Home --> Knowledge Search Novak Product Catalog Jeep Conversion Knowledge Base About Novak Contact Novak Cart

The Novak Guide to the
Jeep NVG 3550 Transmission

NV-3550 TransmissionThe New Venture Gear 3550 was released in the Jeep TJ Wrangler and XJ Cherokee in 2000, as the replacement to the AX15 transmission. It is also found in Dodge downsized pickups. It's last year in the Jeep was 2004, after which it was replaced by the NSG370 six-speed.

The 3550 is a takeoff from the New Process 3500 as found in smaller GM truck applications, though all external case features are different.

Features
The 3550 is a top-shifting, longitudinally-loaded transmission. It features five speeds with a direct drive fourth gear and an overdriven fifth gear. It is fully synchronized in all gears, excepting reverse, and has helically cut gears for all speeds.

Identification
The NV3550 is 16.7" long and has a cast aluminum case with generous ribbing. With its removable Jeep I6 bellhousing, it measures 23.1". The front bolt pattern is oval shaped and has dowel pins for precision centering alignment to the bellhousing. The front bearing retainer has an integral throwout sleeve for a conventional throwout bearing.

NVG-3550Spline count for the input shaft is 10 splines x 1-1/8" diameter. The output shaft has 23 splines and is flush with the rear face of the transfer case adapter flange.

NV3550 Specs at a Glance:

Make: New Venture Gear
Length: 16.7"
Height:
Weight: 97 lbs.
Case: Cast aluminum
PTO Port: None
Mfg. Torque Rating: 300 ft. lbs.
Gear Ratios (Jeep): (x-to-1):

4.01 2.33 1.39 1.00 .78 R3.57


Transmission Strength
The 3550 has a fairly generous torqe transmitting capacity (for a transmission of its size) as claimed by it manufacturer. Experience would suggest that it is about the same strength as the AX15, though a small number of failures have been reported to us by our customers. These were probably situations involving extreme terrain or improper use of the overdrive gear.

Popular transmissions to replace the 3550 for higher performance Jeeps include the SM420, SM465, T18 and NP435 four-speeds.

Transfer Case Compatability
The Jeep 3550 was factory married to the NP231 and NP241OR transfer cases. It features the common Jeep / Dodge 6-bolt transfer case mounting face for driver's side drop transfer cases. The 23 spline output shaft makes it compatible with the 23 spline version of the NP231.

Engine Compatibility and Adaptability
GM
Buick V6, Chevrolet Small Block V6 and V8 conversions to the 3550 are done with excellent success.

AMC Jeep
The 3550 is factory compatible with the Jeep / AMC 4.0L I6 engine. It can also be adapted to 1972-1991 AMC I6 & V8 engines following this procedure.

Sources
- New Venture Gear
- The Novak archives and its customer input
- Wikipedia
- DCx Jeep