Allison Transmission in a Dodge
During the last 19 years of being in the torque converter business I have had the opportunity to serve customer's request for custom torque converters. After sitting and listening to their needs I have found out there is a quest for the ultimate durable power train.
Since 1989 Dodge has offered a diesel engine option from Cummins, It is known as the Cummins B series. This 5.9 liter unit was a direct-injected, turbocharged, six-cylinder inline engine. The B series was originally developed for agriculture and commercial trucking, and had a maximum gross vehicle weight rating of 33 tons. In its early fitting into a Ram truck, The "B" motor was significantly derated. With time and alterations the "B"'s horsepower was increased.
Another great feature of the "B" motor, when properly maintained it has an incredible long life. Many of those trucks are used heavily some never seen a kind mile. The owners of those trucks consider the "B" the best engine ever sold in a pickup truck. Along with its reliability, its inline design makes it easy to service and easier to modify for power increases.
Shops that have worked in the transmission industry noticed the stock transmission design has not always been able to handle the power of this engine. From the 727 torqueflite to electronic driven 48re, All of these Chrysler designs take their roots from the early 60's. Chrysler has tried to do upgrades to this style of transmission matching the increased horse power output of the engine. Most truck owners have been lured into purchasing performance engine upgrades. These engine modifications can easily offsetting any of Chrysler's attempts in improving transmission durability. There has also been a great aftermarket created offering up vastly improved parts both in transmissions and torque converters. These company's make large claims touting their parts are near unbreakable.
What a few customers have told me is that there is a much more durable transmission made by Allison know as the 1000, 2000, and 2400. In the quest for a more durable power train some have wished to put an Allison 1000 in their Dodge truck. I have spent many hours listening to those requests. One day I decided to put an Allison 1000 transmission in my own Dodge truck. I set out to design all the adaptors and modify the torque converter. A few things I wanted was an installation that looked like it came from the factory ,no body lift, no floor board cutting and re-welding, no starter repositioning. I even wanted to reuse the stock shifter. Another thing on the wish list was being able to read and trouble shoots any transmission codes by using the Allison DOC program. After accomplishing all of this, I now have installed in my truck gen 4, 6 speed capable Allison 1000 transmissions.
The test drive and the daily drive.
Many people have come to know Allison transmissions for durability. After the test drive and the weeks of daily driving, I have discovered there is a much more valuable side to the Allison transmission. During weeks of daily driving, some of the positive features I found out are reverse. Reverse gear is a gear that is not given much thought unless it doesn't work. With the reduction in reverse at nearly 4.49:1 backing in heavy trailers uphill is a near effortless task now. Not much more than the idle of the engine are needed. The forward gears are well thought out in their spacing. Having a 3.10:1 first, 1.81:1 second, 1.41:1, third, 1.00:1, fourth, 0.71:1 fifth, and 0.61:1 sixth. Allowing the engine to move weight fast with good gearing for highway speeds, the off-the-line acceleration for such a heavy and large truck is near eye-opening. Another unknown fact is how the torque converter stall would work. When building my own torque converter, there are 4 stall selections or known as Stall torque ratios, 2.05:1, 2.00:1, 1.73:1 and 1.58:1. I choose the lowest stall combination 1.58:1. During the truck's life I ran a modified Chrysler torque converter that I personally built with a reduction in stall. My thought was to bring stall and lock up closer. Nerveless all this work didn't seem to mater, when the truck's torque converter wasn't in lock up it felt like I was going nowhere. The Allison converter doesn't feel like that. With its much larger turbine and impeller reaction areas, the Allison converter has a much more progressive feel. To sum it all up truck owners want durability, what I found, is better drivability.