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From J. P. Callan who has installed the NV5600 in his 1998 12 Valve Ram.

Wed, 13 Oct 1999

      Here's some info on the 6-speed transmission for the Dodge Rams. Some changes are on the wind. I'm planning a swap-out of the NV4500HD in my 1998 2500 4x4 Quadcab for a 2000 1/2 NV5600 6-speed transmission. I don't know if you driven a new Dodge with the 6-speed, but let me tell you, it's sweet.
      The 1999 1/2 and 2000 0/2 NV5600 6-speed has a 1 1/4" input spline shaft. Starting in January or so, the revised NV5600 gets a 1 3/8" input spline shaft and a heavier clutch with a 1 3/8" bore. As a spare part, the 1999 1/2 and 2000 0/2 version of the transmission, part #52108402, costs about $6,000 and the 2000 1/2 version, part #52108502AA, will be slightly higher at about $6,300.
       The new transmission is 5 1/2" longer, so the rear drive shaft must be lengthened by 5 1/2" and the front drive shaft shortened by the same. While I could by 2000 vintage drive shafts as spare part, it's much cheaper to have a local driveline shop make the changes and rebalance the existing drive shafts. A new 5 1/2" longer shift linkage rod from the high/low/4WD range shift lever to the NV241HD transfer case is needed as is a different rear transmission mounting bracket. Otherwise, that's it for parts.
      I would be happy to provide interested Dodge owners with a complete bill-of-materials and step-by-step photos of my conversion after I finish.

Thu, 03 Feb 2000

       The 6-speed is installed in my 1998 12-valve 2500 Quad-cab 4x4 and fits like a glove! I used a 2001 NV-5600 instead of a 1999 or 2000 version.
       Chrylser and New Venture Gear beefed up the NV-5600 and the clutch for 2001 to better support up-rating the engine. Research at the Chrylser Proving Ground and using test trucks with uprated engines revealed that the transmission's input spline shaft sheared off (metal fatigue) after about 150,000 miles of towing their 20,000 lb.test trailer all around the western USA. So for 2001, the NV-5600 has a 1 3/8" input spline shaft instead the 1 1/4" shaft used in prior years. I had to replace my fly-wheel and clutch to accommodate the larger spline shaft. The new fly-wheel has an improved, larger pilot bearing, too. The clutch is 330 mm in diameter instead of the 300 mm version found in the 2000 and prior years. The new clutch can handle much more torque and is quite a bit bigger, using double the number of bolts to hold it to the fly-wheel.
      There were a few other critical (but inexpensive) parts needed to make it all work and work it does. The entire retrofit was accomplished using off-the-shelf Dodge and Cummins parts. No custom-built parts were needed. The only possible quibble to this is the drive shafts. Rather than buy new rear and front drive shafts (over $1,200), I had a local drive line shop cut 5 1/2" off the rear and replace the front drive line tube with a copy that was 5 1/2" longer. This method cost only $190 and they bead-blasted off the rust and painted the drive shafts gloss black. The reworked drive shafts look better that new ones.

J. P. Callan        Portland, Ore.

Sources:

• Enterprise Engine - complete transmissions and parts needed to install them
• South Bend Clutch - conversion clutch assy. so you can keep the original flywheel.

Last Update: February 4, 2000