Jeep uses a variety of four-wheel drive systems on their vehicles. These range from basic part-time systems that require the driver to move a control lever to send power to four wheels, to permanent four-wheel systems that monitor and sense traction needs at all four wheels automatically under all conditions.

Summary +Jeep four-wheel-drive system branding Feature Command-Trac Rock-Trac Selec-Trac Quadra-Trac Quadra-Trac II Quadra-Drive Quadra-Drive II Freedom Drive Active Drive Selec-Terrain Years 1980–present 2003–present 1983–present 1973–1998 1999–20042005–2021 2007–2017 2014–present 2011–present Full/Part-time 4WD Part Part Part/Full Part/Full Full/AdaptiveFull/Adaptive Full Full Full Modes 2Hi, 4HI PT, 4LO PT 2Hi, 4HI PT, 4LO PT 2WD, 4WD HI PT, 4WD HI FT, N, 4WD LOST II: 2WD, 4WD Auto, N, 4WD LO 4WD HI Locked (PT), 4WD HI Open (FT), N, 4WD LO Open (FT), 4WD LO Locked (PT) QTII: 4-All Time, N, 4-LoQTI: 4-All Time 4-All Time, N, 4-Lo4-All Time, N, 4-Lo — ADII: 4-LowADL: 4-Low, Rock Auto, Snow, Sport, Sand/Mud, Rock Transfer case NP208 (1980–87)NP231/207 (1984–2001)NP241J (2002–07) NV241OR (2003–present) NP228/229 (1983–91)NP242 (1987–2007)MP3022 (Selec-Trac II, 2008–12 & 2018–present) BW1339 (1973–79)NP219 (1980–82)NP/NV249 (1993–98) NV247 (1999–2004)NV245 (2005–10; WK) MP3023 (2011-2021; WK2) (electronic) — — Differential F Tru-Lok Vari-LokElectronic LSD (WK) /No LSD - Traction Control Only (WK2/WL) Open C — — Open or locked Limited-slip / locking Limited-slip / lockingElectronic clutch pack Electronic R Trac-loc LSD Tru-Lok Trac-loc LSD Vari-LokElectronic LSD Open Low Range 2.72:1 4:1 2.72:1 2.57:1 QTII: 2.72:1 2.72:1 — — —

Notes

Command-Trac

Command-Trac Command-Trac was first introduced using the NP208 transfer case in the full-size Jeeps (SJ series) in 1980. The drive modes are the same as with the Dana 18 and 20 transfer cases: 2Hi, 4HI PT, and 4LO PT. The 4WD modes are not for use on high-traction surfaces such as dry roads. The NP208 was used through at least 1987.

More commonly, Command-Trac is used to refer to the NP/NV-231 or NP-207 transfer cases introduced along with the Jeep Cherokee (XJ) in 1984. The system offers a chain-driven, aluminum, "shift-on-the-fly" transfer case. The "shift-on-the-fly" feature provides manual ease and assist while engaging 4WD. Command-Trac should only be driven in 4WD on low-traction surfaces due to the front and rear axles being locked together (no differential action in the transfer case). Driving in 4WD on dry pavement causes excessive tire and drivetrain wear. Four-wheel modes are most commonly used for wet/slick surfaces or extreme weather conditions (rain, snow, etc.) (4H), towing (N), and off-road activities (4L).

There are reports of a modified version known as NP-231J HD which was supposedly (SP) a "heavy duty" version for the Jeep Grand Cherokee (ZJ) with V8 engines. The NP/NV-231 case is a chain-driven unit that takes 21- or 23-spline input shafts. The 23-spline was for the AX-15 transmission, and the 21-spline was used for the AX-5 and BA 10/5 transmissions. Low range for this case was 2.72 and high range was 1.00.

The Command-Trac HD transfer case was used in 6-speed Liberty KJ's from 2005 to 2007. Although sometimes referred to as the "NV(NP)231HD," the transfer cases are actually the 241 series used in full-sized trucks from other makers (241D or 241C). The Jeep version is labelled "NV(NP)241J." This is not the NV241OR transfer case found in the Jeep Wrangler Rubicon, which uses a 4.0 low range and has a reinforced case. Dodge uses a 241DHD, which has a reinforced case but the 2.72 low range.

