The Extreme Short Shaft kit is what short wheelbase Wrangler owners have been dreaming of for decades. The Extreme kit not only improves on strength, but also increases driveshaft lengths by up to 7" over a stock application. It is over 3" shorter than a standard SYE kit, and 1-1/2" shorter than an ATLAS II. The Extreme SS kit comes with all necessary components to modify the stock 231 case. Speedometer readings are transferred through a tone ring and electronic sensor. To adjust the calibration a converter box is necessary to make any calibration adjustments.
Note: Requires a longer CV driveshaft, which is sold separateLearn More
SLIP YOKE ELIMINATORS - 101Most 231 transfer cases came from the factory with a slip-yoke rear output (see bottom photo). This slip yoke will slide or slip in and out of the rear of the transfer case as the suspension cycles up & down. When driveshaft angles are changed due to suspension height or suspension travel the slip yoke is forced to operate at an angle and can cause binding, and in some situations will crack the case.
Another problem with the slip yoke design is that the rear driveshaft yoke cannot be removed from the vehicle without loss of transfer case fluid.
Broken u-joints can often require the vehicle to be driven back off the trail with the front driveshaft only. Without eliminating the slip yoke on the
rear output, this would be impossible without losing the transfer case fluid, and causing transfer case damage.
On any short wheel base vehicle (such as the Wrangler), driveshaft angle is very critical and
must be addressed when making any suspension modifications. Standard factory Wrangler
driveshafts are about 12". This short driveshaft will cause severe vibration and premature u-joint failure if not upgraded.
A Short Shaft kit, or Slip Yoke Eliminator solves the short driveshaft length, allows driveshaft removal in the event of a u-joint failure without loss of fluid, and increases the output shaft strength dramatically allowing for increased
power and torque to be transferred to the wheels for traction.
There are several approaches to Slip Yoke Eliminator kits. Some use a "hack & tap" method which results in a lower priced kit, but does not effectively increase any strength, and can actually increase driveshaft vibration. TeraFlex was one of the innovators that developed a completely new heavy duty output shaft that can increase
torque loads by nearly 50%, as well as offer solutions to the original slip yoke problems. TeraFlex has perfected low range gearing and continues to lead the industry in quality performance transfer case products.
Top Photo: Extreme Short Shaft SYE
Middle Photo: Standard Short Shaft SYE
Bottom Photo: Stock Slip-Yoke
The Extreme Short Shaft kit does not use the traditional "speedometer gear" to
calibrate the speed of the vehicle. We have updated the signal to a digital reading
(similar to 03+ Rubicon). This allows a more accurate reading. The chart below
gives you the configuration of your vehicle by comparing tire size and axle ratio.
If your selection of tire size and gear ratio do not yield a result that is within the
green acceptable range a converter box will be necessary to make any calibration
adjustments.
An accurate speedometer reading is important both on and off road when detailing
travel routes and for on highway safety.
Factory speedometer variances are Ã?�Ã?±3% from actual speed. Recommended
speedometer driven gears are based on a manufacturer's published tire specs for
revolutions per mile. This may differ from manufacturer to manufacturer.
Extreme Short ShaftSpeedometer Calibration Chart
Installation Notes
Installation Difficulty:
Level 3 Advanced
Fits 231-J transfer cases only
Earlier 231 applications with mechanical speedometer cable require updating to an electronic speedometer.
Installation Time: 2-4 hours
Parts Included
Output Housing
Speed Sensor Ring
Bearing
Seal
Yoke & Nut
Installation Hardware
Specs
Fitment
Jeep Cherokee (XJ)
Jeep Wrangler (TJ)
Jeep Wrangler (YJ)
Jeep Wrangler Unlimited (LJ)
Description
Most 231 transfer cases came from the factory with a slip-yoke rear output (see bottom photo). This slip yoke will slide or slip in and out of the rear of the transfer case as the suspension cycles up & down. When driveshaft angles are changed due to suspension height or suspension travel the slip yoke is forced to operate at an angle and can cause binding, and in some situations will crack the case.
