Domestic truck trans ID guide

T170 Series

T170F-RUG 'SMOD'

Side Mounted Overdrive. Found in 1978-79 Ford F100-F250 light duty pickups and 1978-1987 E100-E150 vans. Synchronized in all forward gears, with top loaded cast iron case. This is a variant of the classic Ford Toploader but with an overdrive 4th gear. Traditional external linkage shifter mounted to left side. This unit was produced for cars also but with lighter duty bearings and gear train.

T170FS-RUG 'SROD'

Single Rail Overdrive. Found in 1980-83 Ford F100-F250 light duty pickup trucks. Has an aluminum case with sheetmetal top cover. Shifter turret mounted on left side of extension housing with tube connecting to main case; single shift rail inside tube. 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-RTS 'TOD'

Topshift Overdrive; RTS = remote tower shift. Found in 1984-87 Ford F100-250 light duty trucks. Top loaded 4 speed with 4th being overdrive. Aluminum case & top cover with integral shift tower similar to NP435.

4-speed transmission found in 1964-80 Chrysler passenger cars, 1976-90 Dodge trucks, and 1981-87 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".

Top loaded heavy-duty 4-speed transmission found in 1962-91 Dodge trucks, 1965-87 Ford trucks, some 1968-72 GM HD 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.

aka CH465. Top loaded heavy-duty 4-speed transmission found in many 1968-91 GM trucks.  Cast iron case, extension housing and lid with integral shift tower (1988-91 lid is aluminum and change to hydraulic clutch around 1986). 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.

Top loaded heavy-duty 4-speed transmission found in 1948-64 Ford trucks and 1955-72 Jeep. Cast iron case and shift cover. The hand of the helical gear cut was changed in 1955, thereafter referred to as T98A. Easily confused with later BW T18. The T98 has a 43 tooth first-reverse sliding gear (the rearmost mainshaft gear, spur cut) and a 17 tooth cluster gear (also spur cut).

Successor of the T98. Top loaded heavy-duty 4-speed transmission found in 1965-87 Ford trucks, 1972-79 Jeep, and 1965-73 International. Cast iron case and shift cover. Case casting number is 1301. One PTO port on passenger side. Synchronized in 2nd,3rd, and 4th, with 1st and reverse non-synchronized. Easily confused with earlier BW T98 and T98A models, particularly as lid of T18 is shared with and often marked as T98.

Top loaded heavy-duty 4-speed transmission found in 1974-87 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 and has one PTO port on each side. The T19 has a single step reverse idler gear while the T18 has a 2 step reverse idler.

5 speed found in 1984-2002 Jeep vehicles (1987+ w/ 2.5L I4 only). Fully synchronized center support type of transmission with aluminum case and extension housing. A less prevalent AX4 4 speed version was also available in 1984-1986 Cherokee.

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.

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.

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.

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 tailhousing.

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.

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.

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 yellowish white plastic housing with built-in reverse detent and bolts onto the tail extension with 4-bolt rectangular pattern.

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.

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.

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.

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 but lack of meaningful ID tag makes this difficult.

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).

5 speed, fully synchronized top loaded heavy-duty transmission for GVWR exceeding ~8500 lb. Found in 1992-2007 GM full size HD trucks and 1992-2005 Dodge trucks. Cast iron case and extension housing with aluminum shift cover.

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.

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.

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.

Heavy duty 5 speed fully synchronized transmission with aluminum case and extension housing. The S5-42 is found in 1988-94 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.

Heavy-duty 6 speed found in 1999-2010 Ford SuperDuty trucks (1999-2003 w/ 7.3L diesel & 2002-2010 w/ gas engine only) + 2001-2006 GM HD trucks w/ 6.6L diesel or 8.1L gas (6.0L = NV4500). Reverse upper left. Ford knob shift pattern shows "L" then 1-4 and "OD" while GM shows typical 1-6 pattern. Ford shifter base has a 6-bolt pattern while GM has a simpler 4-bolt pattern (oddly shared w/ Ford's heavier S6-750). All gears are synchronized. This unit has an aluminum case with integral bell housing, a center support, and rear case. ID tags are mounted on the left side of the main case.

Heavy-duty 6 speed closely related to the S6-650. Found only in 2003-2010 Ford SuperDuty trucks w/ 6.0L or 6.4L diesel. Reverse upper left. Shifter base has a 4-bolt pattern shared w/ GM S6-650 but different stub depth. All gears are synchronized. This unit has an aluminum case with integral bell housing, a center support, and rear case. ID tags are mounted on the left side of the main case.

Heavy-duty 6 speed found in 1998-2005 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.

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.

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.

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.