Transmission Control Modules

Does the torque converter lockup fail to engage when it should, or does your automatic transmission shift sluggishly after adding more power? Transmission control modules and controllers let you adjust line pressure, lockup and signals so the transmission can work better with an engine that makes more power than stock.

What does a transmission controller do?

The parts here intervene in the way the automatic transmission is controlled. A lockup controller determines when the torque converter locks, while a line pressure controller can raise the pressure in the transmission so the clutches typically slip less at higher torque. In this category you will find, for example, CoPilot controllers from ATS Diesel for Dodge 47RE, 48RE, 68RFE and 545RFE as well as GM Allison 1000, a signal conditioner for the APPS/TPS signal and a TCM relocation kit for Duramax with Allison LCT1000. If the lockup itself also needs to hold more, the controller goes together with the right torque converters.

How to choose the right control module

• Transmission and model year: The part numbers are made for specific combinations, e.g. 2004-05 Dodge 48RE or 07.5-12 Dodge 68RFE.
• Connectors and wiring harness: Some are plug and play with a 24-pin connector, others come with their own wiring harness.
• Purpose: Choose based on the problem – lockup, line pressure or more complete transmission control.
• Transmission condition: More pressure won't fix worn clutches. Here, transmission rebuild kits can be the first step.

Installation and tuning

How much work installation requires depends on the product. Adjust in small steps and keep an eye on transmission fluid temperature, as harder loads can cause overheating. If you are considering a completely new unit, take a look at our automatic transmissions.

Frequently asked questions

What is the difference between a lockup controller and a line pressure controller?

A lockup controller controls when the torque converter locks and releases. A line pressure controller affects the hydraulic pressure in the transmission, which typically determines how firmly the clutches hold during shifts and under load.

Can a controller damage my transmission?

Incorrect settings can cause harsh shifts, increased wear or higher fluid temperature. It depends on the condition of the transmission and the settings, so adjust carefully and monitor the temperature, especially when towing or hauling heavy loads.

Is a transmission controller road legal?

It depends on the product and the vehicle. Check for the specific part number whether documentation or approval is available, and whether the modification must be registered, before using the car on public roads.