Toll Free: 1-800-622-4836

Transmission Identification GM

This page is designed to assist you in identifying the transmission installed in your vehicle. We are making the assumption that your vehicle has the original type transmission that was installed at the factory. In most cases, if your vehicle has been converted from an overdrive to a 3-speed, you can still use this guide for identification. If the drivetrain in your vehicle has been customized in any other way, you should call our techs for help identifying your transmission.


Front Wheel Drive

3 Speed

Year Model
1980-1981 125 Square side oil pan, “Metric” printed on 16 bolt pan. Lock-Up identified by electrical connector. Pictures
1982-up 125 Lock-Up (3T40)
1979-1981 325 (Eldorado,
Toronado, Riviera)
Left hand drive, bolt-on governor cover, 3″ deep rear oil pan, 15 bolt pan. Pictures

Overdrive

Year Model
1982-1986 325 4L (Eldorado, Toronado, Riviera) Left hand drive, no modulator, large 6″ hump on rear oil pan.
1985-1991 440 (4T60) Vacuum modulator, T.V. cable, large side oil pan that goes around axle shaft, one piece tail w/ speedo housing. (Read More…) Pictures
1991-up 440E (4T60E) Vacuum modulator, no T.V. cable, bolt-on extension housing with electronic speedo hole. (Read More…) Pictures
1997-up (supercharged) 4T65E Bolt on ext housing, No vaccume mod, Smooth reverse servo cover, Aluminium side cover with 6 bolt holes (Read More…) Pictures
1993-up 4T80E ’93 and up 4.6 Cadillac (and Olds. Aurora 4.0), Much larger than 4T60E or 4T65E, Bolt on ext housing, Case connector hangs off case on a harness (Read More…) Pictures

Rear Wheel Drive

3 Speed

Year Model
1976-1979 200 No modulator, 11 bolt pan, no 4X4′s, normally has “Metric” on the pan. Lock-Up has electrical connector on driver’s side of case above and behind the gearshift linkage. Pictures
1980-up 200 Lock-Up
1980-1984 250 Lock-Up
(Cars only)
Looks identical to the 350. Look for band adjustment nut and stud 3″ behind the cooler line fittings. May have a ribbed pan. Pictures
1969-1979 350 Modulator on right rear pointing to rear, has square pan with right rear corner cut off. Lock-Up has wire plug-in on left or driver’s side.
1980-1986 350 Lock-Up
1964-up 400 (3L80) (375) Modulator on right or passenger front pointing to the side, 13 bolt pan.

Overdrive

Year Model
1981-1990 200 4R (Cars) Non removable extension housing, no modulator, double dip in oil pan, 16 bolt pan. Cadillac only may have 6 hole, heavy duty aluminum dust cover. Pictures
1982-1993 700 (4L60) Removable extension housing, no modulator, rectangular 16 bolt pan, T.V. cable, Lock-Up connector on left side. (Read More…) Pictures
1993-up 700E (4L60E)
*READ NOTICE*
Removable extension housing, large round electrical connector on right side, 16 bolt pan, no T.V. Cable. (Read More…) Pictures
1991-up 4L80E (Trucks only) Removable tail, 17 bolt oil pan comes to a point in the rear, large round electrical connector on left side. Pictures