By The Numbers
Let’s compare the gear ratios for each one of the particular transmissions found throughout the years behind light-duty diesel engines found in pickup trucks in the corresponding chart.
|
|
T-19
|
SM465
|
Getrag G360
|
NV4500 Dodge
|
NV4500 GM
|
NV5600
|
Mercedes G56
|
ZF 5
|
ZF6
|
|
Reverse
|
6.96
|
6.09
|
5.03
|
5.61, 5.04
|
6.34
|
5.63
|
6.29
|
5.24
|
5.23
|
|
1st
|
4.02
|
6.55
|
5.53
|
5.61
|
6.34
|
5.63
|
6.29
|
5.72
|
5.79
|
|
2nd
|
2.41
|
3.58
|
3.02
|
3.04
|
3.44
|
3.38
|
3.48
|
2.94
|
3.30
|
|
3rd
|
1.41
|
1.57
|
1.60
|
1.67
|
1.71
|
2.04
|
2.10
|
1.61
|
2.10
|
|
4th
|
1.0
|
1.0
|
1.0
|
1.0
|
1.0
|
1.39
|
1.38
|
1.0
|
1.31
|
|
5th
|
NA
|
NA
|
.77
|
.75
|
.73
|
1.0
|
1.0
|
.76
|
1.0
|
|
6th
|
NA
|
NA
|
NA
|
NA
|
NA
|
.73
|
.79
|
NA
|
.72
|
Several variations of the standard transmission have been made over the past two decades in the diesel pickup industry. Some have been very positive and some have not, but one thing is for certain, the manual transmission had a great part of the diesel industry until lately.
Technological advancements and part innovation has led to more automatic transmission advancements and what used to be a sore subject in the diesel industry, the automatic transmission, is now the only subject in terms of transmissions in pickup trucks with diesel engines aside from Chrysler. The next Tech column in the August issue of Diesel Tech will discuss the ins and outs of automatic transmissions and their rise from the dust over the years.
About The Author
Levi Perkins is the head instructor for the diesel program at the College of Southern Idaho located in Twin Falls, Idaho. The diesel program has had 100 percent placement in the last three years and provides future diesel mechanics and engineers a bright future in the diesel industry. For more information visit www.csi.edu or call 208-733-9554.