NP203.
NP208.
Transfer case genealogy began, as early as we can tell, in 1898 with Latil of France, who began making power packs that could replace the front axle, shaft, and horse of carts. In the ribbon of time spanning from four-wheel drives inception to today, transfer case technology has developed beyond any foreseeable stretch of the imagination. Large transfer case companies these days are designing chaindriven, shift-on-the-fly, magnesium cases that can withstand up to 7,890 lb-ft of torque like in the Ford Super Duty series.
The momentous last 20 years have been wrenched (OK, we mean drenched) with massive transfer caseage. This guide will help you sort through the mass and find that special transfer case that belongs to the year, make, and model for your buildup. Dont be afraid to recline on a spare tire, lie down in the grease puddles, and get the real dirt! Youll be at a junkyard after all, so enjoy the adventure. We did on our fieldtrip to our local Pick-Your-Part, and we definitely got down and dirty. What follows are the transfer cases you are most likely to find when you lie down under that 20 years of transfer case genealogy. Get ready to play a good ol game of I Spy.
73-79 Dodge, Ford, and GM trucks
What youll find: NP203
Type: Full-time four-wheel- drive, cast-iron, chaindriven case
Low range: 2:1
Why you want it: Its full-time and easy to find, and its housing is made from heavy-duty cast iron.
Why you dont: It weighs 170 pounds. The components may need to be replaced due to overuse. Over time, the full-time four-wheel drive could wear out other components.
'69-93 Dodge, 77-79 Ford, and 69-91 GM trucks
What youll find: NP205
Type: Part-time, cast-iron, geardriven case
Low range: 1.96:1
Why you want it: One of the burliest transfer cases ever built. Made with both right- and lefthand outputs, and divorced versions. It is heavy-duty, geardriven, and relatively easy to find. The 205 is available in six different versions.
Why you dont: The low range is an anorexic 1:96.1. The 205 may not be shift-on-the-fly for some, and confusion may exist because there are six versions. Additionally, some have a slip-yoke on the rear output.
80-93 Dodge, 80-86 Ford F-series and Bronco, 81-88 GM trucks, and 81-87 Jeep fullsize trucks
What youll find: NP208
Type: Part-time, aluminum, chaindriven case
Low range: 2.61:1
Why you want it: The 208 is lightweight, the chain- drive operates quieter, and it is shift-on-the-fly. Two additional perks are that the case is inexpensive and easy to find.
Why you dont: Weak slip-yoke design, aluminum housing may crack, removing the rear driveshaft causes an oil waterfall (Dodge and Jeep versions have bolt-on yokes), and several versions exist.
88-to-present Jeep Wranglers and Cherokees, 94-to-present Dodge ½-ton Ram pickups, 87-to-present Dakotas, 98-to-present Durangos, and 89-93 S-10 Blazers, pickups, and S-15 Jimmys and pickups
What youll find: NP231
Type: Part-time, aluminum, chaindriven case
Low range: 2.72:1
Why you want it: The upgrades and low-range gearsets available for the 231 are abundant. The case is lightweight and small and utilizes a fairly low low-range, and some have a true Neutral for flat towing. Additionally the slip-yoke rear shaft can be eliminated for improved driveline angles.
Why you dont: The transfer case was designed for the lightweight vehicle and generally cant handle big torque (or big tires). It has a weak aluminum housing, a rear slip-yoke, and a weak three-pinion planetary gearset.
88-2000 GM pickups, 89-2000 Blazers, Suburbans, and Jimmys, 88-93 Ramchargers and pickups, and 94-to-present Dodge ¾-, and 1-ton trucks.
What youll find: NP241
Type: Part-time, aluminum, chaindriven case
Low range: 2.72:1
Why you want it: Strong and available in a heavy-duty version in the Ram 2500 with the snowplow prep package
Why you dont: Watch carefully because two versions exist: an IFS version with the front output on the driver side and a solid axle version with the front output on the passenger side. The NP241 could use either a mechanical or electronic drive for your speedometer or vehicle speed sensor.
98-to-present Dodge Durango, Dakota, Hummers, 87-to-present Jeep Cherokees
What youll find: NP242 & NVG242
Type: Part-time/full-time, aluminum, chaindriven case
Low range: 2.72:1
Why you want it: Far better than the 231, the 242 allows you several options as far as routing power to your wheels. Slip-yoke eliminator kits are readily available. The Hummer uses a version of this case called the NVG242 HD AMG that has an external transfer case cooler.