Another problem with the slip yoke design is that the rear driveshaft yoke cannot be removed from the vehicle without loss of transfer case fluid.
Broken u-joints can often require the vehicle to be driven back off the trail with the front driveshaft only. Without eliminating the slip yoke on the
rear output, this would be impossible without losing the transfer case fluid, and causing transfer case damage.
On any short wheel base vehicle (such as the Wrangler), driveshaft angle is very critical and
must be addressed when making any suspension modifications. Standard factory Wrangler
driveshafts are about 12". This short driveshaft will cause severe vibration and premature u-joint failure if not upgraded.
A Short Shaft kit, or Slip Yoke Eliminator solves the short driveshaft length, allows driveshaft removal in the event of a u-joint failure without loss of fluid, and increases the output shaft strength dramatically allowing for increased
power and torque to be transferred to the wheels for traction.
There are several approaches to Slip Yoke Eliminator kits. Some use a "hack & tap" method which results in a lower priced kit, but does not effectively increase any strength, and can actually increase driveshaft vibration. TeraFlex was one of the innovators that developed a completely new heavy duty output shaft that can increase
torque loads by nearly 50%, as well as offer solutions to the original slip yoke problems. TeraFlex has perfected low range gearing and continues to lead the industry in quality performance transfer case products.
Top Photo: Extreme Short Shaft SYE
Middle Photo: Standard Short Shaft SYE
Bottom Photo: Stock Slip-Yoke
The Extreme Short Shaft kit does not use the traditional "speedometer gear" to
calibrate the speed of the vehicle. We have updated the signal to a digital reading
(similar to 03+ Rubicon). This allows a more accurate reading. The chart below
gives you the configuration of your vehicle by comparing tire size and axle ratio.
If your selection of tire size and gear ratio do not yield a result that is within the
green acceptable range a converter box will be necessary to make any calibration
adjustments.
An accurate speedometer reading is important both on and off road when detailing
travel routes and for on highway safety.
Factory speedometer variances are Ã?�Ã?±3% from actual speed. Recommended
speedometer driven gears are based on a manufacturer's published tire specs for
revolutions per mile. This may differ from manufacturer to manufacturer.
Extreme Short ShaftSpeedometer Calibration Chart
Level 3 Advanced
Fits 231-J transfer cases only
Earlier 231 applications with mechanical speedometer cable require updating to an electronic speedometer.
Output Shaft
Output Housing
Speed Sensor Ring
Bearing
Seal
Yoke & Nut
Installation Hardware
Transfer Case Model: NP231
Shipping Weight: 15lb
Shipping Dimensions: 16in x 12in x 6in (L x W x H)
2001 Jeep Cherokee (XJ)
2000 Jeep Cherokee (XJ)
1999 Jeep Cherokee (XJ)
1998 Jeep Cherokee (XJ)
1997 Jeep Cherokee (XJ)
1996 Jeep Cherokee (XJ)
1995 Jeep Cherokee (XJ)
1994 Jeep Cherokee (XJ)
1993 Jeep Cherokee (XJ)
1992 Jeep Cherokee (XJ)
1991 Jeep Cherokee (XJ)
1990 Jeep Cherokee (XJ)
1989 Jeep Cherokee (XJ)
1988 Jeep Cherokee (XJ)
1987 Jeep Cherokee (XJ)
1986 Jeep Cherokee (XJ)
1985 Jeep Cherokee (XJ)
1984 Jeep Cherokee (XJ)
2006 Jeep Wrangler (TJ)
2005 Jeep Wrangler (TJ)
2004 Jeep Wrangler (TJ)
2003 Jeep Wrangler (TJ)
2002 Jeep Wrangler (TJ)
2001 Jeep Wrangler (TJ)
2000 Jeep Wrangler (TJ)
1999 Jeep Wrangler (TJ)
1998 Jeep Wrangler (TJ)
1997 Jeep Wrangler (TJ)
1995 Jeep Wrangler (YJ)
1994 Jeep Wrangler (YJ)
1993 Jeep Wrangler (YJ)
1992 Jeep Wrangler (YJ)
1991 Jeep Wrangler (YJ)
1990 Jeep Wrangler (YJ)
1989 Jeep Wrangler (YJ)
1988 Jeep Wrangler (YJ)
1987 Jeep Wrangler (YJ)
2006 Jeep Wrangler Unlimited (LJ)
2005 Jeep Wrangler Unlimited (LJ)
2004 Jeep Wrangler Unlimited (LJ)
The Extreme Short Shaft kit is what short wheelbase Wrangler owners have been dreaming of for decades. The Extreme kit not only improves on strength, but also increases driveshaft lengths by up to 7" over a stock application. It is over 3" shorter than a standard SYE kit, and 1-1/2" shorter than an ATLAS II. The Extreme SS kit comes with all necessary components to modify the stock 231 case. Speedometer readings are transferred through a tone ring and electronic sensor. To adjust the calibration a converter box is necessary to make any calibration adjustments.
