Of course, I’m trying to take it easy for the first few hundred miles on this transmission, and I’m not quiet past that point yet, but when I get some real miles on this tranny, you’ll see a long-term update on how it has been holding up.
| Gearstar TH400 |
Level 2 |
Level 3 |
Level 4 |
| Max Power |
450 hp, 425 lb-ft torque |
550 hp, 475 lb-ft torque |
850 hp, 650 lb-ft torque |
| Matched Torque Converter |
12” or 13” heavy-duty high-performance furnace-brazed, 1,600-2,200 rpm stall |
10” heavy-duty furnace-brazed flanged hub with billet cover, 2,600-3,000 rpm stall |
10” or 11” six-bolt heavy-duty furnace-brazed flanged hub with billet cover, 2,600-4,500 rpm stall |
| Shift Kit |
Transgo shift kit |
Transgo reprogramming shift kit with Shift Command |
Transgo reprogramming shift kit with Shift Command or full-manual forward pattern OR Gearstar full-race shift kit |
| Bands and Internals |
Master overhaul kit with high-energy frictions and all new steel plates High-flow filter New kickdown solenoid Adjustable modulator New front band New Borg-Warner low-reverse band New Torrington bearings Bushing kit with flanged no-walk-out case bushing Thrust washer kit |
Master overhaul kit with Raybestos Stage 1 racing frictions and hardened Kolene steel plates High-flow brass filter New kickdown solenoid Adjustable modulator New front band New Borg-Warner low-reverse band with heavy-duty lugs New Torrington bearings Bushing kit with flanged no-walk-out case bushing Thrust washer kit |
Master overhaul kit with Raybestos Generation II racing frictions and hardened Kolene steel plates High-flow brass filter New kickdown solenoid Adjustable modulator New Kevlar front band New Borg-Warner low-reverse band with heavy-duty lugs New Torrington bearings Bushing kit with flanged no-walk-out case bushing Thrust washer kit |
| Clutches, Drums, Sprags, Springs, Rollers |
High-capacity direct clutch drum Heavy-duty forward clutch hub New low-reverse Spring & Roller |
High-capacity direct 8-clutch drum with 34-element intermediate sprag and hardened race Heavy-duty forward steel clutch hub Extra-capacity intermediate clutch assembly New low-reverse spring & roller |
High-capacity direct 9-clutch drum with 34-element intermediate sprag and hardened race Extra-capacity intermediate clutch assembly 300M billet forward clutch hub Reinforced forward drum assembly New low-reverse spring & roller High-rev spring kit |
| Fluid Pump |
High-volume high-flow pump assembly with new gears |
High-volume high-flow pump assembly with new gears |
High-volume high-flow pump assembly with new hardened gears |
| Shafts |
Stock shafts (optional shafts available) |
Stock shafts (optional shafts available) |
300M main shaft 300M hardened input shaft |
| Transmission Pan |
Chrome pan with drain plug |
Extra-capacity cast aluminum pan with drain plug |
Extra-capacity cast aluminum pan with drain plug |