G2 Axle and Gear NP231 Slip Yoke Eliminator Kit - G/237-231SYE

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  • G2 Axle and Gear | Part Number: G/237-231SYE
  • Fitment:Universal Fit
  • Includes New Tail Shaft:Includes New Output Shaft
  • Replacement Yoke Type:1310 CV Style Yoke
  • Includes New Extension Housing:Includes New Extension Housing
  • Availability:In Stock
  • QuantityGT3:true
  • Transfer Case Model:NP231


This heavy duty slip yoke eliminator kit converts the standard slip yoke of a Jeep NP231 transfer case to a more reliable fixed yoke output accommodating a longer drive shaft. Drive shaft sold separately.

Customer Reviews

4.7 4.7
6 Customer ratings

Customer Images

5.0 Great deal

Great parts. I like how the case already has the seal and the bearing installed. Have not installed yet, but should go smoothly.

from Colorado |
4.0 Nice quality, careful with bolt sizes

Very good kit, has everything your need and goes together easily... however the Speedo gear hold down screw is threaded for an M8-1.00, but the OEM housing is threaded for 5/16-18. The housing is aluminum, so it could be very easy to cross thread that bolt if you don’t immediately realize it’s not the right size. 5-16 & M8 are very close in size.

from Prosper, TX |
New tail housing & yoke
4.0 Complete Kit - Fit well

This kit arrived quickly and was complete. It has all of the hardware necessary for a complete install. Black silicone gasket material (RTV) is recommended and Blue LockTite. The RTV and LockTite are not included, so you'll have to have some on hand. We removed our transfer case from the vehicle, which made the install fairly easy. (watch a YouTube video for helpful tips on separating the case). The kit fit the NP231D transfer case perfectly. We haven't run it yet, just ordered our new drive shafts, which you may need for your project as the T-case output shaft is shorter than the stock configuration.

from Central California |


Question & Answers

6 Answered questions

Q: Is the SYE housing a separate sealed unit from the rest of the transfer case? Noticed they have a fill plug. Answer this question

A: It is a separate housing and the hole that you see is where the speed sensor goes for your speedometer.

Answered by Charles01TJ from Florida on 12/19/2021

A: The SYE housing is not sealed off from the rest of the transfer case.  There is no fill plug on it, but there is an opening for the speedometer drive gear, and also an opening/plug for the selector shaft.    

Answered by Craig N from Prosper, TX on 12/15/2021

Q: Will this fit a np231d (2000 Ram 1500)? the fitment guide says it will fit and I’ve been told that the J and D cases are similar but wasn’t sure. Answer this question

A: Depending which version of the NP231D you have; the output shaft maybe different than the J so I really cannot confirm if this kit will fit your D due to the differences.  The other differences are the number of planetary gears, chain and sprocket width and lack of a true neutral in some cases. 

Answered by Charles01TJ from Florida on 04/03/2022

Q: Will this work with the np 231c Answer this question

A: The G/237-231SYE will not fit the NP231C rear case half. I have been told that by using the rear case half of a NP231J on the NP231C that it can be done.

Answered by Kelly from 4WP Corporate Headquarters on 02/16/2021

Q: Do you sell a similar kit for the 2002 s 10 zr2 i think its NP233c or 231HD Answer this question

A: No we do not at this time.

Answered by Kelly from 4WP Corporate Headquarters on 02/16/2021

Q: Will this fit on 2002 chev s10 zr2 v6 4.3 l Answer this question

A: No, this fits NP231/231J transfer cases only.

Answered by Mario from Compton, CA on 02/12/2021


G2 Axle & Gear uses the strongest and latest generation materials to manufacture products capable of handling heavy loads. When it comes to axle assemblies, core lockers, driveshafts and sway bars, G2 is the first name in durability and reliability. Off-roading can heap punishment on a Jeep and G2's laser-cut components offer superior handling on challenging terrain and on-road drives. Parts are easy to install and easy to service and above all, they remain operational in adverse environments. Shop G2 Axle and Gear Now


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