Shortens the shift throw on the NV5600 six-speed in 2000-2010 Dodge Ram 2500 and 3500 trucks, replacing the worn stock shifter linkage.
If your Cummins Ram 2500 or 3500 has the NV5600 six-speed and the stick wanders around the gate, buzzes at idle, or lets you miss the 3-4 shift because the throw is so long, the wear is usually in the shifter tower on top of the case, not in the gearbox. This short throw shifter kit replaces the factory tower linkage on the New Venture Gear NV5600 with a reworked iron lever and pivot that shortens the distance the stick travels between gears and firms up the feel. It supersedes the Mopar shifter tower kit 25683-KIT.
The NV5600 uses a direct-mount shifter. There is no cable or external linkage: the lever stub drops through a four-bolt tower on top of the transmission, pivots on bushings inside that tower, and its lower finger moves the shift rails in the top cover. Because the transmission is bolted to a Cummins, the tower does not sit directly on the case. A rubber isolator and spacer plate stack goes between them to keep engine vibration out of the cab. The stock replacement tower kit (25683-KIT) is listed by Allstate Gear as a tower, a spacer, four tower bushings and four bolts, and it interchanges with Mopar 05086622AA and 5012139AA. When the isolator softens and the bushings wear oval, the pivot point floats. That is what turns a firm truck shifter into a long, rubbery throw, and it is why replacing the tower assembly fixes the feel without opening the case.
Some problems will not be cured by a shifter. Grinding into a gear with the clutch pedal on the floor points to clutch release or worn synchros. A transmission that jumps out of gear under load points to internal wear. Both mean the case has to come apart.
With the engine off and the transmission in neutral, pull the boot and grab the lever right at the tower. If the stub rocks in its bore or the whole tower moves on the case, the bushings or isolator are done. Check that the four tower bolts are tight, then go through every gear with the engine off. If every gear goes in cleanly with the engine off but grinds with it running, look at the clutch hydraulics and release fork first. On 2001 and later trucks our Cummins clutch fork and pivot kit covers the release side. Our manual transmission repair cost guide explains why sorting this out first saves a teardown.
This kit is for the NV5600 six-speed in Dodge Ram 2500 and 3500 trucks. According to Diesel Hub, Dodge used the NV5600 behind the high-output 5.9L Cummins from the 1999 to the 2005 model year. The Mercedes G56 replaced it partway through 2005, and both transmissions were installed that year. The G56 has a different tower, so 2006 and later manual trucks need our G56 short throw shifter instead, and five-speed trucks need the NV4500 tower kit. On a 2005, check which gearbox you have: the NV5600 has a cast iron case, and the two units use different shift patterns. If your truck has been swapped or you are not sure, send us your year and VIN before ordering. You can browse other manual gearbox parts in our hard parts collection.
Nothing needs draining, but it is a good time to check the level at the fill plug. Diesel Hub lists 4.75 quarts (5 with the optional filter) of Mopar manual transmission fluid, part 4874464. Compare the threads on your shift stick with the new lever stub before you start, because NV5600 levers have been made with more than one 14mm thread pitch. A hand fluid pump makes topping off through the fill plug easier with the truck on the ground.
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Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
No. Dodge used the G56 six-speed from partway through 2005 onward, and the G56 uses a different shifter tower. 2006 and later manual Rams need a G56 shifter. This kit is for NV5600 trucks.
Both were installed during the 2005 model year. The NV5600 has a cast iron case and the G56 has an aluminum case, and the two use different shift patterns. If you are still unsure, send us your VIN and we will check before you order.
No. The tower comes off the top of the case from inside the cab and the fluid stays in. Check the level while you are there. Diesel Hub lists 4.75 quarts (5 with the optional filter) of Mopar manual transmission fluid.
Check before you install. NV5600 levers have been made with more than one 14mm thread pitch, so compare your stick with the new stub. If they do not match, you will need a matching stick or a thread adapter.
No. A shifter fixes slop, rattle and long throws. Grinding with the clutch fully depressed means the clutch is not releasing all the way or the synchros are worn. Check the clutch hydraulics and release fork before blaming the gearbox.
Shortening the throw changes the leverage, so expect a firmer, more direct feel and slightly more effort, especially when the gear oil is cold. That is normal for a short throw on a heavy-duty six-speed.