Note: Requires a longer CV driveshaft, which is sold separateLearn More
SLIP YOKE ELIMINATORS - 101Most 231 transfer cases came from the factory with a slip-yoke rear output (see bottom photo). This slip yoke will slide or slip in and out of the rear of the transfer case as the suspension cycles up & down. When driveshaft angles are changed due to suspension height or suspension travel the slip yoke is forced to operate at an angle and can cause binding, and in some situations will crack the case.
Another problem with the slip yoke design is that the rear driveshaft yoke cannot be removed from the vehicle without loss of transfer case fluid.
Broken u-joints can often require the vehicle to be driven back off the trail with the front driveshaft only. Without eliminating the slip yoke on the
rear output, this would be impossible without losing the transfer case fluid, and causing transfer case damage.
On any short wheel base vehicle (such as the Wrangler), driveshaft angle is very critical and
must be addressed when making any suspension modifications. Standard factory Wrangler
driveshafts are about 12". This short driveshaft will cause severe vibration and premature u-joint failure if not upgraded.
A Short Shaft kit, or Slip Yoke Eliminator solves the short driveshaft length, allows driveshaft removal in the event of a u-joint failure without loss of fluid, and increases the output shaft strength dramatically allowing for increased
power and torque to be transferred to the wheels for traction.
There are several approaches to Slip Yoke Eliminator kits. Some use a "hack & tap" method which results in a lower priced kit, but does not effectively increase any strength, and can actually increase driveshaft vibration. TeraFlex was one of the innovators that developed a completely new heavy duty output shaft that can increase
torque loads by nearly 50%, as well as offer solutions to the original slip yoke problems. TeraFlex has perfected low range gearing and continues to lead the industry in quality performance transfer case products.
Top Photo: Extreme Short Shaft SYE
Middle Photo: Standard Short Shaft SYE
Bottom Photo: Stock Slip-Yoke
The Extreme Short Shaft kit does not use the traditional "speedometer gear" to
calibrate the speed of the vehicle. We have updated the signal to a digital reading
(similar to 03+ Rubicon). This allows a more accurate reading. The chart below
gives you the configuration of your vehicle by comparing tire size and axle ratio.
If your selection of tire size and gear ratio do not yield a result that is within the
green acceptable range a converter box will be necessary to make any calibration
adjustments.
An accurate speedometer reading is important both on and off road when detailing
travel routes and for on highway safety.
Factory speedometer variances are Ã?�Ã?±3% from actual speed. Recommended
speedometer driven gears are based on a manufacturer's published tire specs for
revolutions per mile. This may differ from manufacturer to manufacturer.
Extreme Short ShaftSpeedometer Calibration Chart
Installation Notes
Installation Difficulty:
Level 3 Advanced
Fits 231-J transfer cases only
Earlier 231 applications with mechanical speedometer cable require updating to an electronic speedometer.
Installation Time: 2-4 hours
Parts Included
Output Housing
Speed Sensor Ring
Bearing
Seal
Yoke & Nut
Installation Hardware
Specs
Fitment
Jeep Cherokee (XJ)
Jeep Wrangler (TJ)
Jeep Wrangler (YJ)
Jeep Wrangler Unlimited (LJ)
Reviews
