New Venture 4500 Transmission Rebuild Manual
Manual transmission parts, rebuild kits and overhaul kits for the NV4500 - A complete line of transmission parts, rebuild and overhaul kits to help you with manual transmission problems NV4500. Installation Articles NV4500 Overdrive Transmission.
The NV4500 five-speed transmission in our high-mileage diesel-powered '95 Chevy 2500 pickup was exhibiting some bad behavior. Part of the problem was that the clutch wasn't releasing completely when the clutch pedal was depressed. This made selecting First Gear a grinding challenge.
Eventually, the main driver of this rig quit using the clutch during standard gearshifts because it wasn't disengaging anyway. Another problem was that as the transmission began to age, it began to leak. In a pinch, someone ignored the requirement of Castrol Syntorq LT synthetic oil (or equivalent) and fed it petroleum-based oil. Things quickly went from bad to worse as the synchronizer rings objected to the wrong oil. It wasn't long before the trans was becoming very hard to live with.
Since we're not manual-transmission rebuild experts, we took the truck to someone who is. Larry's Automotive is located on the outskirts of Rock City, Illinois.
The owner, Rick Jacobson, has been wrenching on trucks and cars since he was 12 years old, so he knows his stuff. His knowledge is vast and varied, and his resume includes a couple of years fabricating and wrenching for noted off-road racer Scott Taylor.
Jacobson and his team of technicians not only have a working knowledge of vehicles (including heavy trucks) from end to end, they also know the intricate workings of both automatic and manual transmissions. Best of all, Jacobson is a 'wheeler, so he's intimately familiar with how we use our rigs. Here's our Larry's Automotive-rebuilt trans ready to reinstall in our Chevy pickup. The folks at RSG note that one of the important things to remember about the NV4500 is that it requires Castrol Syntorq LT synthetic oil (or equivalent-RSG has an equivalent that they sell under their own brand name) due to the synchronizer material and design, as well as the large amount of gear teeth in mesh in this unit. Using standard gear oil will cause the NV4500 to shift poorly and eventually fail. The first place we called was Rockland Standard Gear. RSG, as they're called, has been in business for more than 25 years, and they're one of the largest suppliers of manual transmission and transfer-case parts in the country.
New Venture 4500 Transmission Parts
Here's some mind-boggling facts: They are the only aftermarket company ever selected to rebuild transmissions for ZF; they are one of five Master distributors for Borg-Warner transfer-case parts; they are one of 10 Elite distributors for Tremec; and they are a major distributor for New Venture Gear. Needless to say, we knew they could handle our NV4500 needs. Since the clutch in our Chevy was original, our second call was to Centerforce. The company has been around since the early '80s and was started by Bill Hays, the founder of Hays' Clutches in the 1950s. Bill Hays designed and patented the Centerforce Weighted Clutch System, which increases pressure-plate clamping force while maintaining easy pedal effort. Further, his new design solved the sticking-over-center problem of diaphragm clutches.
New Venture 1500 Manual Transmission
Centerforce offers a full range of clutches and flywheels for a number of applications. What follows is a synopsis of the major items addressed by the team at Larry's Automotive. It'll give you a good idea of what you can expect if you plan on having your NV4500 rebuilt. A busy shop and our tight deadlines meant we had to install the trans 'old-school' without the truck on a hoist. First, the clutch and bellhousing were installed, then the trans, and then the transfer case and driveshafts. Our first drive revealed a perfect shifting transmission, and thanks to the creativity of the guys at Larry's Automotive, we no longer have a dragging clutch.
Fifth Gear And The Dodge NV4500. Having problems with Fifth Gear in your Dodge NV4500? There is a fix. According to the folks at Rockland Standard Gear, the Dodge NV4500 had a design defect in the splines on the mainshaft Fifth Gear. The splines were not long enough and they were manufactured with an incorrect angle. This caused a slight creep of the Fifth Gear on the mainshaft due to throttle changes, which resulted in many of the units having the Fifth Gear loosen its retaining nut.
This allowed the gear to move out of position on the mainshaft and cease to function. If you have a Dodge NV4500 with this problem, you have options.
One is to purchase the kit that RSG offers. It includes a gear and mainshaft that utilize split-ring washers under a locknut to retain the gear under thrust loads. It also has redesigned full-length splines on the gear and corrected spline angles.