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Domestic truck trans ID guide

Four Speed Transmissions

T170 Series

T170F (Code-RUG)

Side mounted Overdrive (SMOD). Found in 1978-84 Ford light duty pickups and vans. Synchronized in all forward gears, with top loaded cast iron case. Similar in appearance to the Ford "top loader trans" but has overdrive 4th gear. Three shift rails mounted to the left side of case. This unit was produced for cars also but with lighter duty bearings and gear train.

T170FS (Code-RUG)

Single Rail Overdrive (SROD). Found in 1980-83 Ford light duty pickup trucks. Has an aluminum case with shifter turret mounted on extension housing. Synchronized in all forward speeds with 4th being overdrive. There is also a passenger car version of this unit with lighter duty bearings and gear ratios.

T170FT (Code-RTS)

Top shift overdrive (TOD). Found in 1984-85 Ford F100-250 light duty trucks. Top loaded 4 speed with 4th being overdrive. Aluminum case and shift tower.

N-T170FS
New Process A833

4-speed transmission found in 1964-80 Chrysler passenger cars, 1976-85 Dodge trucks, and 1981-89 GM trucks (RPO MY6). All forward speeds synchronized. Manufactured in both direct drive and overdrive models. 10-bolt shift cover mounted on left side of transmission case. Early models had iron cases; later model cases are aluminum. Case length measures 10 5/8".

N-NP A833
New Process 435

Top loaded heavy-duty 4-speed transmission found in 1962-91 Dodge trucks, 1965-87 Ford trucks, some 1968-72 GM trucks, and 1964-85 International trucks. Cast iron case and extension housing but aluminum top cover with integral shift tower. 2nd through 4th gears are synchronized; 1st and reverse use non synchronized sliding gear.

N-NP435
Muncie SM465
(shown without extension housing)

Top loaded heavy-duty 4-speed transmission found in 1968-91 GM trucks but overlapping with NP435 and A833 (light duty).  Cast iron case, extension housing and shift tower. Synchronized in 2nd, 3rd, and 4th. Cases have PTO openings on both sides. 1st and reverse gear are non-synchronized. 1st gear is a deep reduction low gear and shift knob may show H pattern with Low, 2,3,4.

N-MUNCIE SM465
Borg Warner T18
(shown without extension housing)

Top loaded heavy-duty 4-speed transmission found in 1965-93 Ford trucks, 1972-79 Jeep, and 1965-73 International. Cast iron case and shift cover. Case casting number is 1301. Synchronized in 2nd,3rd, and 4th, with 1st and reverse non-synchronized. Easily confused with earlier BW T98 and T98A models. Care should be used when ordering parts to make positive ID of unit.

N-BW T18
Borg Warner T19
(shown without extension housing)

Top loaded heavy-duty 4-speed transmission found in 1968-87 Ford trucks and 1974-85 International trucks. Cast iron case and shift cover. Case casting number is 1309. Easily confused with T18, but the T19 is synchronized in all forward speeds. The T19 has a single step reverse idler gear while the T18 has a 2 step reverse idler.

N-BW-T19
Five Speed Transmissions
Aisin Warner AX5

5 speed found in 1984-2002 Jeep vehicles with 2.5L I-4 (gas) + 1984-87 with diesel. Fully synchronized center support type of transmission with aluminum case and extension housing.

N-AX5
Aisin Warner AX15

5 Speed found in 1989-99 Jeep vehicles with 4.0L I-6 and 1992-99 Dodge Dakota trucks (except V8). Fully synchronized center support transmission with aluminum case and extension housing. Similar in appearance to AX5 but larger with heavier duty gear train.

N-AX15
Borg Warner / Tremec T5

All-aluminum 5 speed top loading transmission found in 1982-87 AMC & Jeep , 1982-95 GM S10 trucks, 1985-92 Astro van + 1983-2002 Camaro, 1984-86 Chevette, and 1983-2010 Mustang (except 1996+ V8). All forward gears synchronized. Early design has brass synchronizer rings while later "world class design" uses paper lined rings and tapered bearings on countershaft. Model number located on ID tag attached to extension housing bolt starts with 1352.

N-T5
Peugeot BA10 (AX18)

Light duty aluminum 5-speed transmission found in 1987-mid 89 Jeep vehicles with 4.0L I-6. "Suitcase" design where the main case splits apart lengthwise. Note location of shifter and how it retained as there are two designs. Additionally there is 5 or 6 bolt mounting flanges for the transfer case on 4wd models.

N-PEUGOT BA10
New Process 535 (aka New Venture 2500 or NP A535)

Light duty 5 speed found in 1987-1992 Dodge trucks. Fully synchronized center support aluminum case with 4 bolt top cover. The shifter is located behind top cover on top of transmission.