Why you dont: You do. Keep it.
41-71 Jeep
What youll find: Dana/Spicer 18
Type: Part-time, cast-iron, geardriven case
Low range: 2.46:1
Why you want it: Its small, strong, lightweight, abundantly available, and relatively inexpensive, and you might even find one with a twin-stick shifter.
Why you dont: The Dana 18 gears constantly spin, thus they wear out sooner, and the output uses a weak 10-spline output shaft.
66-77 Ford Broncos, 72-79 Jeep CJs except Quadra-Tracs, 63-72 Jeep Gladiator pickups, 63-64 Jeep Cherokees and Wagoneers with manual transmissions, and 67-73 Jeepsters/Commandos
What youll find: Dana 20
Type: Part-time, cast-iron, geardriven case
Low range: 2.03:1 (for Jeeps), 2.46:1 (for Fords)
Why you want it: Both Jeep and early Bronco versions have a strong housing, are small and lightweight, and can handle a fair amount of torque. The Jeep version is available practically everywhere.
Why you dont: The Dana 20 for the Jeep contains poor low-range gearing and a low 10-spline output shaft. The Bronco versions may be difficult to find.
80-86 Jeep CJs and 80 Scout II
What youll find: Dana 300
Type: Part-time, cast-iron, geardriven case
Low range: 2.61:1
Why you want it: Of the Dana series of transfer cases the Dana 300 contains a lower low range than most, and the round-bolt pattern allows you to clock it for better driveshaft angles. Moreover, the helical-cut gears allow for quieter and easier operation and you can sneak a peek at them by removing the removable oil pan.
Why you dont: The Dana 300 needs to be internally modified to allow for flat towing. It has a weak output shaft, which can be upgraded, and an aluminum tailhousing.
Other Sightings
80-86 Ford F-Series and Broncos
What youll find: Borg-Warner 1345
Type: Part-time, aluminum, chaindriven case
Low range: 2.74:1
83-93 Ford Bronco II, Explorer, and Ranger
What youll find: Borg-Warner 1350
Type: Part-time, aluminum, chaindriven case
Low range: 2.48:1
87-93 Ford F-Series, and Broncos
What youll find: Borg-Warner 1356
Type: Part-time, magnesium, chaindriven case
Low range: 2.69:1
89-93 GM 1-ton dual rear-wheel trucks
What youll find: Borg-Warner 1370
Type: Part-time, aluminum, chaindriven case
Low range: 2.69:1
When Youre the Lucky One When Youre the Lucky One
While late-model stuff is out there (due to the unlucky drivers with their new vehicles) it is a little difficult to find these components at a junkyard. Perhaps your best bet is to hook up with someone who has the inside scoop on when totaled new 4x4s come into the yard if you do in fact want or need a later-model transfer case. Heres what you can put on your do-you-have-this-part list.
98-to-present GM ½- and ¾-ton pickups, Tahoes, Suburbans, Yukons, Denalis, and Escalades
What youll find: NVG246
Type: Autotrac part-time case that always spins the front driveshaft, aluminum, chaindriven
Low range: 2.72:1
99-to-present ¾- and 1-ton GM trucks
What youll find: NVG261
Type: Part-time, magnesium, chaindriven case
Low range: 2.72:1
01-to-present ¾- and 1-ton GM trucks
What youll find: NVG263
Type: Part-time, magnesium, electric shift, chaindriven case
Low range: 2.72:1
99-to-present Ford Super Duty and Excursion
What youll find: NVG271 (manual shifter) NVG273 (electronic shifter) Type: Part-time, magnesium, chaindriven case
Low range: 2.72:1
98-to-present GM ½- and ¾-ton pickups, Tahoes, Suburbans, Yukons, Denalis, and Escalades What youll find: NVG246 Type: Autotrac part-time case that always spins the front driveshaft, aluminum, chaindriven Low range: 2.72:1 99-to-present ¾- and 1-ton GM trucks What youll find: NVG261 Type: Part-time, magnesium, chaindriven case Low range: 2.72:1 01-to-present ¾- and 1-ton GM trucks What youll find: NVG263 Type: Part-time, magnesium, electric shift, chaindriven case Low range: 2.72:1 99-to-present Ford Super Duty and Excursion What youll find: NVG271 (manual shifter) NVG273 (electronic shifter) Type: Part-time, magnesium, chaindriven case Low range: 2.72:1