The Jeep Grand Cherokee/Commander line no longer offers a part-time transfer case option. The reason behind this was its poor sales along with an improved Selec-Trac. Selec-Trac and a simplistic Quadra-Trac had the convenience and comfort of "Full-Time" all wheel drive that Command-Trac lacked for "luxury" SUV's that did not require the more rugged part-time system.

The terms "Command-Trac" and "Selec-Trac" were used in other Jeep lines and refer to different transfer cases in those lines.

Applications: 1984-2001 Jeep Cherokee (XJ) 1986-1992 Jeep Comanche (MJ) 1987–Present Jeep Wrangler (YJ, TJ, JK, JL) 1993-1995 Jeep Grand Cherokee (ZJ) 2002-2007 Jeep Liberty/Cherokee (KJ) 1980-1987 Jeep Cherokee/Wagoneer/Grand Wagoneer (SJ)

Command-Trac II Command-Trac II works the same as Command-Trac but uses a console mounted switch to control the MP1522 transfer case as opposed to a floor mounted lever.

Applications: 2008-2012 Jeep Liberty/Cherokee (KK)

Rock-Trac Rock-Trac is similar to Command-Trac but uses the New Venture Gear NV241OR and adds locking differentials and 4:1 low gear ratio. In 2007 an electric front sway bar disconnect was added and the locking differentials switched from air-actuation to electric actuation.

Applications: 2003–Present Jeep Wrangler Rubicon (TJ, JK, JL) 2005–Present Jeep Wrangler Unlimited Rubicon (TJ, JK, JL) 2020–Present Jeep Gladiator Rubicon (JT)

Selec-Trac

Selec-Trac Selec-Trac was first introduced in the full-size Jeeps (SJ) in 1983 using the New Process NP228 and NP229 transfer cases. These are very similar to the Quadra-Trac NP219 transfer case described in the next section below. The differences are 1) they added a 2WD mode for fuel savings and 2) the 2WD-to-4WD modes were controlled via a vacuum switch on the dashboard. The Hi-N-Lo range selection was still performed using a shift lever on the console. The NP228 differs from the NP229 by not having the viscous coupling in 4WD Hi mode, reverting to a simpler open center differential. Both transfer cases still lock the center differential in 4WD Lo mode. The NP228/229 transfer cases were available in the full-size Jeeps from 1983 to 1991. The NP228 was also available in the XJ Cherokee and Wagoneers and the MJ Comanche pickups from 1984 until replaced by the NP242 in 1987. Several companies have offered a dual shift lever conversion which replaces the vacuum switch and solenoid with a more reliable second console lever for 2WD-4WD mode selection.

The AMC Eagle used the NP119 transfer case in 1980, a strictly full-time all wheel drive model. From 1981 to 1988, a similar system was employed, dubbed "Select-Drive", which allowed the vehicle to switch from all wheel drive to 2WD using the NP129 model transfer case. The NP129 contained a viscous coupling around an open differential for added traction in slippery conditions. The NP128 has also been found equipped in select model years, which does not feature a viscous coupling.

The NP242 Selec-Trac transfer case debuted alongside the Fuel-Injected 4.0L Inline-6 in the compact Jeep Cherokee in 1987. The shifter has modes 2WD - 4WD Hi Part-Time - 4WD Hi Full-Time - N - 4WD Low. There is a center differential that is open in 4WD Hi Full-Time mode and distributes torque 48/52% front-to-rear. This mode can be used on dry pavement or slippery surfaces with only a small fuel mileage penalty compared to 2WD mode. In 4WD Hi Part-Time and 4WD Low, the center differential is mechanically locked, so these modes are for slippery surfaces only. Low range engages a 2.72:1 planetary gear ratio for increased torque and low speeds. Overall, this system functions very much like the NP228 transfer case above, just with all of the mode and range controls via a single, console-mounted shift lever. It was available in the 1987 to 2001 XJ Cherokee and Wagoneer, the 1987 to 1992 MJ Comanche, the 1993 to 2004 ZJ and WJ Grand Cherokees, the 2002 to 2007 KJ Liberty, and the 1998 to 2000 Dodge Durango. It was replaced in the 2005 Grand Cherokee by the Quadra-Trac II system featuring the NV245 transfer case with 4WD Auto mode and in the 2008 KK Liberty by Selec-Trac II using the MP3022 transfer case.