N-NP2500,NV535
FM145

5-speed transmission manufactured by Mitsubishi, found in 1985-87 Ford Ranger & Bronco II with V6 or diesel (no 4 cyl - they are TK4 or TK5). Only produced for 4wd but used in 2wd Bronco with an open dummy transfer case.  Bell housing, case and extension housing are aluminum with removable bell housing. The extension housing measures 10" in length. There is a 12-bolt stamped steel bottom pan on unit - opposed to the finned aluminum pan on Toyo-Kogyo (Mazda) units for 4 cyl. On left side of case is a red ID tag giving Ford part number and unit serial number. Shifter base has a black plastic housing with a 4-bolt trapezoidal pattern.

N-FM145
FM132 / FM146

5-speed transmission manufactured by Mitsubishi, found in 1988-92 Ford Ranger & Bronco II - 2.9L V6 only (all others were M5OD). 2wd model is called FM132, 4wd model is called FM146 (shown). Aluminum bell housing, case and extension housing with removable bell housing. The extension housing measures 13" in length. 12-bolt stamped steel oil pan - opposed to the 14-bolt finned aluminum pan on Toyo-Kogyo units for 4 cyl. A red ID tag located on left side of case shows Ford part number and unit serial number. Shifter has a flange that bolts onto a tower rising from a small top cover that is aluminum.

N-FM146
Toyo-Kogyo TK-4 & TK-5

4 & 5-speed transmissions manufactured by Mazda, found in 1983-87 Ford Ranger & Bronco II vehicles - 4 cyl gas engines only. Top-shift, four-part aluminum case. 14-bolt finned aluminum oil pan - opposed to the 12-bolt stamped steel pan on Mitsubishi FM units for V6 & diesel. A red ID tag located on upper right side of case shows Ford part number and unit serial number. Shifter has a yellow/white plastic housing with built-in reverse detent and bolts onto the tail extension with 4-bolt rectangular pattern.

N-TK5
D50

D50 is a common industry name describing a series of Mitsubishi manufactured 4 and 5 speed transmissions, which are found in Dodge and Mitsubishi small trucks. The models include the KM131 4 speed transmission used in 1983-85 Dodge D50 trucks, the KM132 5speed, 2wd transmission used in 1983-1996 Dodge D50 trucks, and the KM145 5 speed, 4wd transmission used in 1983-1996 Dodge D50 trucks. Also found in Mitsubishi trucks of the same era. Similar in design to the FM146 except bell housing is integral to the main case. There are many design levels of this unit and it is extremely important to get tooth counts and input bearing numbers before ordering parts. There should be a model number and alphanumeric code stamped on the bell housing which helps to identify the units.

N-D50
NV1500

5 speed fully synchronized transmission, with bell housing integral to aluminum transmission case. Found in 1996-2003 GM S10 w/ 2.2L I-4, 1999-2002 Dodge Dakota w/ 4 cyl, and 2002-2004 Jeep w/ 2.4L I-4. Wrangler models were called NV2550 but appear identical to NV1500. Similar to NV3500 but slightly smaller.

N-NV1500
Getrag 290, MG290, HM290, 5LM60

5 speed fully synchronized "light duty" transmission with aluminum case and integral bellhousing for GVWR below ~8500 lb. Found in 1988-1992 full size GM trucks & 1990-1992 S10 trucks w/ 4.3L V6 only. Based on the Getrag 290, but revised multiple times. It began in 1988 as the HM290 found in GM trucks, later re-designated 5LM60 with early and late designs - all of these models have 4 shift rails. In 1993 the unit was redesigned with a single shift rail and named NV3500 (see below). Due to the variations across make, model, and year, it is critical to positively identify exact trans model to get the right parts.

N-NV3500
NV3500

5 speed fully synchronized "light duty" transmission with aluminum case and integral bellhousing for GVWR below ~8500 lb. Found in 1993-2007 full size GM trucks, 1993-2005 S10 trucks w/ 4.3L V6 only, 1994-2004 Dodge Ram, and 1994-2004 Dakota V8 (+ 1999-2004 V6). Evolution of the Getrag 290 (above); redesigned with a single shift rail but similar exterior making it hard to differentiate. Due to the variations across make, model, and year, it is critical to positively identify exact trans model to get the right parts.

N-NV3500
NV3550

A light duty fully synchronized 5-speed transmission closely related to NV3500. Found in 2000-04 Jeep vehicles with 4.0L I-6. The case and extension housing are aluminum with a removable bell housing (vs NV3500 integral bellhousing).

N-NV3550
NV4500

5 speed, fully synchronized top loaded heavy-duty transmission for GVWR exceeding ~8500 lb. Found in 1992-2007 GM full size HD trucks and 1994-2005 Dodge V8 trucks. There is also a 4500HD model found in 1994-2004 Dodge trucks with V10 & diesel engines. Cast iron case and extension housing with aluminum shift cover.

N-NV4500
Getrag G360

Heavy-duty 5 speed fully synchronized transmission with cast iron case and aluminum shift cover. Found in 1989-93 Dodge trucks with Cummins diesel engine. Due to design limitations and cost of parts, a swap to NV4500 is recommended when repair is needed.

