The NP440 is a bit of an oddity in the fullsize pickup realm - it's a side-loading, four speed, overdrive transmission. First gear is relatively high (lacking a "granny" low), and fourth gear is a 0.73 to 1 overdrive ratio instead of the direct drive fourth gear typical of the period. The result was a gearbox that favored fuel efficiency but lacked the performance characteristics of transmissions such as the Muncie SM465, also available in 6.2 diesel applications. The NP440 is easily recognizable by its unique shift knob label, which reads "OD" in the traditional 4th gear position. Because of the transmission's 'uniqueness', it is somewhat rare.
While the Chrysler A-833 is well renowned for its strength, being used in applications including those powered by the legendary 426 Hemi and 440 Magnum big block V-8s, it's suggested that the NP440 features a maximum input torque capacity in the 270 lb-ft range. The NP440 features identical input and output splines to that of the Muncie SM465, characteristic of the fact that the transmissions were used in identical applications.
NP440, NP833 O.D. Transmission Ratios
1st |
2nd |
3rd |
4th |
R |
3.09 : 1 |
1.67 : 1 |
1.00 : 1 |
0.73 : 1 |
3.00 : 1 |
NP440, NP833 Transmission Specs
Transmission: |
New Process NP440 (NP833) |
Type: |
Side loading 4 speed overdrive manual transmission |
Manufacturer: |
New Process Gear |
Model Years/Applications: |
1981 - 1987 GMC, Chevrolet fullsize pickups (RPO code MY6) |
Synchronized: |
Synchronized in all forward gears |
Case Material: |
2WD cases were produced from cast iron or aluminum, 4WD cases were produced from cast iron only |
Case Length: |
10 5/8" |
Input Shaft Splines: |
10 spline |
Output Shaft Splines: |
27 spline |
Max Input Torque: |
260 lb-ft |
Trans Fluid Capacity: |
4.2 qts |
Trans Fluid Spec: |
Originally DEXRON II automatic transmission fluid, replaced by current ACDelco DEXRON VI spec |
Weight: |
~ 125 lbs (cast iron case) |
Shift Pattern: |
|
