The Jeep 42RLE Automatic Transmission

The Jeep 42RLE  Automatic Transmission is commonly used in Jeep models, and it's also known as the Chrysler 42RLE, "Ultradrive", or early "A606". If you're wheeling a JK Wrangler, TJ Wrangler, or a Liberty, you are likely running one of these transmissions.

The Jeep 42RLE Automatic Transmission and the Jeep Liberty

While based on an older transmission design which was usually found in FWD cars and typically mounted sideways, it was modified around 2003 and began its career in RWD traditional applications. It featured bell housing and the casing was changed so that it could now be used behind an engine the long way. The initial reason for the new modification was so that it could be used in the Jeep Liberty. As with most electronic components of today, the transmission was given electronic upgrades, such as a TCM (Transmission Control Module), which allowed it to "learn a driver's driving habits." This was accomplished with an adaptive memory and a fully electronic shift control. If you want to use hard shifts, the torque converter uses an EMCC (Electronically Modulated Converter Clutch) to absorb some of that energy.

The 42RLE Engine In Other Jeep Models

The 42RLE transmission was not only used in the Jeep Liberty, it was also used in the Jeep JK Wranglers (2007 to 2013) and the TJ/TJL Wranglers (2003 to 2006). The transmissions are known to have some quirky problems now and then, and given how much they rely on electronics, that's not surprising. One important thing is that you must use the correct transmission fluid in a 42RLE transmission. Stay away from common brand ATF or Mercon/Dexrons. You normally have to use ATF+4 (check your owners manual!), which we carry in our factory MOPAR brand. Using the wrong fluid can damage the transmission and shorten it's life. Other common parts for the Jeep 42RLE automatic transmission are:

• Transmission Pan Filters
• Gear Shift Cables
• Neutral Safety Switch

The 42RLE is common, so if you have one, get to know it. We're happy to help you maintain it with fresh parts from  the XT. What type of transmission do you have in your Jeep? Has it been upgraded or have you kept it stock?