are in excellent condition but we're going to replace them with new frictions and steels.
After the reverse/high and...
After the reverse/high and forward clutches are removed, along with the forward and reverse planet carriers...
...the low/reverse drum and...
...the low/reverse drum and band in back are all that's left. Jaime grabs the C-clip, which frees up the tailshaft.
This is the parking pawl assembly,...
This is the parking pawl assembly, which goes to work when you place the shift selector in Park. Jaime removes the parking pawl gear and pawl, which strips the case clean. We're ready for parts cleaning and reconditioning.
National Parts Depot provided...
National Parts Depot provided us with a complete C4 transmission overhaul kit for '65-'69 Mustangs. Everything but the torque converter is here to perform a transmission rebuild: seals, servo pistons, clutch piston seals, the intermediate band only, clutches, filter, and other minor odds and ends. If you need hard parts like planet carriers, clutch drums and hubs, input and output shafts, TRC can get them for you.
Jaime stresses dressing all...
Jaime stresses dressing all contact surfaces for both a precision fit and less chance of leakage. Front pump mating surfaces are dressed with this stone.