Applications: 1983–1991 Jeep Wagoneer/Grand Wagoneer and Jeep full-size pickups (SJ) 1984–2001 Jeep Cherokee/Wagoneer (XJ) 1986–1992 Jeep Comanche (MJ) *note, 1986 models were available with Selec-Trac utilizing only the NP228/NP229 1993–2004 Jeep Grand Cherokee (ZJ, WJ) 1998–2000 Dodge Durango 2002–2007 Jeep Liberty/Cherokee (KJ)

Selec-Trac II Selec-Trac II uses a console mounted switch to control the MP3022 transfer case. The switch controls the 4WD mode with options of 2WD - 4WD Auto - N - 4WD Low. The MP3022 transfer case uses an electronically controlled clutch pack to bias torque from 100% rear to 50/50% front/rear. The transfer case has no center differential, so power can only be supplied to the front axle when the rear wheels begin to slip. In this way, the transfer case works almost identically to the NV247 transfer case used in the Quadra-Trac II system in 1999 to 2004 WJ Jeep Grand Cherokees. In 4WD Low mode, the clutch pack is locked and power flows through a 2.72:1 planetary gear set for higher torque at lower speeds.

The 2018 and newer JL Wrangler comes by default with Command-Trac, but its Sahara trim can be upgraded to Selec-Trac II, marketed as simply Selec-Trac, utilizing the MP3022 transfer case.

Applications: 2008–2012 Jeep Liberty/Cherokee (KK) 2018–Present Jeep Wrangler Sahara (JL) 2021–Present Jeep Gladiator (JT)

Quadra-Trac

The Quadra-Trac name is used on a variety of full-time 4WD systems. The first version used the Borg-Warner BW1339 transfer case and was produced from 1973 to 1979. The next version used the New Process NP219 transfer case and was produced from 1980 to 1982. From 1993 to 1995 the New Process NP249 transfer case carried the name. And from 1996 to 1998 the transfer case was manufactured by New Venture Gear with some minor improvements and it was renamed the NV249.

Quadra-Trac was the trade name for the Borg-Warner 1305 and 1339 gear cases. It was a chain-drive system introduced in 1973 on the full-sized Jeep line behind the AMC version of the Turbo-Hydramatic 400 automatic transmission. CJ7s also received the Quadra-Trac starting in 1976. The BW1305 included 1) a differential with a cone-type slip-limiting clutch to distribute torque between the front and rear output shafts and 2) a vacuum-switch-operated differential lock. It offered only 4WD Hi modes in full-time (open) or part-time (locked) modes. The BW1339 added a 2.57:1 low range gearset to the BW1305, enabling 5 modes: 4WD Hi Locked, 4WD Hi Open, Neutral, 4WD Low Open, and 4WD Low Locked.

The Jeep Quadra-Trac was differentiated from the open "New Process" Gear NP203 used by Dodge, General Motors, and Ford in that it included a center limited slip differential feature, in this case a clutch pack.

Applications: 1973-1979 Jeep Wagoneer (SJ) 1973-1979 Jeep Cherokee (SJ) 1973-1979 Jeep Gladiator 1976-1979 Jeep CJ-7

The Borg-Warner system was replaced with a "New Process Gear" NP219-based system in 1980John, Full-size Jeep pages on wagoneers.com 25 February 2002 . Retrieved on 9 October 2010. The NP219 Quadra-Trac transfer case was available in full-size Jeep Cherokee, Wagoneer, and Grand Wagoneer from 1980 through 1982. It offered the following modes: 4H LK, 4H, N, and 4L. In 4H (full-time 4WD High) a center differential with a viscous limited-slip coupling is used between the front and rear output shafts. A 2.61:1 low range was engaged in 4WD Lo mode. And in both '4H LK' (4WD Hi Locked) and '4L' modes the center differential is mechanically locked. The 'N' mode disengages the transfer case, transmission, and engine from the axles, thus enabling flat-towing the Jeep behind another vehicle. In 1983, the NP219-based Quadra-Trac system was replaced by the NP228/229-based Selec-Trac, adding a fuel-saving 2WD mode to the full- and part-time 4WD modes of Quadra-Trac.

Applications: 1980-1982 Jeep Wagoneer and full-size pickups (SJ)