New Process NP435 Manual Transmission

NP435 Transmission Specs, Ratios, ID Information

Though its most prominent application is 1969 to 1979 Ford pickups, the NP435 can be found in a variety of GMC, Chevrolet, and Dodge trucks. The most common NP435 transmissions feature a desirable 6.69 to 1 first gear ratio and relatively low 8.26 to 1 reverse ratio. It uses a standard "H" shift pattern, with reverse found to the right and down; it can be identified by its 8 bolt aluminum top cover and cast iron case.

The NP435 4 speed manual transmission was used in a variety of Ford, GM, Dodge, Jeep, and International Harvester trucks, although the most common application was in the Ford F-100/F-150/F-250/F-350 and other NP435 transmissions are relatively rare (thus this information will tend to focus on the Ford version). It is a heavy duty, top loading truck transmission known for its brute strength and ruggedness on the trail. Second through fourth gears are helical cut and fully synchronized, while first and reverse use spur cut gears and are non-synchronized. Dodge used the transmission selectively from 1966 to 1993, and GM from 1968 to 1972 (most GMC/Chevrolet pickup trucks received the company's Muncie 4 speed, not the New Process 435). Ford's most common application was 1969 to 1979 pickups, and this transmission had a favorable 6.69 : 1 first gear.

 

NP435 Transmission Gear Ratios

Model Designation

1

2

3

4

R

NP435E*

6.69 : 1

3.34 : 1

1.79 : 1

1.00 : 1

8.26 : 1

NP435A

4.56 : 1

2.28 : 1

1.31 : 1

1.00 : 1

5.64 : 1

NP435D

4.90 : 1

2.29 : 1

1.19 : 1

1.00 : 1

6.06 : 1

NP435L

4.90 : 1

2.29 : 1

1.19 : 1

1.00 : 1

6.06 : 1

*Most common model for Ford applications, desirable for deep 1st gear ratio

 

New Process NP435 Transmission Specs

Transmission:

New Process NP435 (various sub-models)

Type:

4 speed manual transmission

Applications:

• 1966 - 1992 Ford trucks (most common application)
• 1962 - 1993 Dodge trucks
• 1968 - 1972 GM pickups (limited, most GMC/Chevrolet pickups used the Muncie 4 speed)
• Various International Harvester and commercial vehicle applications

Case Material:

Cast iron w/ aluminum top cover

Case Length:

10-7/8"

Input Shaft:

1-1/16", 10 spline for Ford & GM applications, 23 spline in Dodge pickups

Output Shaft:

31 spline (4WD), 28 spline (2WD)

Weight:

~ 120 - 135 lbs

Fluid Type/Spec*:

Straight 50W or 80W-90 gear oil (non-hypoid recommended)

Identification

Top loading transmission, aluminum top cover, passenger side PTO port. Standard H pattern, reverse is to the passenger and down. The married 4WD version has a trapezoidal output flange, the divorced 4WD and all 2WD versions have a square output flange.


NP435 transmission identification

*Required fluid type and fluid capacity may vary with application and model year - refer to vehicle's owner manual.