Turbo Hydramatic 700R-4 & Early 4L60-E Transmissions
Jeep New Process 208, 219, 228 & 229 Transfer Cases
Our TH700R-4 to Full-Size-Jeep / New Process Transfer cases conversion makes for a very strong, and capable assembly both on-road and off-road, and it remains one of our most requested automatic transmission to transfer case combinations.
The Novak TH700R-4 / 4L60 to Jeep transfer case adapter is 3.1" long for a combined transmission and adapter length of 26.7". The adapter itself is cast and machined of a high-grade aluminum alloy, featuring thick flanges, a heavy cross-section and strength adding gussets.
These kits are for the square, four-bolt tailhousing 700R-4 / 4L60 or 4L60-E, typically made through 1995. Some 1996 and later versions have a hex, six-bolt pattern tailhousing and removable bellhousing. See our Kit #4L63 if this describes your transmission.
We offer two adapter kits:
- Option I is for the 700R4 (aka, 4L60), which is the conventional, hydraulically controlled transmission. See kit #137-G, shown above, right.
- Option II is for the 4L60-E, which is the electronically controlled version of the 4L60. See kit #137-EG, shown below, right. This version permits you to use the electronically controlled 4L60-E (four-bolt version) with your transfer case. Note that you will need to mildly modify the 4L60-E tailhousing (instructions included) to install the included vehicle speed sensor (VSS). Also, make sure to plan on connecting your transmission to the GM ECM (if doing a GM engine swap) or get a standalone electronic transmission controller, available from GM, TCI, Jet, B&M and others.
Any version and year of the TH700R-4 can be adapted to these transfer cases including "90 degree" (Gen. I, II, III V6 & V8 Small Block or Big Block engines) and "60 degree (early S10 Blazer 2.8L engine style)" versions of the 700, as determined by your choice of engine.
Transmission Output Shaft
4wd versions of the Turbo 700R-4 / 4L60 and early 4L60-E are all ready to bolt up to our adapter assembly as the required style of output shaft is already installed. 2wd versions work equally well, but you will need to install a 4wd style transmission output shaft (image, below). We carry good, used GM shafts for this purpose. This requires disassembly of the transmission, and we recommend the services of a transmission professional. The basic installation is 2-3 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.
Transfer Case Input Shaft
The included input gear features 27 splines, to replace your Jeep 23 spline version. for a direct connection to the 4wd style transmission output shaft, as discussed above.
Transmission Rear Mount
This transfer case adapter's design is based on Novak's Universal Series adapters that feature a modular mounting and support system. Included with the adapter kit is a steel base that is a highly configurable mounting foot, and is ready to accept our industry standard urethane isolator mount, available for purchase (below). This is our preferred rear mount unit. Our #137 kits are 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 Shifter
This transmission conversion will allow for the retention of the factory shifters.
A broad variety of transmission shifters are compatible with this conversion, ranging from console shifters (i.e.; Art Carr, B&M, etc.), to direct-mount stick shifters (i.e.; Gennie, Lokar, etc.).
It is possible to use your FSJ's steering column-mounted shifter, but it lacks the one additional position needed for the 700R / 4L60. The throw distance is the same, but a new mylar P-R-N-O-D-2-1 and detent rack for your Jeeps GM steering column may be purchased from specialty companies.
Clocking Information & Driveshaft / Yoke to Pan Clearance
There are no driveshaft clearance issues with this conversion. If you are installing against a factory AMC engine with our #437-AMC adapter kit, your factory engine should already have this proper offset.
Driveshaft length changes are often required, as this geartrain combination is typically longer than factory Jeep combinations. However, some GM engine installations will allow for the transfer case to remain in its OEM location.
Some of our customers, fearful at the perceived expense of new or modified driveshafts, attempt to let the existing driveshafts dictate engine, transmission and transfer case location, sometimes to the detriment of the project. Driveshaft modifications are usually inexpensive when performed by driveline, RV or tractor implement specialists. New driveshafts are an option but seldom a requirement in regards to the actual successful conversion. Jeeps that require extensive travel or specialty-built driveshafts have this option available through several fabricators across the nation.
For every 10 degrees cooler you can keep the transmission, you can add 25,000 miles to its service life. Therefore, use of a transmission oil cooler is advisable for this automatic transmission. Use of a transmission temperature gauge is also a good idea. These are widely available and generally inexpensive.
With the increase in popularity of the newer, hotter burning, fuel-injected engines, it is increasingly wiser to run a stand-alone, dedicated transmission fluid cooler.
Engines & Engine Mounting
A 700R4 installation is typically done in conjunction with an engine conversion into the Jeep. These engines include the Chevrolet Small Block V6 & V8, from Generations I, II, & III, 1955-2006. Carbureted, TBI and TPI engines prior to 1993 will usually be paired with the classic, hydraulically shifted version of the 700R4.
|Novak's MM Series engine mounts, featuring excellent vibration dampening, superior strength and impressive adjustability - adjustable even after the engine is installed. The design and strength and affordability of our mounts are second to none.|
The electronic version of this transmission, the 4L60-E, will usually be done with a 1993-1997 powerplant and ideally sourced from the same GM vehicle for the sake of simplicity in wiring and computer programming, if any.
In any scenario, it is critical that the engine be installed (as the Jeep engines usually are) with an offset of 1" to 1-1/2" to the driver's side. Other engine mounts on the market - especially the bolt-in versions - do not take this into account and make other placement decisions for the installer that do not take the full powertrain into account. Novak offers what we have found to be the most intelligent engine mounting system for Jeeps available, allowing the installer to make an easy and satisfying decision as to powertrain placement with the 700R4 and the Dana 300 both considered.
|Advanced computer modeling methods were itegral to the design of our #137 adapter assembly. We were able to push the bounds of product and process well beyond the status quo.|
Use of factory axles is completely acceptable with this conversion. Axle upgrades are not necessary, but they may be chosen for reasons external to this transmission upgrade.