Shop Now for Dodge New Venture NV4500 standard transmission Mainshafts and Mainshaft Gears from our comprehensive, in-stock inventory of quality replacement parts for your 4x4 or 4x2 NV4500 5 speed.
1992-1993 Dodge D150, W150, D250, W250, Ramcharger with gas engine & NV4500
1989-1993 D250, W250, D350, W350 with Diesel Engine and NV4500HD Retro-Fit Conversion
Most NV4500 transmissions behind Diesel engines will need a Mainshaft sometime during the vehicle life-cycle due to wear in the 5th gear area. Mainshaft 5th Gear issues are mostly caused by the inability of stock and full-spline Mainshafts to adequately support the 5th Gear. Mainshaft Interchangeability: The NV4500 transmission is a marvelously adaptable transmission for use in any number of conversion scenarios. As far as the main case and reverse through 4th gearing, any 4500 Mainshaft can be swapped into any 4500 transmission. However, such a swap will also require one or more other changes which may include the Mainshaft 5th gear, Mainshaft Nut Set, Mainshaft Spacer or Vibration Damper, Speedometer Drive, and Tailshaft Housing.
Dan the Gear Man® Tech Note: Guys and Gals, we discuss the pros and cons of the full spline designs in my tech article: 5th Gear Failures and Solutions. The advantage of these shafts is they will get you back on the road for a reasonable amount of time and at a low cost. The disadvantage is no full spline shaft will prevent 5th gear loss because they do not address the cause of the problem. All full spline shafts of this type, made by anybody and sold by anybody are inherently weaker than stock and Torque King® shafts due to the groove machined in the shaft for the 3 piece thrust washer set.
Update: Torque King® Shafts are No Longer Available. Folks, the preceding Note was written in 2005. Everything still applies today, except we discontinued the Torque King® design a year or two after I retired in 2011. We never had a single Torque King® Shaft returned to us for a fifth gear nut failure, but despite the success of the product, the advancing age of NV4500 equipped trucks (most were built between 1994 and 1999) combined with the 6 figure price tag to renew the production contract caused the next generation management to discontinue the product. I was called back from full retirement to update the Tech Notes at the end of 2016 and updating this Tech Note was hard, but today, the only game in town for the Dodge NV4500HD is a full spline shaft.
