Editing Swapping out a TH350 for a TH700R4

Swapping out a T-350 transmission for a 700R4. ==Tips== This swap to the 700R4/4L60/4L60E transmission requires several changes. *The overdrive transmission is longer than a T-350 that has a 6 inch tail housing. A T-350 with a 9 inch tail housing is similar in length to the TH700R4. *The 4x4 output shaft of the 700R4 is longer and requires a shaft change to a custom shaft from Advance Adapters. *Crossmembers must be moved (usually for RWD applications; some vehicles e.g. 1973-'87 Chevrolet/GMC C/K (also 1987-'91 R/V series e.g. K5 Blazer, Jimmy, Suburban, crew/chassis cab) with 4 wheel drive can retain the stock crossmember location (transmission adapter to transfer case must match the transfer case bolt pattern; 700R4 made optional 1982-'91; Advance Adapters does manufacture a transmission adapter if converting the THM400 to a 700R4/early 4L60E when mated to the stock THM400 transmission adapter which also includes a 32 splined output shaft (or swap out the input gear on the transfer case with one having 27 splines). *Drive shaft lengths (4x4) may need changed depending on the truck configuration (if using non-stock transfer cases e.g. NP205 in place of an NP241 and/or driveline swaps e.g. Jeep 4.0L to 700R4 and/or Chevrolet powertrain to existing transfer case (Jeep, Land Cruiser) - 700R4 transmission adapter to transfer case has a THM350 bolt pattern but thinner to compensate for the 700R4 and early 4L60E prior to the introduction of the 2-piece case/bolt on bell housing (1996+ 4L60E has a 2-piece bell housing and a six bolt tail housing). *You need to hook up the wiring to the 700R4 transmission to have converter lockup control. There are several kits available from simple to road speed adjustable designs, or the wiring can be done from scratch. *4L60E (1993-present) has full electronic shifting done by the PCM - early model looks similar to 700R4 but without the mechanical governor assembly and the presence of a connector plug (green, or black if after 2004). Some early 4L60E will have a pulse width modulator (PWM) and VSS output sensor on the RH side during the 1995 model year when OBD 1.5 was phased in (e.g. California-market automobiles); 1996-2002 4L60E (all PWM equipped) introduced a bolt on bell housing and six bolt tail housing (first used with the 4.3L V6-90 and some GMT400s (C/K truck, SUVs (Tahoe, Yukon, Suburban, Escalade, Denali); 1997-present LSx (GEN III, IV) has a seven bolt bell housing and a longer input shaft using torque converters with a smooth faced snout which is 5/8" longer than the 4.3L/GEN I which requires the use of a transmission adapter 19154766 (exception for Supermatic torque converters sold through Chevrolet Performance). 4.3L V6-90 engines used with GMT800, including Astro/Safari, GMT330 (Blazer, Jimmy, Bravada, S10/Sonoma) had redesigned crankshaft pilot depth of 1.410". [[Category:GM]]

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