Product Description
Adapting the
GM 4L60-E (later version) Transmission
to the
Jeep Models 207, 231, 242, 249 & 241OR Transfer Cases
Our 4L60-E (including the 4L65 & 4L70) to the Jeep New Process (or New Venture) transfer cases conversion makes for the most refined assembly both on-road and off-road, and has become one of our most popular transmission to transfer case combinations.
The adapter kit is designed for compatibility with the Jeep NP207, NP231, NP242, NP249 & NP241OR "RockTrac"transfer cases.
The Adapter
The 4L60-E to Jeep NP / NVG transfer cases adapter is very compact at only 3.0" long for a combined transmission and adapter length of 24.5" (equivalent to a 17.5" manual transmission). The adapter itself is machined of a 6061 billet aluminum alloy, featuring thick flanges and a heavy cross-section.
4L60-E Versions
Any versions (2wd or 4wd) and year of the HydraMatic transmission can be adapted to these transfer cases. There are no inherent advantages to the 2wd vs. 4wd transmission.
Transmission Output Shaft Replacement
This #4L61 kit comes with a new output shaft to be installed in your 4L60E transmission that was originally a 2wd or 4wd version - either works equally well. The output shaft is of a premium alloy steel, precision splined and specially hardened for strength and against wear, providing a superior interchange. This shaft connects the transmission output directly into the existing 23 spline NP / NVG input gear for the strongest connection. Transfer case disassembly is not typically required.
Installation requires disassembly of the transmission for which we recommend the services of a transmission professional, though good work is within reach of the home mechanic. The basic installation is 3-4 hour bench job and may include simple gasket and seal replacements. Some choose this as the time for a more thorough master rebuild and update if necessary.
Vehicle Speed Sensor
The adapter assembly integrates the Vehicle Speed Sensor (VSS) necessary for the operation of the 4L60-E's computer. This greatly simplifies the installation process and eliminates the need for a transfer case range switch circuit and logic, making all GM 2wd and 4wd engines, transmissions and their PCM's great candidates for the installer.
Transmission Rear Mount
This transfer case adapter's design is ready to accept our industry standard urethane isolator mount, available for purchase. This is our preferred rear mount unit. Our kit is designed for it, and its usage is essential to protect powertrain components from the flex and jar typical of any automobile, but especially Jeeps.
Whether you are assembling onto a stock cross member / skidpan or if you are setting up a high-clearance skid plate, you will find it to be a clean and simple process.
Transfer Case Clocking
Our adapter is clocked optimally for slightly better ground clearance than factory locations, which is actually quite good.
** You will need a Transmission Mount listed below to mount this adapter to a crossmember **