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SHR MOD4 Valve Body

Weight:20.0 lbs
Installation Skill Rating:
Manufacturer:Southern Hot Rod
Southern Hot Rod
Base Price: $600.00
Price with Options: $600.00

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Southern HotRod MOD4 Valve Body:

Add this MOD4 Valve Body to your HEMI transmission for firmer and quicker shifts. This valve body was designed using Southern HotRod's Street testing that monitors all clutch pressures, torque converter pressures, and torque converter lock up clutch pressures all with accurate analog gauges. The more aggressively you drive, the firmer the shifts will engage, yet during normal driving the unit engages smoothly. Downshifts are also firmer than stock, increasing acceleration response.

Core Charge:

A $400 Refundable Core charge is required.

  • Designed by using a fully operational, test NAG1 that monitored all clutch pressures, torque converter pressures, and torque converter lock up clutch pressures all with accurate analog gauges.
  • The Mod4 modified valve body will increase the NAG1 shift pressures. The more aggressively the NAG1 is driven, the firmer the shift.
  • The downshifts are firmer than stock also, but not to the point of being too harsh.
  • Unheard of ......Full warranty for 1 year!

  • Dodge Challenger 5.7L & 6.1L LC 2008 to 2014
  • Chrysler 300 5.7L & 6.1L LX 2005 to 2014
  • Dodge Charger 5.7L & 6.1L LX 2006 to 2014
  • Dodge Magnum 5.7L & 6.1L LX 2005 to 2010
  • Jeep SRT8 6.1L 2006-2013

Mopar Vavle Body Install Guide
Dodge, Chrysler, or Jeep NAG1 Valve Body Removal:

1. Move selector lever to position park

2. Raise vehicle.

3. To disconnect 13-pin plug connector (1)

(a). Rotate the bayonet lock of the adapter plug (2) counter-clockwise.



4. Using a 7mm socket, loosen the adapter plug bolt (9) and remove from the adapter plug (10) from the transmission housing. The 2 Black O-rings should be on this adapter. Many times one of the O-rings will stick in the valve body. Remove it and install it back on the plastic adapter piece.

5. Detach oil pan (5).

6. Remove oil filter (4).


7. Unscrew 10 Torx socket bolts (3) and remove valve body.


Swap Top Electrical Connector Plate on NAG1 Valve Body:

8. Remove the 3 small bolts & retainers that hold the solenoids down. Note one bolt is shorter.

9. Remove solenoids...noting locations.

10. The solenoid at the bottom left (converter solenoid) sometimes needs a bit of wiggling to remove.


Unsnapping the electrical connector plate (dipstick side)

11. On the electrical connector side, push the plastic tab toward the long plastic dip stick guide. The plastic pin will pop right out of the steel plate.


Unsnapping the electrical connector plate (slide piston side):

12. Rotate the temperature sensor SLIGHTLY counterclockwise to release the tab from the steel plate.

If your electrical connector looks like this on the underside of the electrical connector plate, your NAG1 is in BAD shape. Valve_Body_Install_image5101

13. Reverse procedure to install the electrical plate.

14. It will simply clip into position.

15. Re-install the solenoids. Reference above photo for locations, actually they can not be installed in the incorrect position, they won't fit.

16. To install Use the same torque (71 in. lbs.) as all the other torx bolts.

HEMI NAG1 Valve Body Install:

1. Position the valve body in the transmission.

2. Insert selector valve (1) in driver of detent plate (2).

3. Reread #2

4. When installing the valve body in the transmission, the plastic part of the selector valve (1) must engage in the driver of the detent plate (2).
5. Install the Trox socket bolts (3) and torque to 71 in lbs (NOT FOOT LBS).

6. Install a new oil filter (4).

7. Install oil pan (5) and torque the pan bolts to 71 in lbs (NOT FOOT LBS).

8. Install the adapter plug (10) into the transmission housing and just SNUG the tiny bolt with a 7mm socket.

9. Check the two O-rings on plug connector (1). They must be BLACK or they will leak.

10. Replace O-rings and connector if necessary from the dealer.

11. Install the plug connector (8) into the adapter plug (10). Turn bayonet lock of adapter plug (10) clockwise to connect plug connector (8).

12. Fill the transmission with ATF+4. It will take approximately 4 quarts +/-.

13. Check the fluid level, it should be approximately 65mm up on a test dipstick (or anything that bottoms on the pan such as a very long clear zip tie) after about 1/2 hour or so of driving.

14. Enjoy the new feel of your HEMI transmission!

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