Torque converter 977 Tacoma 4wd automatic transmission - when selecting gear (reverse,drive, lo, etc.,) the vehicle will not move. I can get it to intermittently limp along, but when trying to dive it, it will act as if the transmission or something in the drive train disengages and the vehicle will not move. There are no clunking sensations or other noises associated with it, just doesn't go. Torque converter?

run the fault codes
indicates a problem in the torque converter clutch servo/solenoid

is there any oil in the transmission
unless you have a dipstick ( GMC products are normally sealed ) it is very possible that there is no oil in the transmission
the transmission oil pump is part of the transmission around an input shaft and requires the transmission removal for repair / replacement
take it to an accredited transmission service center and have it tested and properly diagnosed

Both error codes you have are transmission related. P0736 is an error for reverse has wrong gear ratio. P0700 is a general transmission problem code
http://www.obd-codes.com/p0700
http://www.obd-codes.com/p0736
for more information.

The problem is that by driving in 4wd on hard surface you experience what is known as torque wind up in the transmission, transfer case and drive lines. This loads up the gears so an actuator cannot move a selection until the torque wind up is reduced (reverse or shunt back)
IT is not a problem if you are on slippery roads , gravel, grass or any surface where the tyres can slip and relieve the wind up
If you persist in the practice of driving in 4wd on hard surfaces then be prepared for transfer case , drive line problems well before expected wear time.

The question is a little vague but I think I know what your referring to. All modern automatic transmissions have torque converters. This is the device that connects the engine to the transmission. All vehicle manufacturers like the trans to be nice and smooth shifting. That's great but it does come with some minor drawbacks. If you are facing slightly down hill and you put your car in reverse but do not step on the gas slightly I can guarantee that you will indeed roll forward. You can eliminate that issue by holding your left foot on the brake while you shift into reverse. Then, as soon as you feel the trans engage, gently depress the gas pedal with your right foot and it will eliminate that forward roll problem.

Im assuming you mean that the vehicle wont move when put it in gear and its an automatic! Check the transmission fluid level if it is ok check if vehicle will move in any other gear reverse 1 or L etc. If not it maybe a torque converter issue and maybe best for a transmission shop to sort

Chances are is that the torque converter needs to be replaced. However, the transmssion on this vehicle are only serviceable by transmision shops. No regular mechanic will open up the transmission. When the torque converter fails (clutch and plates shutters to small pieces) the debri flows in the transmision thereby potentially destroying the gears and/or clogging the filter and pump. Go straight to a reputable transmission shop and let them correctly diagnose the transmission.

Every automatic transmission has a converter (except really early 50's chrysler clutch flites)
And yours does have lockup feature (fourth gear)
Likely it has failed.

Transmission Description The E4OD transmission is a fully automatic, electronically controlled, four-speed unit with a torque converter clutch. The main operating components of the E4OD transmission include a torque converter clutch, six multiple-disc friction clutches, one band, one sprag one-way clutch and two roller one-way clutches that provide for the desired function of three planetary gear sets. Transmission gear selection in the (D) range and converter clutch operation is controlled by the powertrain control module (PCM) (12A650). Operating conditions are relayed to powertrain control module by various sensors throughout the vehicle. The powertrain control module compares these conditions with electronically stored parameters and logically determines how the transmission should operate. A torque converter (7902) couples the engine to the transmission gearset via the input shaft (7017) and the torque converter impeller hub. The impeller hub provides engine rpm to the positive displacement pump. The flow from the pump is proportional to engine rpm, and excess pump capacity is exhausted back to the pump inlet. The input shaft transfers power into the transmission gearset. The power input is controlled by the application of the torque converter clutch, which is scheduled through the powertrain control module. The application of the piston plate effectively replaces the hydraulic coupling between the converter cover and the turbine with a mechanical coupling between the converter cover and the turbine hub. This mechanical coupling helps improve fuel economy and wide-open throttle performance by eliminating converter slip. Transmission shift selection and torque converter clutch operation are controlled by the PCM. They are calibrated to provide the optimal transmission state. This state is commanded to the transmission solenoid body. In the (D) range, automatic operation of all four gears is possible. The transmission control switch, located on the vehicle's shift lever disables overdrive operation and enables automatic operation through the first three gears. Whenever the ignition switch is turned on, the vehicle will automatically provide overdrive operation regardless of the switch position the last time the vehicle was running. Manual gear selection is available in the 1 and 2 range. Second gear is commanded when the gearshift selector lever is in the 2 range and when downshifted into the 1 range at speeds above approximately 56 km/h (35 mph) (for diesel 48 km/h [30 mph]). First gear is commanded in the 1 range at start-ups and when downshifted into 1 range below approximately 56 km/h (35 mph) (for diesel 48 km/h [30 mph]). Any reference to intermediate brake drum or direct clutch cylinder are one and the same.
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I think this is your problem:

Programmable Speedometer/Odometer Module (PSOM): Description: The programmable speedometer/odometer module receives input from the rear brake anti-lock sensor, which is mounted on the rear axle differential housing. The PSOM processes this input signal information and relays it to the powertrain control module and the speed control module. This signal tells the powertrain control module the vehicle speed in miles per hour (mph). Used as an input in determining shift scheduling and electronic pressure control. Symptoms: Harsh engagements, firm shift feel, abnormal shift schedule, unexpected downshifts may occur at closed throttle, abnormal torque converter clutch operation or engages only at wide-open throttle (WOT). May flash transmission control indicator lamp. Diagnostic Trouble Codes: 452, P0500, P1500, P1501, P0503

Check you transmission fluid if its thin theres your issue if not it could be your bands or your torque converter.