M5R1

Mazda-built, fully synchronized 5-speed transmission, found in 1988-2011 Ford Ranger and Explorer trucks - all engines except 2.9L. Aluminum case with integral bell housing, aluminum extension housing, and aluminum shift cover.  ID decal on left side of case. The shift cover was modified in 1995 to have a taller shift cover and neutral position switch in cover was eliminated. In 1998 the stub stick in shift cover was changed to accept shift lever with groove on right side. Ratios and starter location vary with engine size.

N-M5R1
M5R2

Mazda-built 5 speed fully synchronized transmission found in 1988-2008 Ford F150 series trucks and full size Broncos. Aluminum case, extension housing, and shift cover, with integral bell housing. Very similar in design to M5R1, but larger with shift lever located in center of shift cover. 1995 and later models have top cover reverse light switch moved to forward corner of shift cover. In 1996 case is changed to accommodate modular motor (4.6L), with starter bolt pattern being triangular. In 1999 the case was changed for 4.2L 4wd drive vehicles. The case is very similar to earlier style units with case length shorter on 4.6L and 4.2L models.

n-M5R2
ZF S5-42 and S5-47

Heavy duty 5 speed fully synchronized transmission with aluminum case and extension housing. The S5-42 is found in 1987-94 Ford F250, F350, F450, and F-SuperDuty trucks. The S5-47 covers 1995-2001. Both units have PTO covers on each side of case. The bell housing is integral to the case. Shifter is mounted to small shift cover on top of unit. The F-SuperDuty model has a mechanical park brake assembly mounted to the extension housing. On the left side of the case is mounted and ID tag, which gives the Ford Part number, the ZF part number and the unit serial number. Great care should be taken to properly identify the unit as both the S5-42 and S5-47 appear similar and with the great variety of ratios available, it is easy to order the wrong parts.

N-ZF S542,S547
Six Speed Transmissions
ZF S6-650

Heavy-duty 6 speed found in 1998-2010 Ford SuperDuty trucks + 2001-2007 GM HD trucks (except 6.0L gas = NV4500). Reverse upper left. Ford knobs show "L" then 1-4 and "OD" instead of 1-6 like GM. Ford shifter base has a 6-bolt pattern while GM has a simpler 4-bolt pattern. All gears are synchronized. This unit has an aluminum case with integral bell housing, a center support, and rear case. A unique feature of this unit is an internal oil pump driven off the front of the countershaft that circulates the lube to a trans cooler. An easy way to identify this unit is by the cooling lines mounted to the case as found in automatic transmissions. ID tags are mounted on the left side of the main case.

N-ZF S650
NV5600

Heavy-duty 6 speed found in 1999-2005 Dodge Ram HD trucks with HO Cummins diesel. Overlapped with G56 in 2005 but easily distinguished by shift pattern with reverse upper right. 5.63 1st gear. All forward speeds fully synchronized, this unit has an aluminum bell housing, cast iron case and extension housing, with top mounted shifter.

N-NV5600
NSG370

Light duty 6 speed found in 2005-2008 Jeep Liberty, 2005 to present Jeep Wrangler, 2004-2006 Chrysler Crossfire, 2006-2008 Dodge Nitro. Reverse lower right. This transmission utilizes bronze synchronizer collars resulting in sensitivity to lubricant make-up. Only a fluid characterized by Chrysler specification MS-9224 (e.g. Pennzoil Synchromesh) should be used in order to avoid premature wear or failure of internal parts. Shifter base is aluminum. Detents and rail controls are in the shifter base, likely to reduce manufacturing costs but resulting in a complicated and very expensive shifter base that cannot realistically be replicated by the aftermarket.

NSG370
Getrag 238

Light duty 6 speed found in 2005-2009 Dodge Dakota & Ram 1500 series trucks. Reverse lower right. All-aluminum case with provisions for mounting shifter base at rear of main case (Ram) and front of tail-housing (Dakota) - unused port has blank coverplate. Stock shifter base housing is black plastic. The Getrag 238 offers a 4.23 first gear ratio, lower than its NV3500 predecessor to improve launch feel and low-speed acceleration. The gear ratios are more closely spaced to help improve fuel economy. 6th gear 0.79 overdrive reduces downshifting. For smooth easy shifting, the transmission features triplecone synchronizers on first and second gears and double-cone synchronizers on third and fourth gears.

Getrag238
Getrag G56

Heavy duty 6 speed found in Dodge / Ram HD trucks from 2005 to present. Overlapped with NV5600 in 2005 but easily distinguished by shift pattern with reverse lower left. All-aluminum case. 6.29 1st gear. Detents and rail controls are in the shifter base, likely to reduce manufacturing costs but resulting in a complicated and very expensive shifter base that cannot realistically be replicated by the aftermarket.

G56
Based on information originally compiled by Mike Weinberg of Rockland Standard Gear for Gears Magazine, revised and updated by Core Shifters
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