DAP now has an improved version with shot peened springs and no dead wire ends. These heavier springs replace the stock governor springs to safely allow the engine to reach higher RPMs, up to 4000rpm, so there is no momentum loss when shifting gears while towing up a hill, brutal to shift so early with the nv4500. DAP's governor spring kits are complete with all necessary parts 2 (6 springs and pedestals) To limit the pump to 3000rpm simply omit one of the springs per instructions. They are perfect for those who tow heavy loads and want more responsive power. 60# valve springs required for over 3200RPM
Diesel Auto Power
DAP Premium 3K And 4K Governor Spring Kit - 12VGS3K4K
5/5 Stars out of 1 Reviews
Easy to install, probably a hour and a half after adjusting idle. I've owned this truck a long time(97 3500 W/NV4500) and I should have done this long ago. These springs made a big difference between 3/4th and 4/5th gear, but you will notice the full fueling all over.