Dodge Ram 2002-2008: Transmission Options

Can you get a new transmission hauled into your 3rd generation Dodge Ram? The answer is a simply "yes," but which one to choose is a little more complex.

By Mark Garrett - July 30, 2015
Contributors: Precision Transmission Group, Midwest Transmission

This article applies to the 3rd Generation Dodge Ram (2002-2008).

Dodge offered eight different transmission models in their Ram trucks. Which transmission was installed depended on which engine the truck has. Five of the transmissions are automatic and three are manual. The automatic transmission comes with 4, 5, or 6-speed gears, while the manual transmissions has only 5 or 6-speed gears. Dodge did a good job of matching the transmission to the engine and the gross vehicle weight of the truck. Let's take a look at which transmission came with which engine.

Automatic Transmissions

42RLE 4-Speed Automatic Transmission

The 43RLE is a fully electronically-controlled automatic transmission. With its adaptive memory, the truck's transmission control module (TCM) learns the operator's driving habits and controls only the rear wheels. It is matched to the 3.7L V6 gasoline engine. The gear ratios are:

1st: 2.80
2nd: 1.55
3rd: 1.00
4th: 0.69 (overdrive)

45RFE 4-Speed Automatic Transmission

The 45RFE is a fully electronically-controlled automatic transmission manufactured in Kokomo, Indiana. It is sometimes matched to the 3.7L V6, but is normally matched to the 4.7L V8 gasoline engine. The gear ratios are:

1st: 3.00
2nd: 1.50
3rd: 1.00
4th: 0.75 (overdrive)

545RFE 5-Speed Automatic Transmission

The 545RFE is a fully electronically-controlled automatic transmission manufactured in Kokomo, Indiana. It is matched to the 3.7L V6, the 4.7L V8, and the 5.7L V8 gasoline engines. The gear ratios are:

1st: 3.00
2nd: 1.67
3rd: 1.00
4th: 0.75
5th: 0.67 (with 4th and 5th being overdrive)

Figure 3. 545RFE automatic transmission.

68RFE 6-Speed Automatic Transmission

The 68RFE is a fully electronically-controlled automatic transmission. It is beefed up internally to handle the diesel engine and is matched to the Ram 2500 and 3500 with the 6.7L Cummins turbo-diesel engine. The gear ratios are:

1st: 3.23
2nd: 1.83
3rd: 1.41
4th: 1.00
5th: 0.81
6th: 0.62 (with 5th and 6th being overdrive)

AS68RC 6-Speed Automatic Transmission

The AS68RC is manufactured by AISIN Duty Automatic. It is beefed up internally with wide ratio gearing for better acceleration and higher fuel economy from the diesel engine. It offers advanced electro-hydraulic clutch-to-clutch shifting for excellent shift quality and is PTO-capable as well. This transmission is matched to the Ram 4500 with the 6.7L Cummins turbo-diesel engine.

Figure 5. AS68RC automatic transmission.

Dodge Ram 2002-2008: Transmission Options